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attn_map = E * W_steered * E.T</code></pre>We scale negative eigenvalues  ...
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attn_map = E * W_steered * E.T</code></pre>We scale negative eigenvalues  ...
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attn_map = E * W_steered * E.T</code></pre>We scale negative eigenvalues  ...
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<?xml version="1.0" encoding="UTF-8"?><rss xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:content="http://purl.org/rss/1.0/modules/content/" xmlns:atom="http://www.w3.org/2005/Atom" version="2.0"><channel><title><![CDATA[LessWrong]]></title><description><![CDATA[A community blog devoted to refining the art of rationality]]></description><link>https://www.lesswrong.com</link><image><url>https://res.cloudinary.com/lesswrong-2-0/image/upload/v1497915096/favicon_lncumn.ico</url><title>LessWrong</title><link>https://www.lesswrong.com</link></image><generator>RSS for Node</generator><lastBuildDate>Fri, 04 Jul 2025 13:33:35 GMT</lastBuildDate><atom:link href="https://www.lesswrong.com/feed.xml?view=rss&karmaThreshold=2" rel="self" type="application/rss+xml"/><item><title><![CDATA[The Self-Hating Attention Head: A Deep Dive in GPT-2]]></title><description><![CDATA[Published on July 4, 2025 1:07 PM GMT <blockquote>TL;DR: gpt2-small's head L1H5 directs attention to semantically similar tokens and actively suppresses self-attention. The head computes attention purely based on token identity, independent of position. This mechanism is driven by a symmetric bilinear form with negative eigenvalues, which enables suppression. We cluster tokens semantically, interpret the weights to explain the attention scores, and steer self-suppression by tuning eigenvalues.work performed as part of ARENA 5.0 Capstone project.</blockquote> Within gpt2-small lies an unusual component: attention head L1H5<a href="#fnhwjm6n1hh9q">[1]</a> which fires on semantically similar concepts. It excels at connecting related concepts: the token <code>cat</code> attends to <code>dog</code>, and <code>red</code> attends to <code>green</code> and <code>blue</code>. Normally, this would be unsurprising, as we would expect embedding vectors to already cluster based on topic/semantic categories. But oddly enough, for this head, tokens do not attend to themselves. For example, the token <code>dog</code> will attend to other animals in the context, but it will not attend to itself or other instances of the token <code>dog</code>.This behaviour is too specific to be an accident. This short research project aims to find the mechanistic explanation for this semantic grouping and self-avoidance, with the goal to develop useful techniques for analyzing attention patterns along the way.<h2>The Behaviour: Three Simple Rules</h2>Before diving into the mechanistic analysis, let's establish exactly what GPT-2 head L1H5 is doing. After analyzing its attention patterns across hundreds of sequences, the behaviour can be summarized by three rules:<ul><li>Semantic Clustering: A token attends to other tokens in the sequence that belong to the same semantic category. Examples:<ul><li><code>cat</code> attends to <code>dog</code> and <code>horse</code>, (animals)</li><li><code>red</code> attends to <code>blue</code>, <code>green</code> and <code>yellow</code>. (colours)</li><li><code>Monday</code> attends to <code>Tuesday</code> and <code>Friday</code>. (days of the week).</li></ul></li><li>Self-Suppression: A token does not attend to itself, even when it appears multiple times in the sequence.</li><li>Fallback to Beginning: If no other token in the sequence belongs to the same semantic category, the token attends to the <code><bos></code> (beginning of sequence) token.</li></ul>These rules hold remarkably consistently across different types of semantic categories, colours, months, days of the week, numbers, names, even verbs and logical operators. Broadly, the behaviour of this head as a semantic head was already mentioned in <a href="https://www.lesswrong.com/posts/xmegeW5mqiBsvoaim/we-inspected-every-head-in-gpt-2-small-using-saes-so-you-don">We Inspected Every Head In GPT-2 Small using SAEs So You Don’t Have To</a>, but there it's only described as a "Succession or pairs related behavior". <h2>Part 1: Finding What Matters</h2>First, we need to isolate this behaviour and find the components responsible for it. This required a three-step process: design a prompt to reliably trigger the behaviour, define a metric to measure it, and ablate components to see which ones break it.<h3>Setup</h3>To reliably trigger the head's behaviour, we define a simple prompt by shuffling tokens from various hand-picked semantic categories. This creates a context where L1H5 has many opportunities to demonstrate its preference for in-category attention.<pre><code><bos> blue sad cat purple purple 24 blue cat purple sheep 69 32 happy horse angry</code></pre><a href="https://mamiglia.github.io/deep-dive-L1H5/attention_pattern.html"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wxPvdBwWeaneAsWRB/hgrnh0g0ebzv6kwwfn6k" alt="Attention Map"></a>Based on the three rules observed above, we define an "expected" attention pattern for this prompt. For example, <code>purple</code> should attend to <code>blue</code>, but not to <code>cat</code> or <code>purple</code>. This gives us a target mask representing the idealized behaviour of the head.<figure class="image image_resized" style="width:47.74%"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wxPvdBwWeaneAsWRB/rnnquo7kf7boqkgkayys" alt=""><figcaption>Example of expected attention pattern.</figcaption></figure><h3>Semantic Category Score</h3>To measure how well the head's actual attention pattern, A<style>.mjx-chtml {display: inline-block; line-height: 0; text-indent: 0; text-align: left; text-transform: none; font-style: normal; font-weight: normal; font-size: 100%; font-size-adjust: none; letter-spacing: normal; word-wrap: normal; word-spacing: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0; min-height: 0; border: 0; margin: 0; padding: 1px 0}
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</style>, matches the expected pattern, M, we use a KL divergence-based score: KL({1,0}||{Pq,1−Pq}) where Pq=∑k(M⊙A)qk is the probability mass of q concentrated in M. The goal here is to measure how much of the attention probability mass is concentrated where the mask says it should be. This leads to the following loss function (credit to <a href="https://www.lesswrong.com/users/david-quarel?mention=user">@David Quarel</a> for the derivation):L=1|Q|∑q−log∑k(M⊙A)qkA lower score means a better match. As expected, a survey of all heads in the model shows that L1H5 is an outlier with a uniquely low score, confirming it's specialized for this task.<figure class="image image_resized" style="width:54.58%"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wxPvdBwWeaneAsWRB/r48jfj5rzmqv5hl3mjqc" alt=""><figcaption> </figcaption></figure><details class="detailsBlock"><summary class="detailsBlockTitle">Loss derivation</summary><div class="detailsBlockContent">We define this metric as the distance from the expected behaviour described above. We encode the expected behaviour through the mask matrix M, and define Pq=∑k(M⊙A)qk as the amount of probability mass that the attention scores places on other tokens in the same semantic category. We can then measure the distance of {Pq,1−Pq} as the KL divergence from the ideal distribution {1,0} where all the probability mass is concentrated where we expect it to be. Then this derivation followsKL(1,0||Pq,1−Pq)=1⋅ln1Pq+0⋅ln01−Pq=−lnPq=−ln(∑k(M⊙A)qk)A KL divergence between {1,0} and {Pq,1−Pq} devolves in −lnPq. This is also called Shannon Information. We then take the average across all queries q.</div></details><h3>Component Importance</h3>With a reliable metric, we can perform a mean-ablation study<a href="#fnmllnrye5z4">[2]</a>. We systematically replace the output of each preceding component with its mean value and check whether the Semantic Category Score increases; if it does it means that the component is relevant for L1H5.Surprisingly, 2 out of 4 components are completely irrelevant. The head's behaviour appears to be affected only by:<ul><li>The token embedding matrix, WE.</li><li>The first MLP layer, MLP0.</li><li>The residual stream around the first MLP.</li></ul><figure class="image image_resized" style="width:74.27%"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wxPvdBwWeaneAsWRB/s2ccsygmohpceldfjwqz" alt=""><figcaption> </figcaption></figure>Interestingly, ablating the positional embeddings (Wpos) and the previous attention layer (Attn0) had almost no effect. This is a crucial clue: L1H5 isn't using positional or sequential information to avoid attending to itself. The self-suppression mechanism must be inherent to the token representations themselves, which in turn depend only on the embedding matrix (WE) and the MLP.<img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wxPvdBwWeaneAsWRB/hrd3fzogpqpynwbfum2l" alt="">From this, we conclude that the essential input to L1H5 can be represented simply as:E=MLP0(WE)+WE∈R|V|×dThis matrix E contains a "processed" embedding for every token in the vocabulary, and it's all L1H5 needs to perform its function. <h2>Part 2: The World According to L1H5</h2>With the key inputs isolated, we now map the head's behaviour across the entire vocabulary. We will compute a full token-to-token attention matrix and use clustering algorithms to chart the head's internal 'world model'.First, since the input E is all we care about, we can circumvent the rest of the network and compute a full token-to-token attention score matrix directly:Atokens=QKT=(EWQ)(EWK)T=E,,WQWTK,,ETHere, WQK=WQWTK is the attention head's QK circuit. Visualizing this for selected semantic groups reveals the behaviour perfectly: high scores within a semantic block (e.g., colours attending to other colours) but low scores on the diagonal (a token attending to itself).<figure class="image image_resized" style="width:73.86%"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wxPvdBwWeaneAsWRB/uyy0komq9ucvsu6zexhb" alt=""><figcaption>Tokens attend to other semantically related tokens, but not themselves: Low diagonal values.</figcaption></figure>The head's semantic groupings are robust and intuitive, here we show the top 10 attended tokens for a sample of input tokens:<figure class="table"><table><thead><tr><th>Input Token</th><th>Top Attended Tokens</th></tr></thead><tbody><tr><td><code>red</code></td><td>Green, Blue, green, blue, _green, Yellow, GREEN, _blue, Green, White</td></tr><tr><td><code>69</code></td><td>72, 82, 70, 62, 71, 80, 68, 67, 66, 78</td></tr><tr><td><code>Monday</code></td><td>Wednesday, Tuesday, _Wednesday, _Tuesday, Friday, Tonight, _Friday, tonight, Tonight, tomorrow</td></tr><tr><td><code>Italy</code></td><td>Iceland, Turkish, Pakistani, Auckland, Portugal, Guatemala, Zealand, Pakistan, Mexican, Chile</td></tr></tbody></table></figure>Again note that <code>red</code> doesn't attend to <code>red</code>, nor to same meaning tokens like <code>_red</code>, <code>RED</code>, <code>_Red</code>, etc...<h3>Clustering</h3>Using this attention map, we ran the Leiden community detection algorithm<a href="#fn7lauxepfh7r">[3]</a> to cluster the main 3000 tokens of English language. The resulting clusters are surprisingly coherent and offer a fascinating glimpse into the "world model" of this specific head. You can explore this interactive map for yourself <a href="https://mamiglia.github.io/deep-dive-L1H5">here</a><a href="#fnn9zeezzzn1e">[4]</a>.<a href="https://mamiglia.github.io/deep-dive-L1H5/"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wxPvdBwWeaneAsWRB/wvfvnky6wxsjn8ssdqcp" alt="Viz"></a>If you do you may note some interesting clusters:<figure class="image image_resized" style="width:94.73%"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wxPvdBwWeaneAsWRB/pjnh6ruqbjybetm3cwku" alt=""><figcaption>Note also that tokens don't usually attend to themselves (or different versions of themselves). For example <code>east</code> doesn't attend to <code>East</code>, <code>Eastern</code>, <code>eastern</code>.</figcaption></figure> <h2>Part 3: The Mechanism of Self-Suppression</h2>To find the mechanism, we look inside the attention calculation itself. We will decompose L1H5's WQK matrix to find the mathematical property that drives both semantic grouping and self-suppression.How does a single matrix, WQK, implement this complex behaviour? Formally, for a query vector x, a similar vector y (high cosine similarity), and a dissimilar vector z, we want: xW_{QK}x^T > x W_{QK}z^T">xWQKyT>xWQKxT>xWQKzTTo empirically verify this we can plot the average attention score obtained by a pair x,y in L1H5 against their initial similarity. We can notice that the peak attention score is not at a similarity of 1, but below it, at circa 0.95, showing the head prefers tokens that are similar, but not identical.<figure class="image image_resized" style="width:86.25%"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wxPvdBwWeaneAsWRB/mbrjrpnvf9pyfylhg0fo" alt=""><figcaption>Attention score between similar tokens. Note that most of the tokens have low similarity, so most of the mass concentrated between 0.6 and 0.9. Outside of that there is less data, thus more variability.</figcaption></figure><h3>Decomposing the Matrix</h3>To understand how WQK works, we start by decomposing it into its symmetric and skew-symmetric parts:Wsym=(WQK+WTQK)/2Wskew=(WQK−WTQK)/2WQK=Wsym+WskewThis decomposition is useful because the skew-symmetric part always has zero contribution to self-attention xWskewxT=0.When we test these components separately, the result is clear. The symmetric matrix, Wsym, is able to reproduce the full behaviour on its own: high off-diagonal attention within semantic blocks and low diagonal self-attention. The skew-symmetric part has a negligible effect.<img style="width:100%" src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wxPvdBwWeaneAsWRB/yg4lttcgvrib2oe5ctt6" alt=""><details class="detailsBlock"><summary class="detailsBlockTitle">About Wskew</summary><div class="detailsBlockContent">We note that the norm of attention scores produced by Wskew is significantly lower than the Wsym, and its maximum singular value is comparatively lower than the then Wsym (1.3473 vs. 1.8611), indicating a smaller overall contribution to the final logits.While Wskew might be involved in encoding ordering or sequence information, these observations suggest that its precise role in the self-suppression mechanism is minor, prompting us to primarily focus on Wsym for further investigation.</div></details><h3>The Role of Eigenvalues</h3>So, the mystery is contained entirely within Wsym, how does it suppress self-attention? Let's start by decomposing Wsym in its eigenvalues (λi∈R) and eigenvectors (pi∈Rd), such that Wsym=PΛPT. For any symmetric matrix these values are going to be real. The attention score is then:xWsymxT=∑iλi(pTix)2If all eigenvalues λi were positive, this score would always be positive. A vector would achieve its highest score by aligning with the eigenvectors corresponding to the largest positive eigenvalues.This leads to our central hypothesis: self-suppression occurs when Wsym has negative eigenvalues. If a vector x has a significant projection onto an eigenvector pj whose eigenvalue λj is negative, that component λj(pTjx)2 will be negative, reducing the total score.<blockquote>The head suppresses self-attention for a vector x by having it align with "suppressive directions" pj in the space defined by Wsym.</blockquote><h2>Part 4: Validation by Steering</h2>To explore the proposed link between structure and function, we will perform a direct intervention by modifying the head's core matrix, attempting to 'steer' self-suppression and test the link between structure and function.Specifically, we compute the 64 eigenvalues of Wsym and find that 33 are negative, suggesting a structural basis for the behaviour. To test this, we define a steering mechanism that scales all negative eigenvalues by a factor α∈R, allowing us to elicit or remove the behaviour in a controlled way.<pre><code># Decompose the symmetric matrix
eigenvalues, eigenvectors = eigen_decomposition(W_sym)
# Scale the negative eigenvalues
for i in range(len(eigenvalues)):
if eigenvalues[i] < 0:
eigenvalues[i] *= alpha
# Reconstruct the steered matrix
W_steered = eigenvectors * diag(eigenvalues) * eigenvectors.T
# Compute new attention map
attn_map = E * W_steered * E.T</code></pre>We scale negative eigenvalues by a parameter α, reconstruct Wsym, and recompute attention.<ul><li>α<1 reduces self-suppression (self-attends more)</li><li> 1">α>1 strengthens self-suppression.</li></ul>This gives direct causal control over whether tokens attend to themselves while preserving semantic clustering. As it can be seen by the plot below, when scaling α we can successfully steer the attention map, while also maintaining the similarity of semantically related tokens.<figure class="image"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wxPvdBwWeaneAsWRB/ezywyham7ry3rzequj7i" alt=""><figcaption>Scaling of negative eigenvalues by [1.1,0,−0.5]. Note how the diagonal values become more intense as the alpha decreases. </figcaption></figure><h2>Conclusion</h2>This study offers a mechanistic account of gpt2-small attention head L1H5’s unusual behaviour. Its tendency to attend to semantically related tokens, while suppressing self-attention, appears to arise from a symmetric bilinear form with carefully placed negative eigenvalues. This effect seems to operate independently of position, relying only on transformed token embeddings. Decomposing the attention matrix and inspecting its spectrum suggests that negative eigenvalues play a key role in self-suppression. Moreover, this behaviour can be steered by adjusting the spectrum, pointing to a possible causal link between spectral structure and function. These results add to our grasp of attention in LLMs and hopefully hint at new ways to interpret and steer their internal workings.<hr><blockquote>My appreciation goes to David Quarel, Indro Spinelli, Michele Mignani, Lorenzo Venieri, and Simone Facchiano, whose insights and review greatly improved this article. I'm also grateful to <a href="https://www.arena.education/">ARENA 5.0</a> for creating an environment that encourages exploration and growth.</blockquote><a href="https://github.com/Mamiglia/deep-dive-L1H5"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wxPvdBwWeaneAsWRB/hyms8hzjykogo78d9mxy" alt="Github"></a> <a href="https://mamiglia.github.io/deep-dive-L1H5/"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wxPvdBwWeaneAsWRB/wvfvnky6wxsjn8ssdqcp" alt="Viz"></a> <a href="https://mamiglia.github.io/deep-dive-L1H5/attention_pattern.html"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wxPvdBwWeaneAsWRB/hgrnh0g0ebzv6kwwfn6k" alt="Viz"></a><ol class="footnote-section footnotes" data-footnote-section="" role="doc-endnotes"><li class="footnote-item" data-footnote-item="" data-footnote-index="1" data-footnote-id="hwjm6n1hh9q" role="doc-endnote" id="fnhwjm6n1hh9q"><a href="#fnrefhwjm6n1hh9q">^</a><div class="footnote-content" data-footnote-content="">Layer 1, Head 5</div></li><li class="footnote-item" data-footnote-item="" data-footnote-index="2" data-footnote-id="mllnrye5z4" role="doc-endnote" id="fnmllnrye5z4"><a href="#fnrefmllnrye5z4">^</a><div class="footnote-content" data-footnote-content="">An activation patching technique where the activations are replaced with their mean across tokens. <a href="https://www.neelnanda.io/mechanistic-interpretability/glossary#:~:text=Ablation%20aka%20Knockout">Glossary</a>, <a href="https://arxiv.org/abs/2404.15255v1">How to use and interpret activation patching</a></div></li><li class="footnote-item" data-footnote-item="" data-footnote-index="3" data-footnote-id="7lauxepfh7r" role="doc-endnote" id="fn7lauxepfh7r"><a href="#fnref7lauxepfh7r">^</a><div class="footnote-content" data-footnote-content=""><a href="https://en.wikipedia.org/wiki/Leiden_algorithm">https://en.wikipedia.org/wiki/Leiden_algorithm</a> </div></li><li class="footnote-item" data-footnote-item="" data-footnote-index="4" data-footnote-id="n9zeezzzn1e" role="doc-endnote" id="fnn9zeezzzn1e"><a href="#fnrefn9zeezzzn1e">^</a><div class="footnote-content" data-footnote-content=""><a href="https://mamiglia.github.io/deep-dive-L1H5">https://mamiglia.github.io/deep-dive-L1H5</a> </div></li></ol> <a href="https://www.lesswrong.com/posts/wxPvdBwWeaneAsWRB/the-self-hating-attention-head-a-deep-dive-in-gpt-2-1#comments">Discuss</a>]]></description><link>https://www.lesswrong.com/posts/wxPvdBwWeaneAsWRB/the-self-hating-attention-head-a-deep-dive-in-gpt-2-1</link><guid isPermaLink="false">wxPvdBwWeaneAsWRB</guid><dc:creator><![CDATA[Matteo Migliarini]]></dc:creator><pubDate>Fri, 04 Jul 2025 13:31:01 GMT</pubDate></item><item><title><![CDATA[How AI researchers define AI sentience? Participate in the poll]]></title><description><![CDATA[Published on July 4, 2025 12:29 PM GMT TLDR: AI researchers may have a different intuitive definition of sentience than neuroscientists; if you are one of the AI researchers (or policymakers, also important), please consider suggesting your definition in the <a href="https://docs.google.com/forms/d/e/1FAIpQLSfl5Fr4rg8FILb7mQ8RaS6EbBPuYK3ZCPxP2VeWB1Wl1X1ihQ/viewform">poll here</a>. The question of whether AI is sentient, and what criteria can establish this, gets more and more attention lately. Usually, people who discuss this question are either doing it from a general philosophical perspective, or from a neuroscience perspective. However, philosophers and neuroscientists will not be the people who will make a decision about AI development, how it can be trained, which experiments can be conducted, etc. This will be mostly done inside the AI labs, and, potentially, policymakers will also have a word there. Thus, it is important to see what AI researchers think about AI sentience, since the decision will be theirs. It is reasonable to assume that AI researchers do not completely dismiss the possibility of AI sentience. For example, some Anthropic researchers even estimate the probability that the current version of Claude <a href="https://www.datastudios.org/post/could-claude-be-conscious-anthropic-opens-new-frontiers-in-ai-ethics">is sentient to 15% . </a>Should the definition of AI researchers differ from that of neuroscientists or philosophers? After all, won't AI researchers who worry about this question just study the current agenda? This is a valid assumption, but studying does not mean agreeing. As an example, one of the common theories of consciousness in neuroscience is <a href="https://en.wikipedia.org/wiki/Global_workspace_theory">Global Workspace Theory</a>.  Inspired by this model,  a group of researchers built a <a href="https://escholarship.org/uc/item/2g55b9xx">perceiver architecture</a><a href="https://escholarship.org/uc/item/2g55b9xx,">,</a> which satisfies the minimal criteria of consciousness according to this model - yet nobody seems to treat it as a sentient being. So it means that Global Workspace Theory, from the point of view of most AI researchers, is not enough for AI to be sentient. I think it would be very interesting to see what the actual minimal criteria of consciousness/sentience are, according to AI researchers. (So that if you see it in your model, you would treat it as a sentient being). So if you AI researcher or policymaker - please take <a href="https://docs.google.com/forms/d/e/1FAIpQLSfl5Fr4rg8FILb7mQ8RaS6EbBPuYK3ZCPxP2VeWB1Wl1X1ihQ/viewform">the poll</a>, and later I will summarize the results in another post.    <a href="https://www.lesswrong.com/posts/qc9cviDfKYGuqZivy/how-ai-researchers-define-ai-sentience-participate-in-the#comments">Discuss</a>]]></description><link>https://www.lesswrong.com/posts/qc9cviDfKYGuqZivy/how-ai-researchers-define-ai-sentience-participate-in-the</link><guid isPermaLink="false">qc9cviDfKYGuqZivy</guid><dc:creator><![CDATA[Valentin2026]]></dc:creator><pubDate>Fri, 04 Jul 2025 12:29:25 GMT</pubDate></item><item><title><![CDATA[Housing Roundup #12]]></title><description><![CDATA[Published on July 4, 2025 12:10 PM GMT Abundance and YIMBY are on the march. Things are looking good. The wins are each small, but every little bit helps. There are lots of different little things you can do. In theory you have to worry about a homeostatic model where solving some problems causes locals to double down on other barriers, but this seems to not be what we see.
There are definitely important exceptions. Los Angeles is not so interested in rebuilding from the fires and backpaddled the moment developers started to actually build 100% affordable housing because somehow that was a bad thing. New York’s democratic party nominated who they nominated. Massachusetts wants to seal eviction records.
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Overall, though, it’s hard not to be hopeful right now. Even when we see bad policies, they are couched increasingly in the rhetoric of good goals and policies. In the long term, that leads to wins.
I’ll start with general notes, then take a tour around the nation and world.
<h4>Rent Control</h4>
At some point a tenant with rent control effectively owns the apartment, but they and their family are forced to live there forever, including for two years before each time the apartment is passed down.
<blockquote><a href="https://x.com/MattZeitlin/status/1925153857916621246">Matthew Zeitlin</a>: <a href="https://gothamist.com/news/4th-generation-resident-of-rent-stabilized-manhattan-apartment-fights-eviction">classic landlord vs (fourth generational) rent stabilized tenant in nyc story</a>. The interesting wrinkle is that even if the landlord can get the tenant evicted, they can’t raise the rent *unless it’s to a subsidized tenant.*
<a href="https://x.com/christianbrits/status/1925156447517630590">Christian Britschg</a>i: A rent control law that lets family members pass down units to their children is very obviously a physical taking. SCOTUS had an opportunity to rule on this question last year but punted.
As I covered in my newsletter yesterday, there is chance they might take up a similar physical takings claim case challenging LA’s eviction moratorium. Not directly about NYC rent control but could make future challenges easier.</blockquote>
There’s also the crazy part where a subsidized tenant will pay triple the rent a non-subsidized tenant would if the apartment got freed up. And yes, they also put up enough barriers that selling the apartment also is not a practical option.
<a href="https://x.com/MattZeitlin/status/1928818862897717482">Thus you get stories like this rent controlled building selling at a 97% discoun</a>t, or $9,827 per unit. The new buyer is presumably gambling on finding or being given some way to free the building, which I assume will operate at a loss and would be uneconomical to repair properly.
If you are a New York City voter in the coming general election, consider that one candidate in particular wants to double down on this strategy.
<h4>Affordable Housing</h4>
This term has done so, so much damage. Even if affordable housing was ‘a thing’ in that it was housing that was affordable, ‘non-affordable’ housing would still make all housing more affordable, and some affordable units is always better than no units.
<blockquote><a href="https://x.com/zdch/status/1924802188687090090">Misha</a>: It’s amazing how a simple phrase like “affordable housing” is actually a potent brain poison that renders society way worse
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Dan Livingston: It’s a legally defined term. Not a general concept.
Misha: Yes that’s part of the process by which makes society worse off
Zac Hill: In addition to all the [obvious etc], even on the claim’s own terms, aren’t 17 ‘affordable’ units better than the previous state of 0 ‘affordable’ units?
samstod: This is sort of like how everyone seems to complain they are only building luxury apartment buildings, and then lobby for stuff like 800 sq feet minimum, full kitchen, and a parking spot for studios. “Why do they keep building 1200 sq ft 2 bedrooms?”</blockquote>
<a href="https://marginalrevolution.com/marginalrevolution/2025/05/affordable-housing-is-almost-pointless.html?utm_source=rss&utm_medium=rss&utm_campaign=affordable-housing-is-almost-pointless">The thing is, it’s often so much worse than that</a>.
<blockquote>Alex Tabarrok: Affordable Housing Is Almost Pointless
What is the most important feature of affordable housing? Simple! It’s right there in the name, right? Affordable. But no. When the Illinois Housing Development Authority (IHDA) evaluates housing projects for tax credits it <a href="https://www.ihda.org/wp-content/uploads/2023/10/FINAL-QAP_2024-2025-for-website.pdf">gives out points</a> for desirable projects. Quoting <a href="https://citythatworks.substack.com/p/a-better-way-to-build-affordable">Richard Day</a>:
Richard Day: For the general scoring track, 10% of points are awarded for extra accessibility features, 13% are awarded for additional energy efficiency criteria, 15% are awarded based on the makeup of the development team, and an extra 4% are headed out to non-profit developers. Only 3% of scorecard points are awarded based on project cost.
…
This is what Ezra Klein calls <a href="https://www.nytimes.com/2023/04/02/opinion/democrats-liberalism.html">Everything Bagel Liberalism</a> and what I called in one of my favorite posts the <a href="https://marginalrevolution.com/marginalrevolution/2015/07/the-happy-meal-fallacy.html">Happy Meal Fallacy</a>.
The icing on the cake, by the way, is that <a href="https://citythatworks.substack.com/p/a-better-way-to-build-affordable">Day argues</a> that the IHDA is a better system than the even more convoluted and expensive system for affordable housing promoted by Chicago’s Department of Housing.
<a href="https://x.com/scottlincicome/status/1926641830214410678">Arpit Gupta</a>: I didn’t realize that a basic reason affordable housing costs so much is that the actual cost carries such a low weight in winning the bid.
Scott Lincicome: Incentives matter. And politicians’ incentives are often different from those of consumers, producers, & investors.</blockquote>
The job of affordable housing needs to be to make available housing at a low price point. Remarkably often, the projects do not even do that.
<blockquote><a href="https://x.com/SethBurn/status/1931004190186217477">Seth Burn</a>: Coase wept.
<a href="https://x.com/maxdubler/status/1930996792541225275">Max Dubler</a>: A publicly funded affordable housing project came in at $800,000/unit [all one bedrooms]. <a href="https://www.washingtonpost.com/dc-md-va/2025/06/06/these-publicly-funded-homes-poor-cost-12-million-each-develop/">The same developer built a mostly market rate building NEXT DOOR for $350,000/unit</a>.
<a href="https://x.com/AlecStapp/status/1931019622217548248">Alec Stapp</a>: In a better world, spending $1 million per unit to build affordable housing would be the kind of scandal that causes public officials to resign from office.
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That housing might be many things. <a href="https://x.com/AlecStapp/status/1931019622217548248">It is not affordable</a>. What is happening? Again, lots of different interest groups and demands to meet other goals drive up prices.
<a href="https://x.com/ArmandDoma/status/1931743567346823279">Meanwhile, even when you do go ‘100% affordable housing’</a> near a major transit stop you can still get progressive nonprofits opposing it because it might cast a bit of shadow on a nearby schoolyard, <a href="https://x.com/urbanistvc/status/1931751949315260521">while at least two parents there say ‘our schoolyard nadly needs more shade</a>.’
<blockquote><a href="https://x.com/Scott_Wiener/status/1936467380512968822">State Senator Scott Weiner</a>: Certain activists fought market-rate housing in the Mission, arguing it had to be 100% affordable housing.
2 Mission orgs then proposed 100% affordable & the same activists are fighting it.
It’s never been about “affordable housing.” It’s always been about straight-up NIMBYism.
There’s always a reason to oppose new housing for these folks. It’s just a matter of finding the rationale of the day.</blockquote>
Even worse is ‘inclusionary zoning’ which as I understand it is purely a requirement that some percentage of new apartments have to be rented at loss. If you think of this as a tax and redistribution scheme, because that is exactly what it is, it is obvious that this makes absolutely no sense as a way of achieving any goal other than preventing housing construction or enabling corruption.
<blockquote>Max Dubler: So-called “Inclusionary Zoning”—the practice of requiring homebuilders to rent some percentage of new apartments at a loss—is bad policy that lets elected Democrats pretend to care about poor people while NIMBYing new housing, worsening the housing shortage, and raising rents.
<a href="https://x.com/thuddwhirr/status/1929786927487520976">John Wilthui</a>s: When I explain IZ to folks who are new to the housing issue, I have to repeat the part about how it’s unsubsidized, because nobody believes it on first telling.</blockquote>
It does make sense to potentially tax new housing construction if and only if you have otherwise already restricted the ability to build in ways that mean that building is highly profitable but the ability to get permission to build is fixed. In that case, if you’re locked into the first half of that decision you might as well collect the fees I guess, but you should just charge them money.
<h4>A Vision</h4>
<blockquote><a href="https://x.com/RepealTCPA1947/status/1902862231756214504">Josh</a> (370k views so fair game): abundance agenda urban planners have no capacity to understand that the profession cannot exist if development is deregulated. we literally maintain regulations, that’s what planning is. this is not the best era to advocate for your own unemployment.
YIMBY Martial Law Enforcer:
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<h4>Private Equity</h4>
Why is it that the term ‘private equity’ makes people lose their minds? Admittedly this is an extreme case, but the less crazy versions aren’t conceptually different.
<blockquote><a href="https://x.com/RealJMcAfreak/status/1927941482339528937">JMac:</a> It doesn’t matter. Private Equity will buy them all up the moment they hit market. You could build a house for every man, woman, and child, and Private Equity would buy them all up and rent them out. House availability is not and never was the problem.
House gets built
House hits market
Private Equity buys house
Private Equity rents house out.
This is how it goes. This is how it’s gone ever since Trump repealed the Obama-era law barring companies from buying residential properties for the first year on market.</blockquote>
So let me get this straight. You build a house for every man, woman, and child, far more houses than people want to live in. Then mysterious ‘private equity’ buys them all, and then they charge what, exactly? They all form a conspiracy to set prices at a monopoly level and no one notices? One PE company buys all the nation’s housing stock? Something else?
<h4>Home for Rent</h4>
<a href="https://marginalrevolution.com/marginalrevolution/2025/03/institutional-ownership-of-single-family-housing.html?utm_source=rss&utm_medium=rss&utm_campaign=institutional-ownership-of-single-family-housing">Tyler Cowen</a> brings us this <a href="https://felipebarbieri.com/files/Barbieri_Felipe_JMP.pdf">job market paper</a> from <a href="https://felipebarbieri.com/">Felix Barbieri</a> via <a href="https://x.com/qlquanle">Quan Le</a> about the impact of institutional ownership on the rental market, with supply effects proving larger than concentration effects:
<blockquote>In the last decade, large financial institutions in the United States have purchased hundreds of thousands of homes and converted them to rentals. This paper studies the welfare consequences of institutional ownership of single-family housing.
We build an equilibrium model of the housing market with two sectors: rental and homeownership. The model captures two key forces from institutional purchases of homes: changes in rental concentration and reallocation of housing stock across sectors.
To estimate the model, we construct a novel dataset of individual homes in metropolitan Atlanta, identifying institutional owners of each house and scraping house-level daily prices, rents, vacancies, web page views, and customer contacts from Zillow.
We find that institutional acquisitions increase average renter welfare by $2,760 per year (with rents decreasing by 2.3%). This net benefit reflects two opposing effects: higher concentration raises rents by 3.8%, but higher rental supply lowers rents by 6.1%. On the other hand, the welfare of the average home buyer decreases by $49,950. On the supply side, institutional acquisitions benefit house sellers but harm the average landlord.</blockquote>
I noticed I was confused. o3 explained that the average annual rent was $28k but that reduced search frictions and greater choice meant that the overall benefit was ~10% of the rent. That seems like a lot, and reminds me of a lot of economist talk of ‘well you have greater product variety or are forced to buy more [X] so you’re actually fine and totally not poorer.’
It’s not totally impossible the benefits are this big, if the rent market was previously super thin, and before there would be highly slim pickings, especially in the exact right location and size. When I rented in Warwick, there was a clearly best house, and if I’d had to go with my second choice I do think I’d have faced a >10% welfare hit, as in if they’d asked for 10% more rent we’d cheerfully have taken it anyway.
10% still does seem like a lot in general.
By o3’s calculation there are about 30x times as many people renting in a given year as buying that year, so this is a clear net gain, even if you don’t count that often individual sellers pick up that extra $50k that the buyers pay (and they at least partly reclaim it when they sell). So this is good unless you strongly want more people to own on the margin instead of rent, and given mobility concerns my guess is we want more renting than we have in such areas.
<h4>Making Housing Worse On Purpose So You Can Click</h4>
<a href="https://x.com/CatholicCharm/status/1927154619085447667">Here’s another bizarre mind worm</a>, mostly for fun this time:
<blockquote>Catholic Charm: Boomers are selling their houses for high prices and then downsizing and paying for starter homes with cash. So young families can’t afford the homes they’re putting for sale and then get outbid the houses they can afford. They’ve totally ruined the market it’s insane.
Well, the issue is the concept of a starter home is a common thing now because people can’t afford a house that meets their needs. They’re buying houses that they’ve already outgrown or know they will outgrow in a few years because they can’t afford a home they can grow into.
I have no issue with older people staying in their current homes, that’s what I plan to do.</blockquote>
You see, if the old people consume more house, then that’s good for everyone else’s ability to ‘afford’ houses because those houses are expensive. But if they downsize to less house, thus making more housing available for others, that’s bad, because they took away the cheap houses. Wowie.
The generalization of this is fascinating. There are a lot of people who think:
<ol>
<li>Affordable housing is good.</li>
<li>Making housing better makes it less affordable.</li>
<li>Therefore make sure people don’t make housing better.</li>
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This covers renovations, and gentrification, and more.
There is actually a great instinct behind this, which is that it would be great if we could allow people on tight budgets to ‘buy less house’ and still have a house, in terms of both quality and quantity. Because those people would be better off buying smaller lower quality houses.
And that’s right about that! Improving houses obviously makes people on net better off, as willingness to pay goes up for a reason, but if quantity of units is fixed those particular people would benefit from the available housing stock staying worse.
The thing is, it would be very easy to give it to them. All you have to do is allow people to choose to build or rent out smaller housing, and crappier housing, if everyone involved wants to do that. Legalize smaller rooms, smaller apartments and single room occupancy. Create a new class of amenities so that some are ‘required’ but others currently required are ‘standard’ such that you have to disclose and put in the rental or sales contract that they’re missing and point this out verbally, but make it legal to waive them if the tenant or buyer wants that.
We could very easily create a world in which those struggling with expenses could make modest but manageable sacrifices and be able to live where they need to live. We choose not to do that.
<h4>Open Philanthropy Strikes Again</h4>
This seems great.
<blockquote><a href="https://x.com/albrgr/status/1899476673248231885">Alexander Berger</a> (CEO OpenPhil): <a href="https://t.co/uQ2MpnOOB2">Exciting update: @open_phil is doubling down on our YIMBY, innovation, and metascience success</a> by launching a >$120m Abundance & Growth Fund to accelerate economic growth and boost scientific & technological progress. Funding from @GoodVentures, @patrickc, + others.
Scientific and technological progress drive long-run prosperity. @bfjo & @LHSummers estimate that *new ideas* account for ~50% of US per-capita GDP growth, with social returns of $14 for each $1 invested in R&D.
…
Luckily, these challenges are tractable. Through our decade of funding YIMBY housing reform, we’ve seen that policy advocacy can make a real difference (so far, especially on ADUs).
Now is the time: across the political spectrum, there’s growing recognition of the need to address these constraints. Both parties have members advocating for housing abundance, energy abundance, and reduced bureaucratic barriers to innovation, presenting a unique opportunity.</blockquote>
<h4>The Abundance Debate</h4>
Aaron Regunberg offered some substantive critiques of the general abundance agenda, <a href="https://x.com/JHWeissmann/status/1921941245665968192">Jordan Weissmann delivers continuous knockout blows in return</a>, as the arguments amount to ‘there are various factors [X] and [Y] making things worse, you only deal with [X] not [Y]’ to which the answer is, ‘actually we also are working on [Y] and also [Y] often acts through [X], and also [X] alone would help what is the issue.’
I want to be clear that this is not me picking on Aaron. This is me picking out the best and most substantive critique, because the other critiques are worse.
As the results add up, the vibes are clearly shifting. I am here for it. Daniel’s comment here is Obvious Nonsense. Green New Deal and Socialist rhetoric in general says it is ‘abundance’ because they assert their policies will somehow lead to everyone having all the things except the bad people who shouldn’t have them, except no it is a shame but actually that’s not how the world works. The choice of rhetoric is telling and it is bizarre how everyone can suddenly shift into ‘abundance was always good politics’ mode. In which case, yes, happy to nod.
<blockquote><a href="https://x.com/aldatweets/status/1934343990650011998">Daniel Cohen</a>: The Ezra-Abundance discourse was a centrist co-optation of the Green New Deal’s original abundance politics. Now Zohran is taking it back for the left. Not sure why so many people are surprised… #Abundance: welcome home.
<a href="https://x.com/DKThomp/status/1934700798572695777">Derek Thompson</a>: The rapid online shift from “abundance is obviously shit politics“ to “abundance is obviously great politics, and it was our idea first, and now we got it back!” is a nice reminder that people are just making up discourse on the fly, and the book is still just 13 weeks old and, like everything else in the world, nobody knows how this is going to turn out.</blockquote>
It is so funny that Zohran is presenting as an abundance candidate while trying to do so many obviously anti-abundance things, especially vast imposition of greater rent controls and other requirements on those who would actually build or rent housing but also many other socialist policies. It is still great progress. I want everyone to have to acknowledge that abundance is the goal, even if they have no intention of doing things that cause abundance. Then it’s on us to point this out.
<blockquote><a href="https://x.com/ProfDBernstein/status/1938279917101445169">David Mamandi:</a> According to Mamadani, the city won’t “slow down” new private housing projects. All the developers need to do are meet his criteria for
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<li>Affordability</li>
<li>Rent-increase limitations</li>
<li>Union labor</li>
<li>Sustainability.</li>
<li>At that point developers are free to …. wait, no, they still need to go through “land use review.” LOL!</li>
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Mamendani: That means when private developers come to me with a plan that meets our goals around affordability, rent-stabilization, union labor and sustainability, it will be fast tracked through land use review. The days of the city slowing projects down are over.</blockquote>
Yeah, if he gets to be mayor we’re not building all that housing.
<h4>Single Staircase Apartment Buildings</h4>
It’s happening. No, I don’t think Austin will get tired of all this winning.
<blockquote><a href="https://x.com/AURAatx/status/1910396115393917012">AURA</a>: Austin City Council votes 10-1 to legalize 5-story single-stair apartments, making Austin the largest US city outside of NYC to legalize single-stair! <img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/FAnxq8wFpfqGjeetC/llw6ztvuutmakrbsh0bt" alt="🎉" style="height:1em;max-height:1em"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/FAnxq8wFpfqGjeetC/llw6ztvuutmakrbsh0bt" alt="🎉" style="height:1em;max-height:1em"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/FAnxq8wFpfqGjeetC/llw6ztvuutmakrbsh0bt" alt="🎉" style="height:1em;max-height:1em">
Many thanks to all the supporters and to @CMChitoVela for leading this exciting reform! We did it y’all! <img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/2azxasXxuhXvGfdW2/p1dqsfpeon3rhfbl08v6" alt="🙌" style="height:1em;max-height:1em"></blockquote>
<a href="https://x.com/GovofCO/status/1897829560093200494">It’s not happening in Colorado</a> yet but the governor is calling for it.
<blockquote>Jared Polis (Governor of Colorado): In Colorado, we are laser-focused on cutting housing costs and increasing the supply of new housing that Coloradans can afford. In my State of the State address, I called for Smart Stair reform to increase the supply of housing people can afford in the neighborhoods where people want to live near transit and job centers.
This new study shows that smart stair buildings are less costly to build and are safer.
<a href="https://x.com/hktsre/status/1895534934061953424">hek!</a>: single stair midrises aren’t more dangerous!! Pew Research study looked at fire risk in single stair buildings. this matters because most US/Canadian cities require double stair: consuming ~10% additional space just for stairs and increasing costs up to 13%!
these costs + standard USA zoning issues means that it’s really hard to build these mid rises – even if they’re extremely desirable AND when we do build them, they are frequently suboptimal for humans + over priced
Paris is filled with Haussmannian 6 story complexes – surprisingly denser than NYC!
*liberal definition of metro vs city used here lmao</blockquote>
<a href="https://x.com/maustermuhle/status/1912147781667405834">There’s also a bill that’s been introduced in DC</a>, which also includes a single exit.
This change alone would solve so many problems. The second stair has never made physical sense, the Europeans and others around the world use single stair with no issues, and now we crunched the numbers and we now the second staircase takes up a huge percentage of the building without making anyone safer.
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Put it another way. The second staircase reduces space by 10% and raises costs by 13%. How many people would pay an extra 10% in rent to have a second staircase? It’s hard for me to imagine many making that choice.
Why didn’t it happen sooner? <a href="https://x.com/aarmlovi/status/1927541502546260224">This seems a little harsh, but only a little</a>:
<blockquote>Alex Armlovich:
<ol>
<li>Be careful when you find buried treasure out in the open. It could be a trap or an illusion</li>
<li>Essentially nobody in the last century in the US checked if 2 staircases are necessary for apartment buildings until 2021. Now a dozen states have changed. Which is pretty insane</li>
</ol>
Before Single Stair Twitter, there was one lonely architect in Toronto who was like “uh you guys nobody else in the world does it like this” but his op-ed was completely ignored
He didn’t have a YIMBY movement around back then to help, he was just one lonely smart guy <img src="https://s0.wp.com/wp-content/mu-plugins/wpcom-smileys/twemoji/2/72x72/1fae1.png" alt="🫡" style="height:1em;max-height:1em"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/6yoehDfWJAgnRHpWo/fw2mdkwfhba4rsgxle1f" alt="😭" style="height:1em;max-height:1em">
This is good example of our anonymous Canadian hero from the replies!
I seem to also recall an oped in the Globe or the Toronto Star, or some paper of record in Toronto</blockquote>
<h4>Dublin</h4>
<a href="https://x.com/Sam_Dumitriu/status/1902328791277461878">It seems Ireland forces only 25% of net growth to go to Dublin</a> and its suburbs, <a href="https://t.co/4abvMWxIsN">so up to 2040 Dublin is only permitted to grow at 20%-25%</a> total. This is of course exactly the opposite of what would make everyone better off, as evidenced by everyone wanting to move to Dublin, instead its population was lower in 1991 than 1911.
<h4>Western Housing Costs</h4>
<a href="https://www.construction-physics.com/p/why-are-homes-in-western-states-so">Brian Botter asks what explains this graph</a>, where housing in the West is super unaffordable relative to income.
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He rules out lot sizes, and construction cost differences are only moderate. It is clearly supply and demand, people want to move West (and South), the amenity index explains part of why, and demand can’t keep up (the version of this map he has is interactive).
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The West has grown in population 27% since 2000 versus 20% for America, despite California’s best efforts, and if not for lack of housing it would have grown a lot more. This is all about inability to build more housing where people want to live, in particular because we are not legally permitting people to do so. That’s it.
<h4>Los Angeles</h4>
<a href="https://x.com/AlecStapp/status/1909597053530845588">Ah yes, that time the Mayor of Los Angeles</a>, who it seems can Just Do Things, <a href="https://www.slowboring.com/p/how-will-we-know-if-abundance-is?publication_id=159185&utm_campaign=email-post-title&r=lopb&utm_medium=email">issued an executive directive making it fast and easy to build 100% affordable housing</a> with zero government subsidies, then furiously backpaddled when developers started building.
<a href="https://x.com/CollinRugg/status/1898865578762498160">Meanwhile, LA is forcing Simpsons producer Rick Polizz</a>i to demolish his 24-year-old Simpsons-inspired treehouse after LA demanded it be permitted like a ‘single-family dwelling.’ This happened after the fires.
<blockquote>Collin Rugg: Attorney Paige Gosney says they secured zoning permits in 2023 but can’t get building permits from the Department of Building and Safety. “Staff wanted soil reports, structural designs, Americans With Disabilities Act compliance and all this stuff that is just kind of absurd,” Gosney said.</blockquote>
<h4>LA Fire</h4>
<a href="https://x.com/cremieuxrecueil/status/1902817307291947425">Meanwhile, LA is making everyone suffer to even rebuild the exact same house</a> that burned down, let alone build something new that is better. They’re torturing them less than they usually torture builders, but that isn’t saying much.
<blockquote>Cremieux: It’s almost unbelievable that California requires you to file for permits galore to rebuild the exact same home that was there before on a burned down plot.
It’s hard to find anyone who seriously thinks this is acceptable.
Garrett: I was just talking about this today with a builder who lost their home in the Palisades Fire. Not only do they have to file for the permits, they are making them pay for them after everything they’ve been through which is totally unacceptable imo.
Cremieux: Have been hearing similar. Friend is trying to just sell his plot and move on because he doesn’t think he’ll be able to rebuild for years.
Garrett: They did cut *some* of the red tape for some who are affected, so they don’t have to go through the entire permitting process but it’s still a bit much. I understand why it’s required, but they are so slow and tbh, they should not be charging for it.
They’re not all getting the entire value of their homes and property back and rebuilding a home that one may have had for decades is going to be so much more expensive now. Paying $15-50k+ for permitting is ridiculous when you consider how much in property taxes these folks pay.</blockquote>
Want to Build Back Better? At least you’re not going with the Biden version, <a href="https://x.com/EricAbbenante/status/1905422938352091313">here’s Ezra Klein explaining the 14 steps to apply for that funding</a>, and Jon Stewart slowly realizing how absurd it is, and screaming, among other things, ‘OMFG.’ <a href="https://x.com/BharatRamamurti/status/1905594268460167546">Bharat Ramamurti claims this is a ‘deeply misleading’ clip</a>, that the process was like this because of GOP sabotage and wasn’t the design intention. Even if fully true, I do not feel it makes things that much better.
<blockquote><a href="https://x.com/KelseyTuoc/status/1927420881933930556">Kelsey Piper:</a> ‘We’ve taken action to cut red tape’. ‘Did the action you took….work?’
Kane: Los Angeles has only issued 11 building permits for rebuilding after the fire, but the mayor is claiming with a straight face that “homes are under construction throughout the Palisades”
LA Mayor Karen Bass: Homes are under construction throughout the Palisades — ahead of expectations.
We’ve taken action to cut red tape and expedite the permitting process to get families home.
Kane: It gets worse lmao
Rachel Keuler: Only 1 of those permits is in the Palisades, where Karen Bass says that homes (plural) are under construction.
Zac Hill: “High School Zac Has Taken Action To Get Avril Lavigne’s Phone Number: News At Eleven”</blockquote>
It’s amazing that the claim of ‘homes under constructions’ isn’t even obviously literally true, as in it is not clear there are two of them.
<h4>San Francisco</h4>
<a href="https://x.com/StatisticUrban/status/1913361217051332780">The good news is that by all reports San Francisco is turning itself around</a> on crime and quality of life, such as this report of spending a week seeing few homeless and no broken car windows, feeling fully safe.
Except that means:
<blockquote><a href="https://x.com/StatisticUrban/status/1913361217051332780">Hunter:</a> > SF turns itself around
> Still doesn’t build housing
> $5,000 median rent for a one-bedroom incoming
<a href="https://x.com/ArmandDoma/status/1911110614489116814">Armand Domalewski</a>: Call me crazy but the fact that you need experience navigating San Francisco’s choppy political waters in order to build a small office building does not exactly make our city seem like a welcoming place for investment at a time where we very much need it.
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Instead, they’re taking a bold stance that <a href="https://x.com/DanJohnsonCRE/status/1909736417934426214">phone booths require sprinkler systems</a>. Anyone with a rudimentary ability to think about the physical world understands that this is not motivated by worried about fire.
Last year, <a href="https://x.com/CohenSite/status/1934374394127880211">a Caltrain official built himself an illegal apartment inside a train station for $42k</a>, and now we have pictures. The building already existed, so no even without legal issues you cannot simply build more of these, but yes we want a full explanation.
<blockquote>Sheel Mohnot: We finally have images of this apartment! A Caltrain official secretly built himself a hidden unit inside Burlingame station using $42k of public funds. It looks like a dorm room / a startup founders 1st office.
Armand Domalewski: I am genuinely curious why he was able to build this for $42k a unit. What costs did he avoid that he couldn’t avoid if he did this legally? If CA could build $42k unit studios we’d end homelessness in a year.
Debra Cleaver: for starters, the building itself already existed, and presumably was plumbed and wired for electricity. So I imagine he added furniture, appliances and made some sheetrock to divide the space?
Armand Domalewski: That is true for all modern office buildings yet office to apartment conversions are notoriously expensive.
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Joe Cohen: Everyone’s response: “it’s impressive what he was able to do with $42k. Maybe he should be put in charge of CA housing.”</blockquote>
Each little requirement for apartments seems like a good idea, but add them all up and the costs involved escalate quickly. I wonder if what we should do is actively have a two-class housing structure (yes I know, young adult dystopian writers, eat your hearts out), where you can choose to be in either conforming or non-conforming housing.
<a href="https://x.com/YIMBYLAND/status/1938626989675470998">Berkeley legalizes middle-housing city-wide</a>, eliminating single-family housing, legalizing duplexes, quadplexes and small apartments.
<h4>California</h4>
YIMBY and abundance are scoring some impressive wins in California, including making CEQA (their version of NEPA) not apply to a broad range of housing.
This bill passed the Senate by 62-2. I’ve learned that such votes are remarkably not indicative of how close things were, but it still indicates no one is worried to vote yes.
Gavin Newsom is not holding back. On this issue he’s actually been impressive.
<blockquote>Gavin Newsom (Governor of California): To the NIMBY movement that’s now being replaced by the YIMBY movement, go YIMBYs. Thank you for your abundant mindset. That’s a plug for @ezraklein.
<a href="https://x.com/YIMBYLAND/status/1939876355908223169">Yimbyland</a>: ITS HAPPENING!!!
All new housing projects under 50 units in the state of California will be exempt from CEQA!! The state is finally coming to its senses!
Jerusalem: I honestly can barely believe this happened. Total YIMBY victory in California today. After Newsom signs this bill; CEQA will no longer apply to *any* infill housing under 85’. No inclusionary zoning or labor provisions.
Armand Domalewski:
<ol>
<li>Except for SF projects over 50 units</li>
<li>Except for 100% affordable projects</li>
</ol>
(Both subject to prevailing wage still)
But otherwise yes!!!! :)
Alex Armlovich: It’s a huge deal but I want to manage national expectations of instant Austin-style outcomes until SB79 joins it
Partially rolling back CEQA for housing will make California *almost normal*…but still probably ranked ~44th in the US for enviro review
Elon’s My Hero: Now every building is going to be exactly 84.9 feet tall. That’s going to look… wonderful…</blockquote>
(I notice again how absurd the term ‘prevailing wage’ is, if it’s so prevailing why would you need a law to stop them hiring people for less money? Call the thing by its name, and it’s unclear how big a tax this is on projects or how much it will matter.)
I notice that you don’t actually get ‘every building is 84.9 feet tall’ style outcomes. People don’t actually push zoning options to their limits, people don’t optimize as much as they should.
Having CEQA apply to infill housing, or really almost any residential housing, was always a terrible idea. There are neighbors who can sue, so this interferes with ability to build almost anything. But very obviously, the ‘environmental’ impact of infill housing replacing existing low-value construction is mostly a fake concern. Instead, you drive sprawl, with construction going out into places you can actually do environmental damage, plus you discourage density when density helps a lot with carbon emissions as well, even disregarding the economic impacts.
About SB 79, that was introduced by <a href="https://x.com/maxdubler/status/1912971712960090114">Scott Weiner</a>. It would legalize apartments near mass transit. The standard argument against this is that those new apartments would not be ‘affordable,’ and instead by ‘luxury’ homes. They would be too valuable to the people who live there, who would pay too high a price to reside in them. Oh no.
In the linked thread, Max Dubler makes the argument that they will still be cheaper than buying existing houses. That’s true enough, and if it convinces people, great. But it’s beside the point. The point is that we can build more housing where people want to live, that will be valuable to the people living there, creating lots of value and in turn will drive down rents elsewhere. More housing is good, let people build housing, in the places people want to live, especially where they’ll have access to mass transit.
I do have one worry with such bills. If you say that mass transit causes upzoning, will that cause cities to avoid building mass transit? Given how little mass transit gets built at this point, that’s a risk I am willing to take.
Is 2025 the last chance for California to build housing <a href="https://x.com/IDoTheThinking/status/1914510526446723378">that lets it retain population for the 2030 redistricting</a>, where it is projected to lose five house seats and thus electoral votes, importantly altering what maps win the presidency? Darrell Owens argues building a house takes five years. My presumption is that actually building by that time won’t have much effect on this scale.
But planning to build future housing does already help. Prices are forward looking and rational. So if more housing is coming, current prices should fall in anticipation, or demand should rise knowing it will be easier to stay in the future, in some combination.
<h4>Oregon</h4>
On its face, this seems like a very big deal once the rules work their way through?
<blockquote><a href="https://x.com/andersem/status/1937241766442467756">Michael Andersen</a>: This Oregon bill, the first of its kind in the country that I’m aware of, just passed: 50-2 in the House, 28-2 in the Senate. A lot will depend on rulemaking, but this opens the door to a Japan-like system where the state defines its own version of lower-density zoning codes.
<a href="https://99percentinvisible.org/episode/the-house-that-came-in-the-mail/">It’d pre-approve zoning & building permits</a> for a state-defined catalog of 1-11 unit buildings on standard urban lots. two great laws that go great together.
<a href="https://x.com/AndrewDamitio/status/1937314604406710588">Andrew Damito</a>: Oregon’s legislature just passed HB 2258, which enables the state land use planning agency to preapprove a series of housing designs for structures up to 12 units, and require that cities auto-approve the structures anywhere, with very few exceptions.
WOW!
My thoughts?
<ol>
<li>The law falls into the same trap as other blue-state YIMBY laws as it relies heavily on rulemaking instead of simply vacating local restrictions, meaning we won’t see any regulatory changes for at least a year, and will take longer to see housing emerge from it.</li>
<li>There’s potential for homebuilding productivity increases through industrial scaling. If the state pre-approves prefab & modular housing designs, builders could lower costs through mass production. America’s disparate codes have prevented that.</li>
<li>The Oregon LCDC is very YIMBY, even using its rulemaking powers to end parking minimums in all Oregon cities through its Climate Friendly and Equitable Communities rulemaking in 2023. You can bet that they will be ambitious in pre-approving housing.</li>
<li>@andersem’s optimism that this opens the door to a Japanese-style state abrogation of lower density zoning isn’t unfounded.
This bill doesn’t just require approval of specific housing designs, the state can also set rules requiring approval of variances to the designs.</li>
</ol>
</blockquote>
<h4>Montana</h4>
This all looks like it will add up to a pretty big deal (within Montana).
<blockquote><a href="https://x.com/andersem/status/1915888096325079094">Michael Anderson</a> (April 25): Last week, Montana voted to:
– legalize 6-story apartments on most commercial land
– sharply cut parking mandates
– limit excess impact fees
– cut condo defect liability
– require equal treatment for manufactured homes
– legalize single-stair buildings up to 6 stories statewide
headline we rejected <a href="https://www.sightline.org/2025/04/25/montanas-housing-miracle-strikes-twice/">for this article</a>: “Montana is so YIMBY, it’s getting embarrassing”
A recent study found that eliminating parking minimums alone <a href="https://www.sightline.org/2024/12/10/parking-reform-alone-can-boost-homebuilding-by-40-to-70-percent/">can boost new home construction by 40–70 percent</a>.
Several narrower bills tackle other obstacles to housing construction.
<ul>
<li><a href="https://bills.legmt.gov/#/laws/bill/2/LC1030?open_tab=sum">SB 133</a>, introduced by Senate Majority Leader Greg Hertz (R-Polson), limits the impact fees that cities charge developers, which increase the cost of construction. Specifically, it eliminates administrative fees, caps fees growth to inflation, and limits the imposition of fees to infrastructure projects that are directly linked to a proposed development.</li>
<li>Hertz also successfully ran bills to limit construction defect litigation (<a href="https://bills.legmt.gov/#/laws/bill/2/LC2447?open_tab=sum">SB 143</a>) and transfer decision-making on historical preservation permits from volunteer-run boards to professional city staff (<a href="https://bills.legmt.gov/#/laws/bill/2/LC1016?open_tab=sum">SB 214</a>).</li>
<li><a href="https://bills.legmt.gov/#/laws/bill/2/LC1861?open_tab=sum">SB 252</a>, introduced by Sen. Dave Fern (D-Whitefish), requires cities to treat manufactured homes on equal footing as stick-built construction.</li>
<li><a href="https://bills.legmt.gov/#/laws/bill/2/LC0705?open_tab=sum">SB 532</a>, introduced by Sen. Forrest Mandeville (R-Columbus), allows one ADU by right on parcels outside cities. (Hertz’s <a href="https://legiscan.com/MT/text/SB528/2023">SB 528</a> from the prior session legalized ADUs within cities.)</li>
<li>Finally, <a href="https://bills.legmt.gov/#/laws/bill/2/LC0412?open_tab=sum">SB 213</a>, introduced by Sen. Daniel Zolnikov (R-Billings), puts Montana among states such as Connecticut and Washington that are re-legalizing single-stair residential buildings. SB 213 orders new rules for the state building code to allow for the construction of <a href="https://www.sightline.org/2025/01/08/sunlight-suites-a-simple-change-could-unlock-these-beautiful-homes-photos/">single-stair buildings up to six stories</a> when they meet fire safety standards.</li>
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<h4>Maine</h4>
I too had no idea this one was in the works:
<blockquote><a href="https://x.com/mattyglesias/status/1940518319091863990">Matthew Yglesias</a>: It seems like <a href="https://x.com/mattyglesias/status/1940518319091863990">Maine quietly passed one of the most dramatic statewide upzoning bills</a> I’ve ever heard of without anyone paying much attention.</blockquote>
Here’s what they changed, the big one is up front but the ADU help is great too:
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<li>At least three dwelling units allowed on any residential use lot.</li>
<li>Up to four units where served with water and sewer.</li>
<li>No more sprinkler requirements for most ADUs.</li>
<li>ADUs no longer limited to single family lots or conforming lots, and no longer require owner occupancy.</li>
<li>Subdivision review threshold raised from three units to five.</li>
</ol>
<h4>North Carolina</h4>
<a href="https://x.com/berkie1/status/1938045569911624051">It still needs to get through the Senate and governor</a>, but <a href="https://x.com/mattyglesias/status/1938058329168949348">North Carolina State House unanimously</a> (107-0) passed HB 369, <a href="https://www.axios.com/local/charlotte/2025/03/21/parking-lot-reform-north-carolina-water-pollution">a ban on parking minimums</a> in new developments statewide. You can just prevent people from stopping you from doing things.
<h4>New York City</h4>
In new ‘who could have predicted it news,’ it turns out if you change how people pay the market clearing price doesn’t move and maybe the old system had its advantages? Maybe it was actually a stroke of genius to normalize the renter paying the agents, and we didn’t notice because New York City rent is too damn high despite this?
<blockquote><a href="https://nypost.com/2025/06/21/us-news/rents-jump-shocking-15-after-nyc-ditches-broker-fees/?utm_medium=social&utm_campaign=nypost&utm_source=twitter">Gabrielle Fahmy</a>: Rents jumping shocking 15% after NYC ditches broker fees: ‘It’s discouraging’
Rents shot up a shocking 15% in the week since the <a href="https://nypost.com/2025/05/30/us-news/nyc-broker-fee-law-which-protects-tenants-from-costs-challenged-by-real-estate-agents-in-11th-hour-push/">controversial FARE Act took effect</a>, with the average rental in the Big Apple jumping from $4,750 to $5,500, according to an analysis by real estate analytics firm <a href="https://www.urbandigs.com/">UrbanDigs</a>.
The FARE Act, which prohibits agents representing property owners from charging renters a “broker fee,” also requires that all fees a tenant owes be included in rental agreements and real estate listings.
The law change has created what insiders tell The Post is a “shadow market” — apartments that aren’t listed so landlords can still get tenants to cover the fee.
“We’re going to be looking for apartments again like it’s 1999 … where you have to know who to call and when to call,” said Jason Haber, co-founder of the American Real Estate Association and a broker at Compass. “It’s going to be an odyssey.”
<a href="https://nypost.com/2025/06/20/us-news/nycs-new-broker-fee-law-already-being-flouted-by-sneaky-real-estate-agents-tenants-say-exploiting-a-loophole/">Renters meanwhile have been sharing horror stories online</a>, with receipts — like screenshots of conversations with brokers flat out telling them they get one price if they pay the broker fee and another, much higher rate, if they don’t.
…
Another said a landlord was asking $6,800 for a 3-bedroom with a broker fee — or $8,000 with no fee, which is illegal to advertise under the new law.
Karol Makowicz: Who could have seen this coming.
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Typical broker fee is 15% of rent, getting rid of that fee on a one year least meant rent went up 15%, wow, who could have predicted this. The average lease lasts 3-4 years, in theory the price should drop back down for future years.
I presume it mostly won’t and tenants are in general a lot worse off now. There is some value in getting that up front payment up front, but it’s clearly not worth the marginal price that has attached. So we had this great trick, and it is gone now. Damn.
Meanwhile, we’ve managed to get rid of parking requirements in the full core, but they alas live on in much of the city, so this is a chart of where you want to live in New York City, be in the blue area, or at least be in yellow. Red doesn’t even count, that’s suburbs.
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Also, yes it would help if <a href="https://x.com/jbarro/status/1940804643514368114">New York didn’t require all elevators</a> be large enough to let a wheelchair turn around. I get that it’s nice to be able to do that but this actually substantially raises construction costs, and wheelchairs can go backwards.
<h4>Massachusetts</h4>
<a href="https://x.com/stanfordNYC/status/1919892213271556250">No, you fools!</a>
<blockquote>Bernard Stanford: This is the equivalent of taxing everyone who pays their rent to fund a subsidy program for people who decide they’d rather not.
Gintautas Dumcius: Eviction records can now be sealed in Massachusetts.
Bernard Stanford: If “one tough chapter” doesn’t bare on a person’s future, but landlords are sub-optimally biased, then the state could step on with an insurance scheme and provide benefit while profiting.
…
Even cases of actual misconduct, not simply failure to pay, are eligible to be sealed! Landlords don’t have the right to know whether a prospective tenant was violent or threatening towards a past landlord? Note that criminal records are also sealable in Massachusetts.
The ultimate consequence is quite simple:
<ol>
<li>The added costs and dangers of being a landlord increase</li>
<li>At the margin, landlords will sell rental properties to become SFH, or opt not to purchase new construction to rent, or opt not to buy buildings and convert them to rentals</li>
<li>The availability of rentals decreases</li>
<li>Due to scarcity, average rent rises</li>
</ol>
Hence everybody pays more and is worse off, except those who welch on their rent or break the terms of their lease and get evicted, who are now relieved of some of the consequences of their past actions.
Adam Rezabek: There is also another consequence: landlords will have to use all stereotypes known to men to try and guess which prospective tenant will be an issue and which will be not. Ofc this isn’t legal, but I think it will happen regardless</blockquote>
Do not underestimate the effect Rezabek refers to. I remember that ‘ban the box’ rules that prevented checking job applicants for criminal records similarly ended up hurting exactly the groups with criminal records, because of updates on (lack of) evidence. A similar pattern will no doubt happen here, on all correlations, legal or otherwise.
This also likely decreases new constructions outright.
Mostly it increases rents and moves a lot of rental stock off the market. I do expect a substantial impact here. A bad renter is expensive. Now, not only can you not filter out past bad renters, renters know that if they defect they can have their records sealed. So not only do you get negative selection, everyone will behave way worse.
<h4>Texas</h4>
There’s some great bills passing that would be awesome as national standards.
<blockquote><a href="https://x.com/YIMBYLAND/status/1927854096079262124">YIMBYLAND</a>: SMALL LOT STARTER HOMES PASSES IN TEXAS AFTER NEARLY DYING
– 3,000 sf lots
– 31 units/acre by-right in SF zones
– 5′ max setbacks
– Limits parking mandates to 1 space/unit, no carport mandates
– Developers can sue for delays, cities pay damages
– 5 acres required for development</blockquote>
This is a neutered version of the bill, but it’s still a great start.
<blockquote><a href="https://x.com/YIMBYLAND/status/1927420910350270573">YIMBYLAND</a>: TEXAS PASSES 6-STORY SINGLE-STAIR BILL! <img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wuoTsXoe93mXavofB/b15mndye7scndtidiwmv" alt="🤠" style="height:1em;max-height:1em">
– Legalizes 6-stories, 4-units/floor, in TX state building code
– Cities that adopt standard amendments to state building code would by-default legalize 6-story single-stair apartments
– Paves way for streamlined adoption by cities
I feel like I’m getting annoying at this point, but this could be you if your state had the courage. It is 100% possible to make real, impactful, housing reforms and Texas is leading the way.</blockquote>
<a href="https://x.com/aarmlovi/status/1924987094671233100">It gets better</a>:
<blockquote>Alex Armlovich: Texas SB840 is ending single-use commercial zoning, allowing apartments on top of habitable commercial uses statewide
This is by far the most muscular “Residential in Commercial Zoning” preemption bill I’ve ever seen
All the loopholes closed + a right of private action (!)
This bill is a bullseye painted on Dallas’s dogshit terrible zoning code & weak permitting process
Even after Austin’s recent reformist turn, I think this bill will have a measurable impact. And Houston too!
But Dallas is the biggest baddest NIMBY. And they got rolled <img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/B7duehMp2mSvffu2T/fwtbw8tuuhylggecsgrs" alt="😂" style="height:1em;max-height:1em"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/zSNLvRBhyphwuYdeC/ph06zv8tdg0m0yggnvdf" alt="👏" style="height:1em;max-height:1em">
YIMBYLAND: This law legalizes development & preempts cities over 150k from imposing
– Density limits below 36 unit/acre
– Heigh restrictions below 45ft
– Setbacks over 25ft
– Parking reqs over 1/unit</blockquote>
<h4>Poland</h4>
<a href="https://x.com/actsmaniac/status/1923072086630691016">Poland is the latest story of building more houses and housing costs going down</a>.
<blockquote>Acts Maniac: nobody in Europe is talking about the polish housing supply miracle.
The median household in polish cities (!) now only spends 13% of their income on housing.
They build about 200k units a year for a 36 million people country.
Michal Mynarski: why so? The difference of quantity and quality of shelter you can get for the same percentage of min/avg pay within last 15 years is outstanding. When I get to Wroclaw in 2011 usual price for a room was 2/3 min salary. Right now you can easily find a studio in that range.
<div>
<figure>
<div>
<figure class="wp-block-image"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wuoTsXoe93mXavofB/o0sv8qtcfjvizyg8s1ss" alt=""></figure>
<div></div>
</div>
</figure>
</div>
<div>
<figure>
<div>
<figure class="wp-block-image"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/wuoTsXoe93mXavofB/paceulg8srtldrpt36wk" alt=""></figure>
<div></div>
</div>
</figure>
</div>
</blockquote>
As usual note the y-axis starts around 12 on the first chart, but this is still a huge decline. The second chart is space per person.
 
<a href="https://www.lesswrong.com/posts/wuoTsXoe93mXavofB/housing-roundup-12#comments">Discuss</a>]]></description><link>https://www.lesswrong.com/posts/wuoTsXoe93mXavofB/housing-roundup-12</link><guid isPermaLink="false">wuoTsXoe93mXavofB</guid><dc:creator><![CDATA[Zvi]]></dc:creator><pubDate>Fri, 04 Jul 2025 12:10:02 GMT</pubDate></item><item><title><![CDATA[Can a pre-commitment to not give in to blackmail be "countered" by a pre-commitment to ignore such pre-commitments?]]></title><description><![CDATA[Published on July 4, 2025 11:48 AM GMT As I understand it an actor can prevent blackmail<a href="#fnfjs3e7tey">[1]</a> by (rational) actors it they credibly pre-commit to never give in to blackmail.Example: A newly elected mayor has many dark secrets and lots of people are already planning on blackmailing them. To preempt any such blackmail they livestreams themself being hypnotized and implanted with the suggestion to never give into blackmail. Since in this world hypnotic suggestions are unbreakable, all (rational) would-be blackmailers give up, since any attempt at blackmail would be guaranteed to fail.In general pre-commiting in such examples is about reducing the payoff matrix to just [blackmail, refuse] and [don't blackmail, refuse], which makes not blackmailing the optimal choice for the would-be blackmailer.Of course, sufficiently intelligent / coherent actors wouldn't need a external commitment mechanism and a sufficiently intelligent and informed opposition would be able to infer the existence of such a pre-commitment. More so, I believe to have heard that if a sufficiently  intelligent / coherent actors notices that it would be better of if it had pre-commited, it can just act as if it had (post-commit?).However, what if the would-be blackmailer also tries to limit the possible outcomes?Example: The anti-blackmail hypnosis is so successful that soon every newly elected mayor does it. A new candidate is likely to win the next election. They know that the local crime boss has a lot of dirt on them, but they aren't worried about blackmail, as they will just do the anti-blackmail hypnosis on their first day in office. On the evening of the election they are send a video of the crime boss being hypnotized into blackmailing the new mayor even if they have been anti-blackmail hypnotized.This cuts down the payoff matrix to [blackmail, refuse] and [blackmail, give in]. Giving in to the blackmail is optimal for the new mayor and doing the anti-blackmail hypnosis just locks them into [blackmail, refuse].So how does this work out between sufficiently intelligent / coherent actors? Does the first one to (credibly and transparently) pre-commit win?And what if actors are able to post-commit (if that even is a thing and I didn't misunderstand the concept)? A actor could act as if they had pre-commited to ignore the oppositions pre-commitment (to ignore pre-commitments to never give into blackmail), but then the opposition could act as if they had pre-commited to ignore that pre-commitment? (<a href="https://www.lesswrong.com/posts/Ljy3CSwTFPEpnGLLJ/the-blackmail-equation?commentId=mttG9oJbjHwnagTJT#mttG9oJbjHwnagTJT">This comment thread</a> seems to discuss the same question but did not resolve it for me.)<ol class="footnote-section footnotes" data-footnote-section="" role="doc-endnotes"><li class="footnote-item" data-footnote-item="" data-footnote-index="1" data-footnote-id="fjs3e7tey" role="doc-endnote" id="fnfjs3e7tey"><a href="#fnreffjs3e7tey">^</a><div class="footnote-content" data-footnote-content="">By blackmail I mean a scenario where the would-be blackmailers choices are blackmail or don't blackmail and the targets choices give in or refuse with a payoff matrix like this:<figure class="table"><table><thead><tr><th> </th><th>give in</th><th>refuse</th></tr></thead><tbody><tr><th>blackmail</th><td>target: -10 blackmailer: 20 </td><td>target: -100 blackmailer: -1</td></tr><tr><th>don't blackmail</th><td>target: 0 blackmailer: 0</td><td>target: 0 blackmailer: 0</td></tr></tbody></table></figure></div></li></ol> <a href="https://www.lesswrong.com/posts/FR3XWoCBTKADvPGjD/can-a-pre-commitment-to-not-give-in-to-blackmail-be#comments">Discuss</a>]]></description><link>https://www.lesswrong.com/posts/FR3XWoCBTKADvPGjD/can-a-pre-commitment-to-not-give-in-to-blackmail-be</link><guid isPermaLink="false">FR3XWoCBTKADvPGjD</guid><dc:creator><![CDATA[Sappique]]></dc:creator><pubDate>Fri, 04 Jul 2025 12:22:46 GMT</pubDate></item><item><title><![CDATA[Outlive: A Critical Review]]></title><description><![CDATA[Published on July 4, 2025 2:14 AM GMT <a href="https://peterattiamd.com/outlive/">Outlive: The Science & Art of Longevity</a> by Peter Attia (with Bill Gifford<a href="#fn-iPa8Phhvy9fzyWkHF-1" id="fnref-iPa8Phhvy9fzyWkHF-1">[1]</a>) gives Attia's prescription on how to live longer and stay healthy into old age. In this post, I critically review some of the book's scientific claims that stood out to me.
This is not a comprehensive review. I didn't review assertions that I was pretty sure were true (ex: <a href="https://en.wikipedia.org/wiki/VO2_max">VO2 max</a> improves longevity), or that were hard for me to evaluate (ex: the mechanics of how LDL cholesterol functions in the body), or that I didn't care about (ex: sleep deprivation impairs one's ability to identify facial expressions).
First, some general notes:
<ul>
<li>I have no expertise on any of the subjects in this post. I evaluated claims by doing shallow readings of relevant scientific literature, especially meta-analyses.</li>
<li>There is a spectrum between two ways of being wrong: "pop science book pushes a flashy attention-grabbing thesis with little regard for truth" to "careful truth-seeking author isn't infallible". Outlive makes it 75% of the way to the latter.</li>
<li>If I wrote a book that covered this many entirely different scientific fields, I would get a lot more things wrong than Outlive did. (I probably get a lot of things wrong in this post.)</li>
<li>When making my assessments, I give numeric credences and also use terms such as "true" and "likely true". The numbers give my all-things-considered subjective credences, and the qualitative terms give my interpretation of the strength of the empirical evidence. For example, if the scientific evidence suggests that a claim is 75% likely and I understand the evidence well, then I rate the claim as "likely true". If I only read the abstract of a single meta-analysis, and the abstract unequivocally supports the claim but I'm only 75% sure that the meta-analysis can be trusted, then I rate it as "true". Both claims receive a 75% credence.</li>
</ul>
Now let's have a look at some claims from Outlive, broken down into four categories: disease, exercise, nutrition, and sleep.
<h1>Disease</h1>
<h2>People with metabolically healthy obesity do not have elevated mortality risk</h2>
A person is defined as having <a href="https://en.wikipedia.org/wiki/Metabolic_syndrome">metabolic syndrome</a> if they show at least three out of five symptoms:
<ol>
<li>abdominal obesity (i.e. large waist circumference)</li>
<li>high blood pressure</li>
<li>high blood sugar</li>
<li>high serum triglycerides</li>
<li>low HDL cholesterol</li>
</ol>
People with obesity but no metabolic syndrome are said to have metabolically healthy obesity (MHO).
Here's what Outlive has to say about MHO:
<blockquote>
A large meta-analysis of studies with mean follow-up time of 11.5 years showed that people [with metabolic syndrome] have more than triple the risk of all-cause mortality and/or cardiovascular events than metabolically healthy normal-weight individuals. Meanwhile, the metabolically healthy but obese subjects in these studies were not at significantly increased risk. (page 95)<a href="#fn-iPa8Phhvy9fzyWkHF-2" id="fnref-iPa8Phhvy9fzyWkHF-2">[2]</a>
</blockquote>
My assessment:
<ul>
<li>The statement "MHO subjects in these studies were not at significantly increased mortality risk" is technically correct: true (credence: 90%<a href="#fn-iPa8Phhvy9fzyWkHF-3" id="fnref-iPa8Phhvy9fzyWkHF-3">[3]</a>).</li>
<li>Obesity has no negative health effects for metabolically healthy people: false (credence: 5%).</li>
<li>Metabolically healthy obesity does not increase mortality risk: highly unlikely (credence: 10%).</li>
</ul>
In support of its claim, the book cites <a href="https://doi.org/10.1016/j.cmet.2017.07.008">Stefan et al. (2017)</a><a href="#fn-iPa8Phhvy9fzyWkHF-4" id="fnref-iPa8Phhvy9fzyWkHF-4">[4]</a> which in turn cites <a href="/materials/kramer2013.pdf">Kramer et al. (2013)</a><a href="#fn-iPa8Phhvy9fzyWkHF-5" id="fnref-iPa8Phhvy9fzyWkHF-5">[5]</a>:
<blockquote>
In a pooled analysis of 8 studies, metabolically healthy obese persons had a similar risk for all-cause mortality or CV [cardiovascular] events compared with the metabolically healthy normal-weight individuals (RR, 1.19; [95%] CI, 0.98 to 1.38). [...] However, after we restricted analysis only to studies with at least 10 years of follow-up, the metabolically healthy obese group indeed had increased mortality and CV risk compared with the metabolically healthy normal-weight group (RR, 1.24; CI, 1.02 to 1.55; I^2 = 33.6%)
</blockquote>
Stefat et al. (2017) also found that MHO subjects had higher rates of chronic disease than metabolically healthy normal-weight subjects, see <a href="https://mdickens.me/assets/images/Stefan-2017-Figure-2.jpg">Figure 2</a>:
<img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/QqTiCz2Xz96MuEFsF/olxq4kaq7cert6dli0da" alt="">
"MHO does not increase risk" is one interpretation of this evidence. But I don't think it's a reasonable interpretation:
<ul>
<li>A <a href="https://en.wikipedia.org/wiki/Relative_risk">relative risk</a> (RR) of 1.19 sounds pretty bad. This finding is (just barely) not statistically significant, but it still has a likelihood ratio of about 5:1 compared to RR = 1<a href="#fn-iPa8Phhvy9fzyWkHF-6" id="fnref-iPa8Phhvy9fzyWkHF-6">[6]</a>—that is, we are 5x more likely to see this result if MHO elevates mortality risk by 1.19x than if it doesn't elevate risk at all.</li>
<li>MHO subjects had worse health across the board—higher rates of fatty liver disease, higher insulin resistance, lower cardiorespiratory fitness, more arterial plaque buildup—while also having non-significantly higher mortality. Which is a more reasonable interpretation: All those health problems somehow don't translate into increased mortality? Or the health problems do increase mortality, and the observed RR = 1.19 is real even though it's not statistically significant? (And the true RR probably isn't exactly 1.19, but it's somewhere in that vicinity.)</li>
</ul>
Many lament how often researchers treat p < 0.05 as "definitely real", but it bugs me just as much when they treat p > 0.05 as "definitely no effect".
Ben Carpenter at Red Pen Reviews <a href="https://www.redpenreviews.org/reviews/everything-fat-loss/">writes</a>:<a href="#fn-iPa8Phhvy9fzyWkHF-7" id="fnref-iPa8Phhvy9fzyWkHF-7">[7]</a>
<blockquote>
Roughly <a href="https://doi.org/10.1097%2FMD.0000000000008838">50% of people</a><a href="#fn-iPa8Phhvy9fzyWkHF-8" id="fnref-iPa8Phhvy9fzyWkHF-8">[8]</a> with metabolically healthy obesity will develop at least one metabolic abnormality within 3–10 years, which is double the risk of normal-weight individuals. Further, metabolically healthy obesity is still associated with an increased risk of <a href="https://doi.org/10.1177/2047487315623884">adverse cardiovascular events</a><a href="#fn-iPa8Phhvy9fzyWkHF-9" id="fnref-iPa8Phhvy9fzyWkHF-9">[9]</a>, <a href="https://doi.org/10.1016/j.atherosclerosis.2017.03.035">subclinical atherosclerosis</a><a href="#fn-iPa8Phhvy9fzyWkHF-10" id="fnref-iPa8Phhvy9fzyWkHF-10">[10]</a> (plaque buildup within the arterial walls), <a href="https://doi.org/10.1038/ajg.2016.178">nonalcoholic fatty liver disease</a><a href="#fn-iPa8Phhvy9fzyWkHF-11" id="fnref-iPa8Phhvy9fzyWkHF-11">[11]</a>, <a href="https://doi.org/10.1002/oby.22134">kidney function decline</a><a href="#fn-iPa8Phhvy9fzyWkHF-12" id="fnref-iPa8Phhvy9fzyWkHF-12">[12]</a>, and <a href="https://doi.org/10.1111/obr.12157">type II diabetes</a><a href="#fn-iPa8Phhvy9fzyWkHF-13" id="fnref-iPa8Phhvy9fzyWkHF-13">[13]</a>. So, considering this evidence, being metabolically healthy with obesity is probably short-lived and still has health risks.
</blockquote>
<h2>Amyloid beta is implicated in Alzheimer's disease</h2>
<blockquote>
[<a href="https://en.wikipedia.org/wiki/Amyloid_beta">Amyloid beta</a>] is clearly bad stuff. (page 181)
</blockquote>
My assessment: true (credence: 90%).
This claim stood out in my memory because a great deal of research on amyloid beta recently <a href="https://www.science.org/content/article/potential-fabrication-research-images-threatens-key-theory-alzheimers-disease">turned out to be fraudulent</a>. But upon re-reading the relevant section of Outlive, I found that none of the book's claims relied on the fraudulent research, and in fact the book cites the fraud investigation itself:
<blockquote>
[Some scientists'] doubts seemed to be validated in July of 2022, when Science published an article calling into question a widely cited 2006 study that had given new impetus to the amyloid theory, at a time when it had already seemed to be weakening.<a href="#fn-iPa8Phhvy9fzyWkHF-14" id="fnref-iPa8Phhvy9fzyWkHF-14">[14]</a> The 2006 study had pinpointed a particular subtype of amyloid that it claimed directly caused neurodegeneration. That in turn inspired numerous investigations into the subtype. But according to the Science article, key images in that study had been falsified. (page 183–184)
</blockquote>
The claims made in Outlive about the apparent negative effects of amyloid beta come from studies that predate the 2006 fraud, and those older claims appear to hold up. The book accurately describes the current state of the field as far as I understand it: amyloid beta is associated with at least some cases of Alzheimer's, but research into amyloid beta has so far failed to uncover any useful treatments.
<h2>HDL cholesterol on its own doesn't prevent heart disease</h2>
I wrote this claim in my notes on my first read-through, but upon re-reading, Outlive never actually said this. I'm including this claim anyway so that readers know I have poor reading comprehension and can't be trusted.<a href="#fn-iPa8Phhvy9fzyWkHF-15" id="fnref-iPa8Phhvy9fzyWkHF-15">[15]</a>
Here's what the book actually said:
<blockquote>
Risk does seem to decline as HDL-C rises to around the 80th percentile. But simply raising HDL cholesterol concentrations by brute force, which specialized drugs, has not been shown to reduce cardiovascular risk at all. (page 123)
</blockquote>
My assessment:
<ul>
<li>HDL cholesterol on its own doesn't prevent heart disease: false, but Outlive never said that—in fact, it said the opposite.</li>
</ul>
<h1>Exercise</h1>
The book (rightly) focuses more on exercise than on nutrition or sleep. <s>From what I can tell, it is the most scientifically accurate section of the book.</s>
Update 2025-05-05: I've come to learn more about exercise and longevity, and I now believe some of Outlive's claims on exercise are incorrect or overstated. The next three sections below explain my updated beliefs. They largely cover the same ground as my recent post, <a href="https://mdickens.me/2025/02/03/I_was_probably_wrong_about_HIIT_and_VO2max/">I was probably wrong about HIIT and VO2max</a>, but with better evidence and citations (citing meta-analyses instead of tweets).
<h2>VO2max is the best predictor of longevity</h2>
Outlive never directly says VO2max is the best predictor of longevity, but it sure implies it. The book spends eight pages talking about the association between VO2max and longevity, and about how important it is.
My assessment:
<ul>
<li>Increasing VO2max increases longevity: true (credence: 97%).</li>
<li>The causal relationship between VO2max and longevity is as strong as Outlive implies: false (credence: 10%).</li>
<li>VO2max is the best proxy for physical fitness: false (credence: 20%) – performance on fitness tests (e.g. maximum pace on an incline treadmill) is easier to measure and probably more accurate.<a href="#fn-iPa8Phhvy9fzyWkHF-16" id="fnref-iPa8Phhvy9fzyWkHF-16">[16]</a></li>
</ul>
I have two objections to how Outlive characterizes VO2max:
<ol>
<li>The book cites observational studies, not RCTs.</li>
<li>VO2max is a proxy for physical fitness, not physical fitness itself. And there are better proxies.</li>
</ol>
Correlation is not causation. I am confident that training to increase VO2max does, in fact, increase longevity. But I believe observational studies overstate the magnitude of the effect.
I've looked at both observational studies and RCTs on the relationship between exercise and health, and my sense is that observational studies overstate the causal effect by about 2x. (It's on my to-do list to write a post about why I believe this.) I don't know about VO2max in particular, but I expect that only about half of its observed association with longevity is causal.
However, even after cutting the effect in half, exercise is still the best general-purpose<a href="#fn-iPa8Phhvy9fzyWkHF-17" id="fnref-iPa8Phhvy9fzyWkHF-17">[17]</a> intervention for longevity.
As for my second objection: VO2max is only a proxy for physical fitness. Here I will quote an <a href="https://thegrowtheq.com/longevity-and-vo2max-does-it-matter/">article</a> by elite running coach Steve Magness, because I can't explain it any better than he did:
<blockquote>
In practical terms, Vo2max is like knowing the size of a car’s engine, which is really important if we want to know about performance. But if we want to know whether that car has a chance to win the Daytona 500, engine size alone won’t tell us. We also need to to know about the size of the fuel tank, about its fuel economy, about how long its tires will hold up, and about all the other small components that translate the power of engine to the speed of the car. It’s the same in humans. Vo2max is one of many components that, taken together, tell us about our holistic aerobic or cardiorespiratory fitness.
[...]
Vo2max matters. But it’s just one component of many that make up both performance and aerobic fitness. And that’s important because if we return to the original claims that Vo2max is the key indicator of longevity, we’ll find that the majority of the studies cited did NOT even use Vo2max as the main variable. They used performance! In the majority of research, peak speed and incline during the [Vo2max] test was the main correlate to longevity.
The large <a href="https://www.sciencedirect.com/science/article/pii/S0735109722052603#bib36">study</a><a href="#fn-iPa8Phhvy9fzyWkHF-18" id="fnref-iPa8Phhvy9fzyWkHF-18">[18]</a> on 750,000 veterans that found a 4-fold higher mortality risk for low versus high fitness used peak speed and incline, not Vo2max. Same with the <a href="https://jamanetwork.com/journals/jamanetworkopen/article-abstract/2707428">research</a><a href="#fn-iPa8Phhvy9fzyWkHF-19" id="fnref-iPa8Phhvy9fzyWkHF-19">[19]</a> on 120,000 individuals finding a 5x difference in the risk of early death.
[...] And as we can see in this <a href="https://www.sciencedirect.com/science/article/abs/pii/S0033062017300439">meta-analysis</a><a href="#fn-iPa8Phhvy9fzyWkHF-20" id="fnref-iPa8Phhvy9fzyWkHF-20">[20]</a> looking at mortality and fitness, all but a handful of the included studies used an estimate based on speed or time.
You get the point.
And this is good news! It means you don’t need to go to a lab and measure your Vo2max. You don’t even need to worry about Vo2max itself (or your watche’s [sic] horrible estimation of it). All you need to do is focus on overall aerobic fitness. Which can easily be measured, compared, and improved in a number of ways that are less expensive and more accessible than Vo2max.
</blockquote>
So, in short: most studies that measure "VO2max" are actually measuring performance on a fitness test. And this is good news, because it means if your performance is improving—if your mile time or your 5K time is getting faster—then you're making real progress.
<h2>You should train VO2max by doing HIIT at the maximum sustainable pace</h2>
Outlive recommends doing high-intensity interval training (<a href="https://en.wikipedia.org/wiki/High-intensity_interval_training">HIIT</a>) to improve VO2max:
<blockquote>
The tried-and-true formula for [VO2max training] is to go four minutes at the maximum pace you can sustain for this amount of time—not an all-out sprint, but still a very hard effort. Then ride or jog four minutes easy, which should be enough time for your heart rate to come back down to below about one hundred beats per minute. Repeat this four to six times and cool down. (page 249)
</blockquote>
My assessment:
<ul>
<li>The best exercise routine includes HIIT: likely true (credence: 85%).</li>
<li>Longer intervals are better than shorter intervals: likely true (credence: 85%).</li>
<li>HIIT should be done at the maximum sustainable pace: false (credence: 25%).</li>
<li>HIIT is the best way to improve VO2max: likely true (credence: 70%).</li>
</ul>
Four-minute intervals are reasonable: a meta-analysis by <a href="/website/materials/wen2019.pdf">Wen et al. (2019)</a><a href="#fn-iPa8Phhvy9fzyWkHF-21" id="fnref-iPa8Phhvy9fzyWkHF-21">[21]</a> found that ≥2-minute intervals produced bigger performance benefits than <2 minutes (although all interval durations improved VO2max).
But I have two concerns:
<ol>
<li>Training at the maximum sustainable pace is a recipe for burnout. You should train at a pace that's difficult, but not maximum effort.</li>
<li>There is mixed evidence on whether HIIT is the best way to improve VO2max. Low-intensity training might be just as good.</li>
</ol>
For the first concern:
Taken literally, the quoted prescription is impossible to follow. If you do your first interval at the maximum sustainable pace, then your second interval cannot possibly be done at the same pace because you will be fatigued from the first interval.
Perhaps Attia meant to say that you should go at the maximum pace you can sustain across all intervals. That's physically possible, but it still seems like a bad idea.
I wanted to cite RCT evidence comparing HIIT at different intensities while controlling for duration (e.g., 4-minute intervals at maximum pace vs. 4-minute intervals at 90% of maximum pace). But I couldn't find any. Instead, the evidence on this question comes from studies of how athletes train.
Elite athletes typically do HIIT at roughly 90% of VO2max (<a href="/materials/seiler2010">Seiler (2010)</a><a href="#fn-iPa8Phhvy9fzyWkHF-22" id="fnref-iPa8Phhvy9fzyWkHF-22">[22]</a>). This is considerably slower than the maximum sustainable pace (<a href="/materials/billat2001.pdf">Billat (2001)</a><a href="#fn-iPa8Phhvy9fzyWkHF-23" id="fnref-iPa8Phhvy9fzyWkHF-23">[23]</a>). For example, <a href="https://doi.org/10.3109/13813459508996126">Billat et al. (1995)</a><a href="#fn-iPa8Phhvy9fzyWkHF-24" id="fnref-iPa8Phhvy9fzyWkHF-24">[24]</a> found that a sample of elite long-distance runners could maintain 90% of VO2max for an average of 16.55 minutes.<a href="#fn-iPa8Phhvy9fzyWkHF-25" id="fnref-iPa8Phhvy9fzyWkHF-25">[25]</a> If you can maintain a certain pace for 16 minutes straight, then you can certainly run at that pace for four 4-minute intervals with rests in between.
For the second concern: is HIIT really better than low-intensity training (LIT)<a href="#fn-iPa8Phhvy9fzyWkHF-26" id="fnref-iPa8Phhvy9fzyWkHF-26">[26]</a> for improving VO2max? Probably yes, but it's unclear.
The RCT evidence on this is mixed. A meta-analysis by <a href="/website/materials/wen2019.pdf">Wen et al. (2019)</a><a href="#fn-iPa8Phhvy9fzyWkHF-21" id="fnref-iPa8Phhvy9fzyWkHF-21:1">[21:1]</a> found that HIIT worked better than LIT for increasing VO2max. However, a review of meta-analyses by <a href="https://doi.org/10.1155/2022/9310710">Crowley et al. (2022)</a><a href="#fn-iPa8Phhvy9fzyWkHF-27" id="fnref-iPa8Phhvy9fzyWkHF-27">[27]</a> found inconsistent evidence.<a href="#fn-iPa8Phhvy9fzyWkHF-28" id="fnref-iPa8Phhvy9fzyWkHF-28">[28]</a>
I didn't look at most of the meta-analyses reviewed by Crowley et al. I did look at <a href="https://doi.org/10.1007/s40279-013-0115-0">Gist et al. (2013)</a>, which at a glance appears to be the most rigorous "contrarian" meta-analysis. It found that sprint interval training did not increase VO2max by more than endurance training. However, this is roughly consistent with <a href="/website/materials/wen2019.pdf">Wen et al. (2019)</a><a href="#fn-iPa8Phhvy9fzyWkHF-21" id="fnref-iPa8Phhvy9fzyWkHF-21:2">[21:2]</a>, which found that longer intervals (2+ minutes) worked better than sprint intervals.
RCTs may overstate the benefits of HIIT relative to LIT. A meta-analysis by <a href="https://doi.org/10.1007/s40279-024-02120-2">Mølmen et al. (2024)</a><a href="#fn-iPa8Phhvy9fzyWkHF-29" id="fnref-iPa8Phhvy9fzyWkHF-29">[29]</a> found that HIIT rapidly improved participants' fitness, whereas the benefits of LIT took longer to show up. Therefore, a 5-week study will show a clear advantage to HIIT even if LIT might be better in the long run:
<img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/QqTiCz2Xz96MuEFsF/mlm4i4mmeey7idgr9haf" alt="">
(ET = endurance training; HIT = high-intensity training; SIT = sprint-intensity training)
That being said, there is some evidence that HIIT provides benefits on top of LIT, so if your goal is to optimize longevity, then I believe it makes sense to do both.
<h2>You should do 3+ hours/week of zone 2 training and one or two sessions/week of HIIT</h2>
<blockquote>
[I]t seems that about three hours per week of zone 2, or four 45-minute sessions, is the minimum required for most people to derive a benefit and make improvements, once you get over the initial hump of trying it for the first time. (page 243)
</blockquote>
<blockquote>
Even if we are not out to set world records, the way we train VO2max is pretty similar to the way elite athletes do it: by supplementing our zone 2 work with one or two VO2max workouts per week. (page 249)
</blockquote>
My assessment:
<ul>
<li>This is a good exercise routine: true (credence: 95%).</li>
<li>This routine is uniquely better than any other: likely false (credence: 25%).</li>
</ul>
RCT evidence doesn't tell us much about the optimal exercise routine. As with HIIT vs. LIT, the best evidence comes from looking at how top athletes train.
Elite athletes typically do 80% of their training at low/moderate intensity (a.k.a. <a href="https://trainright.com/zone-2-training-to-improve-aerobic-endurance-and-fat-burning/">zone 2</a>), and 20% at high intensity (<a href="/materials/seiler2010">Seiler (2010)</a><a href="#fn-iPa8Phhvy9fzyWkHF-22" id="fnref-iPa8Phhvy9fzyWkHF-22:1">[22:1]</a>; <a href="https://doi.org/10.3389/fphys.2015.00295">Stöggl & Sperlich (2015)</a><a href="#fn-iPa8Phhvy9fzyWkHF-30" id="fnref-iPa8Phhvy9fzyWkHF-30">[30]</a>). For elite athletes, doing more than 20% of cardio sessions at high intensity can induce overtraining (<a href="/materials/seiler2010">Seiler (2010)</a><a href="#fn-iPa8Phhvy9fzyWkHF-22" id="fnref-iPa8Phhvy9fzyWkHF-22:2">[22:2]</a>).
Outlive recommends training at just two intensities: low and high. But many elite athletes train at three or more different durations/intensities (<a href="https://doi.org/10.3389/fphys.2015.00295">Stöggl & Sperlich (2015)</a><a href="#fn-iPa8Phhvy9fzyWkHF-30" id="fnref-iPa8Phhvy9fzyWkHF-30:1">[30:1]</a>). Different training modalities cause your body to adapt in different ways, so it makes sense to mix things up. You might do something like 80% zone 2 training, 15% long-duration (~4-minute) interval training, 5% sprint (< 1 minute) interval training. But just two intensities is probably sufficient to get the vast majority of longevity benefits.
I am not confident that ordinary folks should follow the same 80/20 rule as elite athletes. Professionals train 20–30 hours per week, including 4+ hours of high-intensity training. If I do 5 hours a week of cardio instead of 20, do I really need to restrict my HIIT to only one hour? Maybe I could handle 2 or 3 hours (or even 5 hours) without overtraining. But in the absence of direct evidence, I'll follow the 80/20 rule.
For the record, my exercise routine is:
<ul>
<li>Low-intensity cardio 3x/week for 45 to 90 minutes (depending on how I'm feeling);</li>
<li>HIIT once every 1–2 weeks (usually four 4-minute intervals, and occasionally a different variation);</li>
<li>Resistance training 3-4x/week.</li>
</ul>
I think this is less than the optimal amount of HIIT, but I don't like doing HIIT.
<h2>Stability is as important as cardiovascular fitness and strength</h2>
Outlive claims that exercise is the best way to increase longevity, and that the ideal exercise programs includes four components:
<ol>
<li>long-duration, low-intensity cardio ("zone 2" training)</li>
<li>high-intensity interval training (VO2 max training)</li>
<li>strength training</li>
<li>stability training</li>
</ol>
An abundance of evidence shows that the first three types of exercise are excellent for health and longevity. The fourth is not so well-supported.
<blockquote>
[Stability] is the foundation on which our twin pillars of cardiovascular fitness and strength must rest. (page 265)
</blockquote>
My assessment: I don't know how to evaluate this. It seems to border on <a href="https://en.wikipedia.org/wiki/Not_even_wrong">not even wrong</a>.
The book defines stability as "the subconscious ability to harness, decelerate, or stop force", while admitting that this isn't a great definition. I don't know how to empirically test stability by this definition. You can formally define cardiovascular fitness as VO2 max (or resting heart rate, etc.), and then show that improving your chosen metric improves health and reduces mortality risk. But I don't know how to operationalize "stability".
(On one reading, this definition of stability sounds nearly identical to "strength", because your ability to decelerate/stop force is pretty much entirely determined by your ability to generate force.)
The chapter on stability only made two-ish testable claims that I could identify. The first:
<blockquote>
DNS [dynamic neuromuscular stabilization] originated with a group of Czech neurologists who were working with young children with cerebral palsy in a hospital in Prague in the 1960s. They noticed that because of their illness, these kids did not go through the normal infant stages of rolling, crawling, and so forth. Thus they had movement problems throughout their lives. But when the children with cerebral palsy were put through a "training" program consisting of a certain sequence of movements, replicating the usual stages of learning to crawl, sit up, and eventually stand, their symptoms improved and they were better able to control their motions as they matured. The researchers realized that as we grow up, most healthy humans actually go through an opposite process—we lose these natural, healthy, almost ingrained movements. (page 270)
</blockquote>
(The book cites <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3578435/">Frank et al. (2013)</a><a href="#fn-iPa8Phhvy9fzyWkHF-31" id="fnref-iPa8Phhvy9fzyWkHF-31">[31]</a>.)
TLDR: Some research found that DNS helped children with cerebral palsy, so it might also help adults prevent injuries. The assertion that it would help adults is presented without evidence, and to my knowledge, no evidence exists.
Relatedly, Outlive cites an <a href="https://peterattiamd.com/michaelrintala/">interview</a> Peter Attia did with "leading American practitioner of DNS" Michael Rintala, D.C. (a.k.a. Doctor of Chiropractic). <a href="https://en.wikipedia.org/wiki/Chiropractic">Chiropractic</a> is pseudoscience and chiropractors are fake doctors, so without having looked into this much, I'm pretty skeptical of DNS. If Rintala practices bogus medicine in one arena, that's evidence that his DNS research is also bogus.
I don't know that this first claim is false, but it's essentially pulled out of thin air so I have no reason to believe that it's true.
Outlive makes a second semi-testable claim: it implies (but does not explicitly state) that squatting with perfect form has lower injury risk than squatting asymmetrically. This claim sounds intuitively plausible but I could not find any supporting evidence (and there's some evidence that "bad" squat form isn't necessarily bad<a href="#fn-iPa8Phhvy9fzyWkHF-32" id="fnref-iPa8Phhvy9fzyWkHF-32">[32]</a>).
And squatting asymmetrically is probably better than not squatting at all (credence: 90%) because (1) studies find robust health benefits to strength training and (2) probably most of the subjects in those studies don't have particularly good form.
Outlive didn't do a good job of defining "stability training", so I'll do it myself. Let's say the purpose of stability training is to reduce the risk of falling. In that case, is stability training useful?
<ul>
<li>A meta-analysis by <a href="https://doi.org/10.1071/NB10056">Sherrington et al. (2011)</a><a href="#fn-iPa8Phhvy9fzyWkHF-33" id="fnref-iPa8Phhvy9fzyWkHF-33">[33]</a> found that essentially any kind of exercise reduced fall risk, with balance training having a 22% larger effect than an "average" exercise program, and long-duration exercise (>50 hour trial duration) having a 23% larger effect than "average". So "stability training" does appear to work, and high-dose exercise programs that included balance training reduced fall risk by 38%.</li>
<li>A meta-analysis by <a href="https://doi.org/10.1001/jamainternmed.2018.5406">de Souto Barreto et al. (2019)</a><a href="#fn-iPa8Phhvy9fzyWkHF-34" id="fnref-iPa8Phhvy9fzyWkHF-34">[34]</a> found that exercise significantly reduced falls (RR = 0.88) and injurious falls (RR = 0.74), and non-significantly reduced fractures (RR = 0.84, 95% CI 0.71–1.00). It compared exercise programs by type: (1) aerobic, (2) strength, (3) other (tai chi/dance), (4) multicomponent (aerobic + strength + balance). The meta-analysis did not find any significant differences between four types. (And it wasn't a p = 0.06 situation either—most of the p-values were greater than 0.8.)</li>
<li>There's some contrary evidence on balance training. A meta-analysis by <a href="https://link.springer.com/article/10.1007/s40279-016-0515-z">Kümmel et al. (2016)</a><a href="#fn-iPa8Phhvy9fzyWkHF-35" id="fnref-iPa8Phhvy9fzyWkHF-35">[35]</a> found that balance training on a particular task improves performance on that task, but does not transfer even to very similar tasks. This gives reason to doubt that balance training reduces injury risk.</li>
</ul>
So exercise appears to help with stability. And balance exercises might work better than other types of exercise, but they might not work at all.
My assessment of some claims that Outlive didn't make, but sort of implied:
<ul>
<li>Stability is useful: likely true (credence: 90%).</li>
<li>Exercise can improve stability: likely true (credence: 80%).</li>
<li>Exercising to improve stability matters as much as exercising to reduce cardiovascular disease/diabetes/cancer: almost certainly false (credence: 5%).</li>
<li>Most people should do additional stability training on top of the cardio and strength training that they should already be doing: likely false (credence: 15%).</li>
</ul>
<h1>Nutrition</h1>
<h2>Rhesus monkey studies suggest that calorie restriction improves longevity but only if you eat a fairly unhealthy diet</h2>
I won't provide a direct quote from Outlive because it would be too long. To summarize, the book says (pages 312–316):
<ul>
<li>A 2009 University of Wisconsin-Madison (UW) <a href="https://doi.org/10.1126/science.1173635">study</a><a href="#fn-iPa8Phhvy9fzyWkHF-36" id="fnref-iPa8Phhvy9fzyWkHF-36">[36]</a> found that rhesus monkeys on a calorie-restricted diet lived longer than the control group.</li>
<li>But a similar 2012 <a href="(https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3832985/)">study</a><a href="#fn-iPa8Phhvy9fzyWkHF-37" id="fnref-iPa8Phhvy9fzyWkHF-37">[37]</a> by the National Institute of Aging (NIA) found that a calorie-restricted diet did not improve longevity.</li>
<li>The biggest difference between the studies was that the UW monkeys ate processed food and the NIA monkeys ate a whole-foods diet formulated by a primate nutritionist.</li>
<li>So it looks like calorie restriction improves longevity if you eat mostly processed food, and doesn't matter much if you eat a healthy diet.</li>
</ul>
My assessment:
<ul>
<li>Outlive accurately summarizes these two studies: true (credence: 90%).</li>
<li>Calorie restriction (CR) improves longevity but only if you eat a fairly unhealthy diet: likely true (credence: 70%).</li>
<li>The rhesus monkey studies support the above claim: unclear (credence: 50%).</li>
<li>The rhesus monkey studies generalize well to humans: somewhat unlikely (credence: 35%).</li>
</ul>
I found the book's interpretation to be reasonable and appropriately couched in uncertainty but I want to write about the studies because they were interesting.
A 2017 <a href="https://doi.org/10.1038/ncomms14063">collaboration</a><a href="#fn-iPa8Phhvy9fzyWkHF-38" id="fnref-iPa8Phhvy9fzyWkHF-38">[38]</a> by the authors of the UW and NIA studies reviewed the differences in study designs and outcomes. They agreed with Attia's interpretation that diet quality was the most likely explanation for the different results, and that the studies jointly suggest that calorie intake is an important predictor of longevity—the monkeys in the NIA control group ate as little as those in the UW calorie restriction (CR) group.
I read the collaboration and noticed some results that don't add up:
<ul>
<li>In the NIA study, the control group developed more chronic disease than the CR group (<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5247583/figure/f6/">Figure 6</a>), which seemingly contradicts the finding that calorie restriction didn't help.</li>
<li>NIA split monkeys into young and old cohorts based on the age of each monkey when the study started. Within the young cohort, the CR group had less chronic disease (<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5247583/figure/f6/">Figure 6</a>), but had worse mean and median longevity (<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5247583/table/t3/?report=objectonly">Table 2</a>). Why do these two measurements point in opposite directions?
<ul>
<li>CR reduced lifespan in the young NIA cohort, and the magnitude of the effect was larger than in the UW study, but it wasn't statistically significant<a href="#fn-iPa8Phhvy9fzyWkHF-39" id="fnref-iPa8Phhvy9fzyWkHF-39">[39]</a> so of course the authors ignored it. I'm not saying it's a real effect, I'm just saying if you get a result (even a non-significant result) that goes in the opposite direction of what you predicted, then you should take that as a cue that you're missing something.<a href="#fn-iPa8Phhvy9fzyWkHF-40" id="fnref-iPa8Phhvy9fzyWkHF-40">[40]</a></li>
</ul>
</li>
<li>The NIA young male cohort saw a decrease in <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5247583/figure/f2/">bodyweight</a> and <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5247583/figure/f3/">body fat</a> while the other three NIA cohorts saw essentially no change. Presumably, the main mechanism of calorie restriction is that it prevents obesity, so we should see a longevity improvement among NIA young males and not among the other three cohorts. But that's not what we see. Instead we see essentially no effect in old males/females and a negative effect in young males/females.</li>
<li>In the NIA study, why did calorie restriction reduce average bodyweight for males but not for females (<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5247583/figure/f2/">Figure 2</a>)? The authors took this as evidence of "sexual dimorphism in the relationship between food intake and bodyweight". That does not sound plausible to me.</li>
<li>According to the authors: "In rodents, early onset CR is more effective in extending longevity than adult onset CR. For nonhuman primates it appears that CR, while beneficial when implemented in adulthood, does not improve survival when implemented in juveniles." It's suspicious that rodent studies and monkey studies produced opposite results in this respect.</li>
</ul>
The NIA control group monkeys ate about as much as the UW calorie-restricted monkeys, which the authors take as evidence in favor of the original hypothesis—lower caloric intake improves longevity. Maybe.<a href="#fn-iPa8Phhvy9fzyWkHF-41" id="fnref-iPa8Phhvy9fzyWkHF-41">[41]</a> Or maybe it was the higher-quality diet (irrespective of caloric intake), or some other difference between the two studies.<a href="#fn-iPa8Phhvy9fzyWkHF-42" id="fnref-iPa8Phhvy9fzyWkHF-42">[42]</a>
If two studies conflict, I'm wary of making my hypothesis more complicated to fit the results. The hypothesis started as "CR improves longevity", which the UW study supported. But when the NIA study produced contradictory evidence, the hypothesis became "CR improves longevity, unless you're eating a healthy diet, in which case it doesn't".
The two studies together support this hypothesis, but they don't distinguish it from other plausible hypotheses (see previous footnote, repeated here<a href="#fn-iPa8Phhvy9fzyWkHF-42" id="fnref-iPa8Phhvy9fzyWkHF-42:1">[42:1]</a>).
And if you look closely at the NIA results, the hypothesis needs to become even more complicated: something like "CR improves longevity, but if you're eating a healthy diet then it has no effect for old monkeys and a harmful effect for young monkeys, and the mechanism is presumably that monkeys with healthy diets tend to have lower rates of obesity, except that young males in the NIA study didn't weigh much less than in UW so for young males the mechanism is some other thing, and also the young vs. old effect is reversed in rodents for some reason."
The more complicated a hypothesis, the more supporting evidence it requires.
More broadly, I'm skeptical that CR studies on lab animals generalize to the real world. Peter Attia agrees:
<blockquote>
CR's usefulness remains doubtful outside the lab; very lean animals may be more susceptible to death from infection or cold temperatures. [...] Furthermore, there is no evidence that extreme CR would truly maximize the longevity function in an organism as complex as we humans, who live in a more variable environment than the animals [studied]. While it seems likely that it would reduce the risk of succumbing to at least some [chronic diseases], it seems equally likely that the uptick in mortality due to infections, trauma, and frailty might offset these gains. (page 81)
</blockquote>
Another fact that seems important to me, but that Attia and the UW/NIA authors didn't discuss: the monkeys never exercised. They were permanently housed in small cages (<a href="https://doi.org/10.1016/j.neurobiolaging.2004.09.013">Mattison et al. (2005)</a><a href="#fn-iPa8Phhvy9fzyWkHF-43" id="fnref-iPa8Phhvy9fzyWkHF-43">[43]</a>). Some of the the UW monkeys did participate in a different <a href="https://doi.org/10.1016/j.exger.2013.08.002">study</a><a href="#fn-iPa8Phhvy9fzyWkHF-44" id="fnref-iPa8Phhvy9fzyWkHF-44">[44]</a> measuring their physical activity which moved them to a metabolic chamber, but the metabolic chamber was about the same size as the cages—i.e., too small for meaningful exercise.
Physical activity appears to largely or fully cancel out the harms of higher-calorie diets.<a href="#fn-iPa8Phhvy9fzyWkHF-45" id="fnref-iPa8Phhvy9fzyWkHF-45">[45]</a> Even if calorie restriction works for sedentary people, it's less likely to improve health for folks who exercise regularly.
Returning to the original hypothesis—"CR improves longevity but only if you eat a fairly unhealthy diet"—these studies provide a small amount of evidence for the hypothesis but not much. That said, the hypothesis sounds correct to me:
<ul>
<li>People with unhealthy diets tend to overeat, so eating less would probably improve their health.</li>
<li>People who get most of their calories from healthy sources (whole grains, nuts, etc.) are much less likely to overeat, so there's no point in calorie restriction.</li>
</ul>
<h2>The data are unclear on whether reducing saturated fat intake is beneficial</h2>
(Note: SFA = saturated fatty acid, MUFA = monounsaturated fatty acid, PUFA = polyunsaturated fatty acid)
<blockquote>
A more recent publication by the Cochrane Collaboration, published in 2020 as a 287-page treatise titled Reduction in Saturated Fat Intake for Cardiovascular Disease<a href="#fn-iPa8Phhvy9fzyWkHF-46" id="fnref-iPa8Phhvy9fzyWkHF-46">[46]</a>, looked at fifteen RCTs in over fifty-six thousand patients and found, among other things, that "reducing dietary saturated fat reduced the risk of combined cardiovascular events by 17%." Interesting. But the same review also found "little or no effect of reducing saturated fat on all-cause mortality or cardiovascular mortality."
[...]
The data are very unclear on this question, at least at the population level. [...] [A]ny hope of using broad insights from evidence-based medicine is bound to fail when it comes to nutrition, because such population-level data cannot provide much value at the individual level when the effect sizes are so small, as they clearly are here. (pages 337–338)
</blockquote>
And a bonus quote:
<blockquote>
If, after reading this chapter, you’re upset because you don’t quite agree with some detail I’ve covered—be it the ratio of MUFA to PUFA to SFA, or the exact bioavailability of soy protein, the role of seed oils and lectins, or the ideal target for average blood glucose levels [...], I have one final piece of advice. Stop overthinking nutrition so much. Put the book down. Go outside and exercise. (page 346)
</blockquote>
Well joke’s on you, I already exercised today, and now I’m back to over-analyze saturated fat.
My assessment:
<ul>
<li>Saturated fat is unhealthy in expectation: likely true (credence: 85%).</li>
<li>It's a good idea for most people to reduce their SFA intake: possible (credence: 50%).<a href="#fn-iPa8Phhvy9fzyWkHF-47" id="fnref-iPa8Phhvy9fzyWkHF-47">[47]</a></li>
<li>It's a good idea for people with high cholesterol to reduce their SFA intake: likely true (credence: 70%).</li>
<li>The data are unclear: unclear. (Yes, it's unclear whether the data are unclear. It depends on how much clarity you want.)</li>
<li>The amount of SFA in your diet doesn't matter all that much: possible (credence: 50%).</li>
</ul>
Attia's position on saturated fat stuck out to me because the mainstream view says saturated fat is unhealthy. After spending much longer on this than I'd originally planned, I've come to the conclusion that the mainstream advice is basically reasonable, and Attia's position is also basically reasonable. There's some evidence that reducing SFA is beneficial and there's little evidence to the contrary, but (a) the evidence is only moderately strong at best, and (b) there's a lot of variation in how SFA affects people, so you might not need to worry about it unless you have high cholesterol.
Observational studies have found mixed results, with the more reliable studies generally finding moderate associations between saturated fat and heart disease. For example, <a href="https://doi.org/10.1136/bmj.i5796">Zong et al. (2016)</a><a href="#fn-iPa8Phhvy9fzyWkHF-48" id="fnref-iPa8Phhvy9fzyWkHF-48">[48]</a> found that shifting 1% of daily calories from saturated fat to polyunsaturated fat was associated with an 8% reduction in coronary heart disease (p < 0.001). But observational studies don't establish causality, so let's look at randomized controlled trials (RCTs).
A 2020 <a href="https://doi.org/10.1002/14651858.cd011737.pub3">Cochrane review</a><a href="#fn-iPa8Phhvy9fzyWkHF-46" id="fnref-iPa8Phhvy9fzyWkHF-46:1">[46:1]</a> of RCTs found that replacing dietary saturated fat significantly reduced cardiovascular events and LDL cholesterol levels, and non-significantly reduced all-cause mortality and cardiovascular mortality. (Some other meta-analyses of RCTs have been done,<a href="#fn-iPa8Phhvy9fzyWkHF-49" id="fnref-iPa8Phhvy9fzyWkHF-49">[49]</a> but the Cochrane review likely has the strongest methodology.)
It's not entirely clear how to interpret the results of the Cochrane review. Out of eight <a href="https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD011737.pub3/full#CD011737-sec-0008">primary outcome variables</a> (including all-cause mortality, cardiovascular mortality, etc.), reducing SFA only statistically significantly improved one variable. But it showed a positive effect for all eight. This weakly suggests that there's a real effect and the RCTs were underpowered for most of the measures. If we treated the eight measures as independent, this would constitute strong evidence of a real effect, but the measures are mostly correlated with each other.
The Cochrane review looked at dozens of other outcome variables. Most importantly, replacing saturated fat significantly reduced LDL cholesterol. (A <a href="https://iris.who.int/bitstream/handle/10665/246104/9789241565349-eng.pdf">WHO (2016)</a><a href="#fn-iPa8Phhvy9fzyWkHF-50" id="fnref-iPa8Phhvy9fzyWkHF-50">[50]</a> meta-analysis of 84 RCTs agreed with this result.) Cholesterol-lowering drugs have been shown to lower all-cause mortality (see <a href="https://doi.org/10.1001/jama.2018.2525">Navarese et al. (2018)</a><a href="#fn-iPa8Phhvy9fzyWkHF-51" id="fnref-iPa8Phhvy9fzyWkHF-51">[51]</a> and <a href="https://doi.org/10.1097/fjc.0000000000001345">Ennezat et al. (2022)</a><a href="#fn-iPa8Phhvy9fzyWkHF-52" id="fnref-iPa8Phhvy9fzyWkHF-52">[52]</a>), so it stands to reason—although we only have weak direct evidence—that if reducing SFA improves LDL cholesterol, then it should improve all-cause mortality. Somewhat contradicting this, an RCT by <a href="https://doi.org/10.1093/ajcn/nqz035">Bergeron et al. (2019)</a><a href="#fn-iPa8Phhvy9fzyWkHF-53" id="fnref-iPa8Phhvy9fzyWkHF-53">[53]</a> found that SFA caused the body to produce mainly larger LDL particles, which are less harmful than small particles.
<a href="https://www.ahajournals.org/doi/full/10.1161/CIR.0000000000000510">Sacks et al. (2017)</a><a href="#fn-iPa8Phhvy9fzyWkHF-54" id="fnref-iPa8Phhvy9fzyWkHF-54">[54]</a> performed a review with stricter inclusion criteria, looking only at RCTs that:
<ul>
<li>controlled subjects' dietary intake;</li>
<li>lasted at least 2 years;</li>
<li>proved adherence by measuring biomarkers like cholesterol;</li>
<li>did not replace saturated fats with trans fats in the intervention group.</li>
</ul>
Only four trials met these criteria. Three of the four were included in the Cochrane review; the fourth, the <a href="https://doi.org/10.1016/s0140-6736(72)92208-8">Finnish mental hospital study</a><a href="#fn-iPa8Phhvy9fzyWkHF-55" id="fnref-iPa8Phhvy9fzyWkHF-55">[55]</a>, was excluded for using a cluster-randomized design instead of full randomization. All four of these studies supported the hypothesis that reducing SFA improves cardiovascular health, and they had a weighted average relative risk of 0.71 (95% CI 0.62–0.81, see <a href="https://www.ahajournals.org/cms/10.1161/CIR.0000000000000510/asset/c991ecf0-a90b-4dbc-b9ff-27ad55c8b3a6/assets/graphic/e1fig02.jpeg">Figure 2</a>).
Two of the studies in the Cochrane review showed an increase in cardiovascular events when reducing SFA:
<ol>
<li>The <a href="https://doi.org/10.1136/bmj.e8707">Sydney Diet Heart study</a><a href="#fn-iPa8Phhvy9fzyWkHF-56" id="fnref-iPa8Phhvy9fzyWkHF-56">[56]</a> had some study participants replace saturated fat with trans-fat-heavy margarine, which likely explains the increase in bad outcomes.</li>
<li><a href="https://doi.org/10.1136/bmj.1.5449.1531">The Rose study</a><a href="#fn-iPa8Phhvy9fzyWkHF-57" id="fnref-iPa8Phhvy9fzyWkHF-57">[57]</a> did not have any glaring problems like Sydney Diet Heart, but it lasted for less than 2 years and only had a total of 54 participants. I take it as valid but weak contradictory evidence.</li>
</ol>
It looks reasonably likely, but not conclusive, that saturated fat is unhealthy. How unhealthy?
The Cochrane review suggests that an intervention to reduce dietary SFA should prevent one cardiovascular event per 290 person-years and one death per 2300 person-years for the sort of people who participated in these trials (i.e., people with elevated baseline risk of cardiovascular disease).<a href="#fn-iPa8Phhvy9fzyWkHF-58" id="fnref-iPa8Phhvy9fzyWkHF-58">[58]</a> Compare to exercise, which is associated with a reduction of about 1 death per 300 person-years in individuals with chronic diseases.<a href="#fn-iPa8Phhvy9fzyWkHF-59" id="fnref-iPa8Phhvy9fzyWkHF-59">[59]</a>
It's not clear how to estimate the improvement in mortality for the general population. Participants in these trials died at approximately the normal rate (compare to <a href="https://www.cdc.gov/nchs/fastats/deaths.htm">US CDC mortality statistics</a>) which suggests the effect should be similar, but it makes sense in theory that dietary interventions should have larger effects on unhealthy populations.
<h2>People should take omega-3 supplements</h2>
<blockquote>
There is some evidence that supplementation with the omega-3 fatty acid DHA, found in fish oil, may help maintain brain health[.] (page 200)
</blockquote>
<blockquote>
[U]nless they are eating a lot of fatty fish, filling their coffers with marine omega-3 [fatty acids], [my patients] almost always need to take EPA and DHA supplements in capsule or oil form. (page 339)
</blockquote>
My assessment:
<ul>
<li>Omega-3 fatty acids improve brain health: likely true (credence: 75%).</li>
<li>Omega-3s improve health in general: likely true (credence: 80%).</li>
<li>It's a good idea for most people to take omega-3 supplements: somewhat likely (credence: 65%).</li>
</ul>
A meta-analysis of RCTs by <a href="https://doi.org/10.7759/cureus.30091">Dighriri et al. (2022)</a><a href="#fn-iPa8Phhvy9fzyWkHF-60" id="fnref-iPa8Phhvy9fzyWkHF-60">[60]</a> found that "[c]onsumption of omega-3 improved learning, memory ability, cognitive well-being, and blood flow in the brain."
A <a href="https://doi.org/10.1002/14651858.cd003177.pub5">Cochrane review</a><a href="#fn-iPa8Phhvy9fzyWkHF-61" id="fnref-iPa8Phhvy9fzyWkHF-61">[61]</a> of RCTs found no statistically significant effect of omega-3 consumption on all-cause mortality, cardiovascular events, stroke, or arrhythmia, and a weakly statistically significant effect on cardiovascular mortality, coronary heart disease mortality, and coronary heart disease events. The non-significant effects were all positive, except for a small negative effect on stroke.<a href="#fn-iPa8Phhvy9fzyWkHF-62" id="fnref-iPa8Phhvy9fzyWkHF-62">[62]</a>
So omega-3s probably improve brain health, and they might have a small effect on heart health but it's unclear.
As far as we can tell, there are no significant downsides to dietary omega-3s, so they easily pass a cost-benefit analysis as long as you don't mind eating omega-3-rich foods.
The cost-benefit analysis for omega-3 supplementation is a bit murkier because supplements sometimes contain contaminants.<a href="#fn-iPa8Phhvy9fzyWkHF-63" id="fnref-iPa8Phhvy9fzyWkHF-63">[63]</a><a href="#fn-iPa8Phhvy9fzyWkHF-64" id="fnref-iPa8Phhvy9fzyWkHF-64">[64]</a> <a href="https://doi.org/10.1016/j.jfca.2016.09.008">Raab et al. (2016)</a><a href="#fn-iPa8Phhvy9fzyWkHF-65" id="fnref-iPa8Phhvy9fzyWkHF-65">[65]</a> tested 67 supplements and found that all had safe levels of heavy metals, but did not test for mercury. <a href="https://doi.org/10.1533/9780857098863.4.389">Winwood (2013)</a><a href="#fn-iPa8Phhvy9fzyWkHF-66" id="fnref-iPa8Phhvy9fzyWkHF-66">[66]</a> claims that algae oil typically comes from algae grown in tanks and thus can't be contaminated by heavy metals in the ocean.
I personally take a daily algae oil supplement. I take algae oil instead of fish oil because I'm vegan, but the potentially reduced risk of contaminants is a nice bonus.
<h1>Sleep</h1>
I read this chapter more skeptically than the others because it quoted Matthew Walker near the beginning. This raised some alarm bells because Walker wrote a <a href="https://guzey.com/books/why-we-sleep/">bad book</a> about sleep and has been caught <a href="https://statmodeling.stat.columbia.edu/2019/12/27/why-we-sleep-data-manipulation-a-smoking-gun/">manipulating data</a>.<a href="#fn-iPa8Phhvy9fzyWkHF-67" id="fnref-iPa8Phhvy9fzyWkHF-67">[67]</a> Outlive cited a few of Walker's papers to support certain claims, but none of those claims seemed particularly important so I didn't review them.<a href="#fn-iPa8Phhvy9fzyWkHF-68" id="fnref-iPa8Phhvy9fzyWkHF-68">[68]</a>
<h2>Every animal sleeps</h2>
<blockquote>
Every animal engages in some form of sleep; scientists have found no exceptions, so far. (page 353)
</blockquote>
My assessment:
<ul>
<li>Every animal sleeps: somewhat unlikely (credence: 35%).</li>
<li>It's reasonable to assert that every animal sleeps: false (credence: 20%).</li>
</ul>
In support of this claim, Outlive cites <a href="https://doi.org/10.1371/journal.pbio.0060216">Cirelli & Tononi (2008)</a><a href="#fn-iPa8Phhvy9fzyWkHF-69" id="fnref-iPa8Phhvy9fzyWkHF-69">[69]</a>, which does not take a strong stance on whether all animals sleep:
<blockquote>
Only a small number of species—mostly mammals and birds—have been evaluated in detail with respect to sleep. Most studies found signs of sleep, both behavioral (quiescence and hyporesponsivity) and electrophysiological (e.g., the slow waves of non-rapid eye movement (NREM) sleep). Scientists have been hesitant to attribute sleep to reptiles, amphibians, fish, and especially invertebrates, preferring the noncommittal term "rest" in the absence of electrophysiological signs resembling those of mammals and birds.
</blockquote>
Cirelli & Tononi (2008) references some examples of animals that have been claimed not to sleep (particularly bullfrogs), but says the evidence is weak.
I don't think Cirelli & Tononi supports Attia's claim; it would be more accurate to say "no animal has been proven not to sleep".
But other sources would disagree with this. For example:
<blockquote>
It now appears that many species reduce sleep for long periods of time under normal conditions and that others do not sleep at all, in the way sleep is conventionally defined.
</blockquote>
From Kushida, C. (2013). Encyclopedia of Sleep, Volume 1, page 38 (h/t <a href="https://guzey.com/books/why-we-sleep/">Alexey Guzey</a>).
Attia's claim "scientists have found no exceptions" is sort of true in the sense that we haven't found any definitive exceptions, but the claim "every animal engages in some form of sleep" isn't well-established either.
<h2>We need to sleep 7.5 to 8.5 hours a night</h2>
<blockquote>
[M]any, many studies have confirmed what your mother told you: We need to sleep about seven and a half to eight and a half hours a night. (page 354)
</blockquote>
My assessment: false (credence: 10%).
(I could not find a citation for the quoted assertion.)
The most authoritative source on this question appears to be the <a href="https://doi.org/10.1016/j.sleh.2014.12.010">National Sleep Foundation panel</a><a href="#fn-iPa8Phhvy9fzyWkHF-70" id="fnref-iPa8Phhvy9fzyWkHF-70">[70]</a>, where sleep scientists were surveyed on their beliefs. The median panelist believed that 7 to 9 hours a night is "appropriate" for adults age 25–64, and 6 to 10 hours "may be appropriate for some people" in the same age range.<a href="#fn-iPa8Phhvy9fzyWkHF-71" id="fnref-iPa8Phhvy9fzyWkHF-71">[71]</a>
The range given by Outlive (7.5 to 8.5 hours) is excessively narrow—according to sleep scientists, many people can/should sleep more or less than that.
My subjective uncertainty on this question mostly comes from the fact that I haven't read any studies or even any meta-analyses and I'm only 90% confident that the National Sleep Foundation panelists know what they're talking about.
<h2>Basketball players who were told to sleep for 10 hours a night had better shooting accuracy</h2>
<blockquote>
In one study, Stanford basketball players were encouraged to strive for ten hours of sleep per day, with or without naps, and to abstain from alcohol or caffeine. After five weeks, their shooting accuracy had improved by 9 percent, and their sprint times had also gotten faster. (page 354)
</blockquote>
I didn't look into this study and I'm not giving a credence because I don't really care about this particular claim. I bring it up because it contradicts the preceding claim that people should sleep 7.5 to 8.5 hours a night.
<h2>Lack of sleep increases obesity and diabetes risk</h2>
<blockquote>
Even in the short term, sleep deprivation can cause profound insulin resistance. [...] Multiple large meta-analyses of sleep studies have revealed a close relationship between sleep duration and risk of type 2 diabetes and the metabolic syndrome. (page 356)
</blockquote>
My assessment:
<ul>
<li>Sleep deprivation increases the risk of insulin resistance: highly likely (credence: 90%).</li>
<li>Observational studies find relationships between short sleep duration and obesity/diabetes/metabolic syndrome: true (credence: 95%).</li>
<li>Lack of sleep increases obesity and diabetes risk: highly likely (credence: 85%).</li>
</ul>
I only briefly investigated this but it passes a basic sanity check. I glanced at the papers cited by Outlive and they appear to support the quoted text. In addition, RCTs suggest that sleep restriction causes subjects to eat more and increases insulin resistance (a precursor to diabetes)—see meta-analysis by <a href="https://doi.org/10.1016/j.metabol.2018.02.010">Reutrakul & Van Cauter (2018)</a><a href="#fn-iPa8Phhvy9fzyWkHF-72" id="fnref-iPa8Phhvy9fzyWkHF-72">[72]</a>.
<h2>A study using Mendelian randomization found that sleeping <6 hours a night increased risk of a heart attack</h2>
<blockquote>
[O]ne particularly interesting study compared observational and Mendelian randomization<a href="#fn-iPa8Phhvy9fzyWkHF-73" id="fnref-iPa8Phhvy9fzyWkHF-73">[73]</a> data in people with previous identified genetic variants that either increase or decrease their lifelong exposure to longer or shorter sleep duration. The MR data confirmed the observational findings, that sleeping less than six hours a night was associated with about a 20 percent higher risk of a heart attack. (page 359)
</blockquote>
My assessment:
<ul>
<li>A study found that sleeping <6 hours a night increases heart attack risk: true (credence: 98%).</li>
<li>Sleeping <6 hours a night increases heart disease risk for most people: likely true (credence: 80%).</li>
<li>This quote from the book does a good job of representing the state of the evidence: false (credence: 10%).</li>
</ul>
In support of this quote, Attia cites <a href="https://doi.org/10.1038/s41467-019-08917-4">Dashti et al. (2019)</a><a href="#fn-iPa8Phhvy9fzyWkHF-74" id="fnref-iPa8Phhvy9fzyWkHF-74">[74]</a>, which does not appear to say anything about heart attacks. I believe he meant to cite <a href="https://doi.org/10.1016/j.jacc.2019.07.022">Daghlas et al. (2019)</a><a href="#fn-iPa8Phhvy9fzyWkHF-75" id="fnref-iPa8Phhvy9fzyWkHF-75">[75]</a> (on which Dashti is a co-author). Daghlas et al. (2019) supports Attia's claim.
However, other Mendelian randomization studies have gotten different results. <a href="https://doi.org/10.1186/s12944-020-01257-z">Zhuang et al. (2020)</a><a href="#fn-iPa8Phhvy9fzyWkHF-76" id="fnref-iPa8Phhvy9fzyWkHF-76">[76]</a> found no significant relationship between sleep duration and coronary heart disease; <a href="https://doi.org/10.1002%2Fehf2.14016">Yang et al. (2022)</a><a href="#fn-iPa8Phhvy9fzyWkHF-77" id="fnref-iPa8Phhvy9fzyWkHF-77">[77]</a> found a statistically significant but extremely weak ("probably not clinically relevant") association<a href="#fn-iPa8Phhvy9fzyWkHF-78" id="fnref-iPa8Phhvy9fzyWkHF-78">[78]</a>; while <a href="https://doi.org/10.1016/j.sleep.2019.08.014">Liao et al. (2020)</a><a href="#fn-iPa8Phhvy9fzyWkHF-79" id="fnref-iPa8Phhvy9fzyWkHF-79">[79]</a> broadly agreed with Daghlas et al. (2019).
Out of four Mendelian randomization studies, two identified strong links between short sleep and heart disease/heart attack risk, and two suggested little to no effect. So while Outlive does accurately describe the results of a study, it misrepresents the evidence by ignoring the studies that contradict its thesis.
(I did not look into the quality of these studies, I just read their conclusions. It's possible that the null-result studies are flawed in some way.)
The Mendelian randomization studies provide only weak to moderate evidence, but when combined with other evidence (such as the link to obesity discussed in the previous section), it appears reasonably likely that short sleep duration does indeed increase the risk of heart problems.
<h2>Lack of sleep causes Alzheimer's disease</h2>
<blockquote>
<ol>
<li>Subsequent research ... has pointed to chronic bad sleep as a powerful potential cause of Alzheimer's disease and dementia. Sleep, it turns out, is as crucial to maintaining brain health as it is to brain function.</li>
</ol>
</blockquote>
My assessment:
<ul>
<li>Lack of sleep causes Alzheimer's disease: possibly true (credence: 60%).</li>
<li>The first sentence of the book quote is reasonable: true (credence: 90%).</li>
<li>The second sentence of the book quote is reasonable: false (credence: 20%).</li>
</ul>
Some research has indeed found a link between bad sleep and Alzheimer's, but it's difficult to establish causality—see review article by <a href="https://doi.org/10.3390%2Fijms21031168">Lloret et al. (2020)</a><a href="#fn-iPa8Phhvy9fzyWkHF-80" id="fnref-iPa8Phhvy9fzyWkHF-80">[80]</a>.
The first quoted sentence from Outlive aligns with Lloret et al.'s summary of the literature. The second sentence converts a speculative hypothesis into a certainty.
<h1>Bonus</h1>
<h2>Dunning-Kruger effect</h2>
<blockquote>
Looking back, I now realize that I was too far on the left of the Dunning-Kruger curve, caricatured below in figure 14—my maximal confidence and relatively minimal knowledge having propelled me quite close to the summit of "Mount Stupid." (page 293)
</blockquote>
The book's Figure 14 reproduces this image from Wikimedia Commons:
<img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/QqTiCz2Xz96MuEFsF/xqcns5ekfcn8tnpgzj6r" alt="">
My assessment:
<ul>
<li>This graph accurately represents the Dunning-Kruger effect: false (credence: <1%).</li>
<li>The existence of a "Mount Stupid" is supported by the scientific evidence: false (credence: 2%).</li>
</ul>
I'm willing to forgive this mistake because it doesn't have anything to do with longevity, but it still bugs me.
If you search "Dunning Kruger" on Google Images, you will see a bunch of graphs that look like that, but no study on the Dunning-Kruger effect has ever produced empirical data with that shape.
Empirical results actually look something like this:
<img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/QqTiCz2Xz96MuEFsF/bcfwmfxnktsjdgsljxvc" alt="">
(Presumably, Attia found Figure 14 from the Wikipedia page on the Dunning-Kruger effect. I can't really blame him for getting something wrong if he just pulled it from Wikipedia. And to Wikipedia's credit, it has removed the incorrect image and replaced it with the correct one above.)
<hr class="footnotes-sep">
<section class="footnotes">
<ol class="footnotes-list">
<li id="fn-iPa8Phhvy9fzyWkHF-1" class="footnote-item">The book is co-authored by Bill Gifford. It's written from Attia's point of view and some materials (such as <a href="https://peterattiamd.com/outlive/">Peter Attia's website</a>) approximately treat Attia as the sole author, so in my review I will credit the book's claims to Attia and not to Gifford. <a href="#fnref-iPa8Phhvy9fzyWkHF-1" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-2" class="footnote-item">Page numbers are from the 2023 Kindle edition of Outlive, ISBN 9780593236598, ebook ISBN 9780593236604. <a href="#fnref-iPa8Phhvy9fzyWkHF-2" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-3" class="footnote-item">The meta-analysis did definitely find this result, but there's some wiggle room around what "technically correct" means (because the meta-analysis found different results for different subgroups—I will discuss this shortly). So I'm only 90% confident. <a href="#fnref-iPa8Phhvy9fzyWkHF-3" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-4" class="footnote-item">Stefan, N., Schick, F., & Häring, H. U. (2017). <a href="https://doi.org/10.1016/j.cmet.2017.07.008">Causes, Characteristics, and Consequences of Metabolically Unhealthy Normal Weight in Humans.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-4" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-5" class="footnote-item">Kramer, C. K., Zinman, B., and Retnakaran, R (2013). <a href="/materials/kramer2013.pdf">Are metabolically healthy overweight and obesity benign conditions? A systematic review and meta-analysis.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-5" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-6" class="footnote-item">The standard method for significance-testing a relative risk is to assume that its logarithm follows a normal distribution. I did that and got an odds ratio of 7.27. But the sample mean of 1.19 is pretty far from the geometric mean of the 95% CI (1.16), and much closer to its arithmetic mean (1.18), so I redid the test with the assumption that the RR follows a normal distribution. The second method produces an odds ratio of 5.66, which I rounded down to 5 to be conservative.
It's bad practice to run two different significance tests, but I think it's okay in this case because I preferred the test that weakened my argument rather than strengthening it. <a href="#fnref-iPa8Phhvy9fzyWkHF-6" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-7" class="footnote-item">The original article used PubMed links, which I replaced with DOI links and added full citations in footnotes. The quote is otherwise unchanged. <a href="#fnref-iPa8Phhvy9fzyWkHF-7" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-8" class="footnote-item">Lin, H., Zhang, L., Zheng, R., & Zheng, Y. (2017). <a href="https://doi.org/10.1097/md.0000000000008838">The prevalence, metabolic risk and effects of lifestyle intervention for metabolically healthy obesity.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-8" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-9" class="footnote-item">Eckel, N., Meidtner, K., Kalle-Uhlmann, T., Stefan, N., and Schulze, M. B (2016). <a href="https://pubmed.ncbi.nlm.nih.gov/26701871/">Metabolically healthy obesity and cardiovascular events: a systematic review and meta-analysis.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-9" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-10" class="footnote-item">Kim, T. J., Shin, H. Y., Chang, Y., Kang, M., Jee, J., Choi, Y. H., Ahn, H. S., Ahn, S. H., Son, H. J., & Ryu, S. (2017). <a href="https://doi.org/10.1016/j.atherosclerosis.2017.03.035">Metabolically healthy obesity and the risk for subclinical atherosclerosis.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-10" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-11" class="footnote-item">Chang, Y., Jung, H. S., Cho, J., Zhang, Y., Yun, K. E., Lazo, M., Pastor-Barriuso, R., Ahn, J., Kim, C. W., Rampal, S., Cainzos-Achirica, M., Zhao, D., Chung, E. C., Shin, H., Guallar, E., & Ryu, S. (2016). <a href="https://doi.org/10.1038/ajg.2016.178">Metabolically Healthy Obesity and the Development of Nonalcoholic Fatty Liver Disease.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-11" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-12" class="footnote-item">Chang, A. R., Surapaneni, A., Kirchner, H. L., Young, A., Kramer, H. J., Carey, D. J., Appel, L. J., & Grams, M. E. (2018). <a href="https://doi.org/10.1002/oby.22134">Metabolically Healthy Obesity and Risk of Kidney Function Decline.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-12" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-13" class="footnote-item">Bell, J. A., Kivimaki, M., & Hamer, M. (2014). <a href="https://doi.org/10.1111/obr.12157">Metabolically healthy obesity and risk of incident type 2 diabetes: a meta‐analysis of prospective cohort studies.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-13" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-14" class="footnote-item">When Attia says the amyloid theory was weakening, he's referring to the once-popular hypothesis that amyloid-beta is the sole cause of Alzheimer's. That hypothesis now appears to be false, but amyloid-beta still looks relevant to Alzheimer's somehow (it's not quite clear how). <a href="#fnref-iPa8Phhvy9fzyWkHF-14" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-15" class="footnote-item">Actually, I have very good reading comprehension in a relative sense—in the 98th or 99th percentile according to standardized tests. But 98th percentile reading comprehension still isn't good enough to consistently understand the things you read, apparently. <a href="#fnref-iPa8Phhvy9fzyWkHF-15" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-16" class="footnote-item">I'm not confident in the claim that they're more accurate. I am not aware of any research directly comparing the predictive power of VO2max itself vs. performance tests. In theory, I would expect performance tests to be better predictors because they're directly measuring your body's physical capabilities. <a href="#fnref-iPa8Phhvy9fzyWkHF-16" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-17" class="footnote-item">Some special-purpose interventions might work better. For example, if you're a heavy smoker, quitting smoking might have a bigger effect than starting exercise. <a href="#fnref-iPa8Phhvy9fzyWkHF-17" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-18" class="footnote-item">Kokkinos, P., Faselis, C., Samuel, I. B. H., Pittaras, A., Doumas, M., Murphy, R., Heimall, M. S. et al. (2022). <a href="https://doi.org/10.1016/j.jacc.2022.05.031">Cardiorespiratory Fitness and Mortality Risk Across the Spectra of Age, Race, and Sex.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-18" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-19" class="footnote-item">Mandsager, K., Harb, S., Cremer, P., Phelan, D., Nissen, S. E., & Jaber, W. (2018). <a href="https://doi.org/10.1001/jamanetworkopen.2018.3605">Association of Cardiorespiratory Fitness With Long-term Mortality Among Adults Undergoing Exercise Treadmill Testing.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-19" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-20" class="footnote-item">Harber, M. P., Kaminsky, L. A., Arena, R., Blair, S. N., Franklin, B. A., Myers, J., & Ross, R. (2017). <a href="https://doi.org/10.1016/j.pcad.2017.03.001">Impact of Cardiorespiratory Fitness on All-Cause and Disease-Specific Mortality: Advances Since 2009.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-20" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-21" class="footnote-item">Wen, D., Utesch, T., Wu, J., Robertson, S., Liu, J., Hu, G., & Chen, H. (2019). <a href="https://doi.org/10.1016/j.jsams.2019.01.013">Effects of different protocols of high intensity interval training for VO2max improvements in adults: A meta-analysis of randomised controlled trials.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-21" class="footnote-backref">↩︎</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-21:1" class="footnote-backref">↩︎</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-21:2" class="footnote-backref">↩︎</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-21:3" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-22" class="footnote-item">Seiler, S. (2010). <a href="https://doi.org/10.1123/ijspp.5.3.276">What is Best Practice for Training Intensity and Duration Distribution in Endurance Athletes?.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-22" class="footnote-backref">↩︎</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-22:1" class="footnote-backref">↩︎</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-22:2" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-23" class="footnote-item">Billat, L. V. (2001). <a href="https://doi.org/10.2165/00007256-200131010-00002">Interval Training for Performance: A Scientific and Empirical Practice.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-23" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-24" class="footnote-item">Billat, V., Renoux, J. C., Pinoteau, J., Petit, B., & Koralsztein, J. P. (1995). <a href="https://doi.org/10.3109/13813459508996126">Times to exhaustion at 90,100 and 105% of velocity at V̇O2max (Maximal aerobic speed) and critical speed in elite longdistance runners.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-24" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-25" class="footnote-item"><a href="/materials/blondel2001.pdf">Blondel et al. (2001)</a><a href="#fn-iPa8Phhvy9fzyWkHF-90" id="fnref-iPa8Phhvy9fzyWkHF-90">[90]</a> found that a sample of physically active (but not elite) students could sustain 90% of VO2max for an average of 13.98 minutes. <a href="#fnref-iPa8Phhvy9fzyWkHF-25" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-26" class="footnote-item">Different people use terminology in different ways. I am using LIT to refer to what Attia calls zone 2. Some studies call it moderate-intensity continuous training (MICT). Colloquially, it refers to an exercise intensity that you can sustain for a long time. Technically, it refers to exercise at or below the <a href="https://en.wikipedia.org/wiki/Lactate_threshold">lactate threshold</a>. <a href="#fnref-iPa8Phhvy9fzyWkHF-26" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-27" class="footnote-item">Crowley, E., Powell, C., Carson, B. P., & W. Davies, R. (2022). <a href="https://doi.org/10.1155/2022/9310710">The Effect of Exercise Training Intensity on VO2max in Healthy Adults: An Overview of Systematic Reviews and Meta-Analyses.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-27" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-28" class="footnote-item">It may be possible to resolve this inconsistency by digging deeper into the literature. Some relevant questions:
<ol>
<li>Wen et al. (2019)<a href="#fn-iPa8Phhvy9fzyWkHF-21" id="fnref-iPa8Phhvy9fzyWkHF-21:3">[21:3]</a> found that long-duration HIIT worked better than short-duration. For the studies that find no benefit to HIIT over LIT, are they only looking at short-duration HIIT?</li>
<li>Some RCTs match volume between groups. So if the HIIT group spends a total of (say) 16 minutes at high intensity, then the LIT group exercises for 16 minutes total. That's not how people actually exercise. Do meta-analyses understate the benefits of LIT because they include volume-matched studies?</li>
<li>How do the returns to HIIT vs. LIT differ for novice vs. experienced athletes?</li>
<li>What happens when you combine HIIT with LIT?</li>
</ol>
<a href="#fnref-iPa8Phhvy9fzyWkHF-28" class="footnote-backref">↩︎</a></li>
<li id="fn-iPa8Phhvy9fzyWkHF-29" class="footnote-item">Mølmen, K. S., Almquist, N. W., & Skattebo, Ø. (2024). <a href="https://doi.org/10.1007/s40279-024-02120-2">Effects of Exercise Training on Mitochondrial and Capillary Growth in Human Skeletal Muscle: A Systematic Review and Meta-Regression.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-29" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-30" class="footnote-item">Stöggl, T. L., & Sperlich, B. (2015). <a href="https://doi.org/10.3389/fphys.2015.00295">The training intensity distribution among well-trained and elite endurance athletes.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-30" class="footnote-backref">↩︎</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-30:1" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-31" class="footnote-item">Frank, C., Kobesova, A., and Kolar, P (2013). <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3578435/">Dynamic neuromuscular stabilization & sports rehabilitation.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-31" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-32" class="footnote-item">I'm thinking in particular of <a href="https://doi.org/10.1519/JSC.0000000000004655">Chiu (2023)</a><a href="#fn-iPa8Phhvy9fzyWkHF-82" id="fnref-iPa8Phhvy9fzyWkHF-82">[82]</a> which investigated knee valgus, a squat technique that was generally regarded as bad form, and found that it may be better than "correct" form. h/t <a href="https://www.youtube.com/watch?v=UOWQUNZRVtU">Menno Henselmans</a>. <a href="#fnref-iPa8Phhvy9fzyWkHF-32" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-33" class="footnote-item">Sherrington, C., Tiedemann, A., Fairhall, N., Close, J. C. T., & Lord, S. R. (2011). <a href="https://doi.org/10.1071/NB10056">Exercise to prevent falls in older adults: an updated meta-analysis and best practice recommendations.</a>. doi: <a href="https://doi.org/10.1071/nb10056">10.1071/nb10056</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-33" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-34" class="footnote-item">de Souto Barreto, P., Rolland, Y., Vellas, B., & Maltais, M. (2019). <a href="https://doi.org/10.1001/jamainternmed.2018.5406">Association of Long-term Exercise Training With Risk of Falls, Fractures, Hospitalizations, and Mortality in Older Adults.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-34" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-35" class="footnote-item">Kümmel, J., Kramer, A., Giboin, L. S., & Gruber, M. (2016). <a href="https://link.springer.com/article/10.1007/s40279-016-0515-z">Specificity of Balance Training in Healthy Individuals: A Systematic Review and Meta-Analysis.</a>. doi: <a href="https://doi.org/10.1007/s40279-016-0515-z">10.1007/s40279-016-0515-z</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-35" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-36" class="footnote-item">Colman, R. J., Anderson, R. M., Johnson, S. C., Kastman, E. K., Kosmatka, K. J., Beasley, T. M., Allison, D. B., Cruzen, C., Simmons, H. A., Kemnitz, J. W., & Weindruch, R. (2009). <a href="https://doi.org/10.1126/science.1173635">Caloric Restriction Delays Disease Onset and Mortality in Rhesus Monkeys.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-36" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-37" class="footnote-item">Mattison, J. A., Roth, G. S., Beasley, T. M., Tilmont, E. M., Handy, A. M., Herbert, R. L., Longo, D. L., Allison, D. B., Young, J. E., Bryant, M., Barnard, D., Ward, W. F., Qi, W., Ingram, D. K., & de Cabo, R. (2012). <a href="https://doi.org/10.1038/nature11432">Impact of caloric restriction on health and survival in rhesus monkeys from the NIA study.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-37" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-38" class="footnote-item">Mattison, J. A., Colman, R. J., Beasley, T. M., Allison, D. B., Kemnitz, J. W., Roth, G. S., Ingram, D. K., Weindruch, R., de Cabo, R., & Anderson, R. M. (2017). <a href="https://doi.org/10.1038/ncomms14063">Caloric restriction improves health and survival of rhesus monkeys.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-38" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-39" class="footnote-item">Actually, the NIA young female cohort did see a statistically significant reduction in lifespan (p = 0.04), but it becomes non-significant if you do a Bonferroni correction. <a href="#fnref-iPa8Phhvy9fzyWkHF-39" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-40" class="footnote-item">Mean and 95% confidence intervals for change in longevity from various study cohorts:
| Cohort | Mean | 95% CI |
|------------------+-------+----------------|
| UW male | 1.58 | (-1.56, 4.72) |
| UW female | 2.22 | (-2.74, 7.18) |
| NIA young male | -2.29 | (-7.05, 2.47) |
| NIA young female | -4.79 | (-8.88, -0.70) |
The CI for NIA young male contains the mean for UW male but the reverse is not true, and neither female cohort's CI contains the mean of the other. <a href="#fnref-iPa8Phhvy9fzyWkHF-40" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-41" class="footnote-item">If true, we would expect to find that calorie restriction worked for the NIA young male cohort because they ate about as much as their UW counterparts. But it didn't work (in fact it shortened the average lifespan). <a href="#fnref-iPa8Phhvy9fzyWkHF-41" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-42" class="footnote-item">I can think of several other hypotheses.
The UW control group ate ad libitum, which is fancy academic language for "as much as they want". The NIA control group didn't eat ad libitum. Instead, the researchers used previous data to determine how much monkeys tend to eat when fed ad libitum (controlling for age and bodyweight) and then fed subjects exactly that amount.
This brings to mind another hypothesis: Maybe some portion (let's say 1/3) of monkeys tend to overeat, which causes health problems, and calorie restriction mainly only benefits the 1/3 who overeat. If the NIA control monkeys all received diets based on how much the average monkey eats, that prevents the most gluttonous 1/3 from overeating, so additional calorie restriction doesn't produce meaningful benefits.
You could test this hypothesis using the UW data by dividing monkeys in the calorie restriction cohort into "high-calorie" and "low-calorie" group based on how much they ate ad libitum (controlling for age and bodyweight) and seeing if the high-calorie group had a bigger improvement in longevity than the low-calorie group. The groups would have small sample sizes so the result probably wouldn't be statistically significant.
Some weak supporting evidence: in the UW study, the median longevity improvement was bigger than the mean improvement.
A fourth hypothesis: calorie restriction has a U-shaped effect on longevity, where a little calorie restriction helps, but excess calorie restriction increases mortality. (This is clearly true in the limit—100% calorie restriction certainly isn't healthy.)
The studies weakly contradict this hypothesis. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5247583/figure/f4/">Figure 4</a> shows that NIA young males in the control group ate about as much as UW males, while in the other three control group pairings (NIA young female + UW female, NIA old male + UW male, NIA old female + UW female), the NIA group ate less. This predicts that calorie restriction should improve longevity in the NIA young male cohort but have a smaller or negative effect in the other three cohorts. But that's not what the NIA study found. Instead, the young male and young female cohorts both saw decreased longevity from calorie restriction, and both old cohorts saw approximately no effect.
A fifth hypothesis: the studies have fundamental methodological issues that render the results invalid. The studies weakly support this hypothesis given how many peculiar and seemingly-contradictory findings I was able to identify.
I don't know what those methodological issues might be. They could be things like:
<ul>
<li>the different cohorts were managed by different researchers who used inconsistent procedures</li>
<li>the cohorts had relevantly different genetic lineages</li>
<li>the researchers fabricated data (probably not, but you never know)</li>
<li>there was a mold infestation next to the control group's cages</li>
</ul>
A sixth hypothesis: calorie restriction works, but only if you live in Wisconsin. <a href="#fnref-iPa8Phhvy9fzyWkHF-42" class="footnote-backref">↩︎</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-42:1" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-43" class="footnote-item">Mattison, J. A., Black, A., Huck, J., Moscrip, T., Handy, A., Tilmont, E., Roth, G. S., Lane, M. A., & Ingram, D. K. (2005). <a href="https://doi.org/10.1016/j.neurobiolaging.2004.09.013">Age-related decline in caloric intake and motivation for food in rhesus monkeys.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-43" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-44" class="footnote-item">Yamada, Y., Colman, R. J., Kemnitz, J. W., Baum, S. T., Anderson, R. M., Weindruch, R., & Schoeller, D. A. (2013). <a href="https://doi.org/10.1016/j.exger.2013.08.002">Long-term calorie restriction decreases metabolic cost of movement and prevents decrease of physical activity during aging in rhesus monkeys.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-44" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-45" class="footnote-item"><a href="https://doi.org/10.1161/CIRCRESAHA.115.306883">Ortega et al. (2016)</a><a href="#fn-iPa8Phhvy9fzyWkHF-83" id="fnref-iPa8Phhvy9fzyWkHF-83">[83]</a> summarizes the relevant literature. Several observational studies have found that overweight but physically fit individuals have little to no increase in mortality rates relative to normal-weight fit individuals (the largest study<a href="#fn-iPa8Phhvy9fzyWkHF-84" id="fnref-iPa8Phhvy9fzyWkHF-84">[84]</a> found a statistically significant but small effect (RR = 1.1); three other studies found no significant effect). By comparison, unfit people had 2–3x higher mortality than fit individuals. <a href="https://www.ahajournals.org/cms/10.1161/CIRCRESAHA.115.306883/asset/b702242c-ad02-4b6c-95b7-b60f578a8c73/assets/graphic/1752fig02.jpeg">Figure 2</a> (reproduced below) summarizes the results from the four studies.
<img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/QqTiCz2Xz96MuEFsF/rotiurnrndttap84moq0" alt="">
This finding from Ortega et al. (2016) is actually stronger than necessary for our purposes. It would be sufficient to say that exercise cancels out the harm of high-calorie diets by burning off the excess calories. But this shows that exercise (mostly) cancels out the harm even for people who don't lose weight. <a href="#fnref-iPa8Phhvy9fzyWkHF-45" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-46" class="footnote-item">Hooper, L., Martin, N., Jimoh, O. F., Kirk, C., Foster, E., & Abdelhamid, A. S. (2020). <a href="https://doi.org/10.1002/14651858.cd011737.pub3">Reduction in saturated fat intake for cardiovascular disease.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-46" class="footnote-backref">↩︎</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-46:1" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-47" class="footnote-item">Arguably, my credence for this latter claim should be higher than for the former claim, because reducing saturated fat has some chance of improving health and essentially no chance of harming health. But reducing saturated fat also has some costs (it makes your diet harder to follow).
In other words, on a cost-benefit analysis aimed at maximizing health, it's clearly worth it to eat less saturated fat. But on an all-things-considered cost-benefit analysis, there's more room for debate. <a href="#fnref-iPa8Phhvy9fzyWkHF-47" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-48" class="footnote-item">Zong, G., Li, Y., Wanders, A. J., Alssema, M., Zock, P. L., Willett, W. C., Hu, F. B. et al. (2016). <a href="https://doi.org/10.1136/bmj.i5796">Intake of individual saturated fatty acids and risk of coronary heart disease in US men and women: two prospective longitudinal cohort studies.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-48" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-49" class="footnote-item">Heileson, J. L. (2019). <a href="https://doi.org/10.1093/nutrit/nuz091">Dietary saturated fat and heart disease: a narrative review.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-49" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-50" class="footnote-item">Mensink, R. P., & World Health Organization (2016). <a href="https://iris.who.int/bitstream/handle/10665/246104/9789241565349-eng.pdf">Effects of saturated fatty acids on serum lipids and lipoproteins: a systematic review and regression analysis.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-50" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-51" class="footnote-item">Navarese, E. P., Robinson, J. G., Kowalewski, M., Kolodziejczak, M., Andreotti, F., Bliden, K., Tantry, U. et al. (2018). <a href="https://doi.org/10.1001/jama.2018.2525">Association Between Baseline LDL-C Level and Total and Cardiovascular Mortality After LDL-C Lowering.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-51" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-52" class="footnote-item">Ennezat, P. V., Guerbaai, R. A., Maréchaux, S., Le Jemtel, T. H., & François, P. (2022). <a href="https://doi.org/10.1097/fjc.0000000000001345">Extent of LDL-cholesterol Reduction and All-cause and Cardiovascular Mortality Benefit: a Systematic Review and Meta-analysis.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-52" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-53" class="footnote-item">Bergeron, N., Chiu, S., Williams, P. T., M King, S., & Krauss, R. M. (2019). <a href="https://doi.org/10.1093/ajcn/nqz035">Effects of red meat, white meat, and nonmeat protein sources on atherogenic lipoprotein measures in the context of low compared with high saturated fat intake: a randomized controlled trial.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-53" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-54" class="footnote-item">Sacks, F. M., Lichtenstein, A. H., Wu, J. H. Y., Appel, L. J., Creager, M. A., Kris-Etherton, P. M., Miller, M. et al. (2017). <a href="https://www.ahajournals.org/doi/full/10.1161/CIR.0000000000000510">Dietary Fats and Cardiovascular Disease: A Presidential Advisory From the American Heart Association.</a>. doi: <a href="https://doi.org/10.1161/cir.0000000000000510">10.1161/cir.0000000000000510</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-54" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-55" class="footnote-item">Miettinen, M., Karvonen, M., Turpeinen, O., Elosuo, R., & Paavilainen, E. (1972). <a href="https://doi.org/10.1016/s0140-6736(72)92208-8">EFFECT OF CHOLESTEROL-LOWERING DIET ON MORTALITY FROM CORONARY HEART-DISEASE AND OTHER CAUSES.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-55" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-56" class="footnote-item">Ramsden, C. E., Zamora, D., Leelarthaepin, B., Majchrzak-Hong, S. F., Faurot, K. R., Suchindran, C. M., Ringel, A. et al. (2013). <a href="https://doi.org/10.1136/bmj.e8707">Use of dietary linoleic acid for secondary prevention of coronary heart disease and death: evaluation of recovered data from the Sydney Diet Heart Study and updated meta-analysis.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-56" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-57" class="footnote-item">Rose, G. A., Thomson, W. B., & Williams, R. T. (1965). <a href="https://doi.org/10.1136/bmj.1.5449.1531">Corn Oil in Treatment of Ischaemic Heart Disease.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-57" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-58" class="footnote-item">The Cochrane review <a href="https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD011737.pub3/full#CD011737-sec-0008">summary of findings</a> reports that the interventions prevented 2 deaths per 1000 participants and the interventions lasted an average of 56 months, which equates to one death per 2300 pers <a href="#fnref-iPa8Phhvy9fzyWkHF-58" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-59" class="footnote-item">See <a href="https://doi.org/10.1001/jamainternmed.2015.0533">Arem et al. (2015)</a><a href="#fn-iPa8Phhvy9fzyWkHF-85" id="fnref-iPa8Phhvy9fzyWkHF-85">[85]</a> and <a href="https://doi.org/10.1161/circulationaha.121.058162">Lee et al. (2022)</a><a href="#fn-iPa8Phhvy9fzyWkHF-86" id="fnref-iPa8Phhvy9fzyWkHF-86">[86]</a>.
These were pooled analyses of cohort studies, not RCTs. I could not quickly find reliable RCT numbers.
Neither of these studies reported deaths prevented per person-year. I calculated the numbers using provided relative risks multiplied by number of deaths per person, divided by follow-up time. Number of years per death prevented varied based on exercise duration and intensity. I found that exercise prevented approximately one death per 300 years when defining "exercise" as 7.5+ MET-hours/week for Arem et al. (2015) and 150–224 minutes of moderate physical activity for Lee et al. (2022) (these two definitions are roughly equivalent).
There are a number of meta-analyses of RCTs, for example:
<ul>
<li><a href="https://doi.org/10.1016/j.ahj.2011.07.017">Lawler et al. (2011)</a><a href="#fn-iPa8Phhvy9fzyWkHF-87" id="fnref-iPa8Phhvy9fzyWkHF-87">[87]</a> found exercise had a relative risk (RR) of 0.74 on all-cause mortality for individuals who had experienced heart attacks.</li>
<li><a href="https://doi.org/10.1177/1534735420917462">Morishita et al. (2020)</a><a href="#fn-iPa8Phhvy9fzyWkHF-88" id="fnref-iPa8Phhvy9fzyWkHF-88">[88]</a> found RR = 0.76 on cancer mortality for cancer patients.</li>
</ul>
However, neither of these meta-analyses provided per-group mortality numbers or mean intervention length, so I can't determine the number of years per death prevented without reading through every individual study. Based on the RRs, my guess is that these meta-analyses would give roughly similar numbers to the pooled analyses above.
To my knowledge, the most comprehensive meta-analysis is <a href="https://doi.org/10.1186/s12889-020-09855-3">Posadzki et al. (2020)</a><a href="#fn-iPa8Phhvy9fzyWkHF-89" id="fnref-iPa8Phhvy9fzyWkHF-89">[89]</a>, which reviewed 150 different Cochrane reviews and found an RR of 0.87 for all-cause mortality. But it provides even less information about the participants so I have no way of interpreting this number. <a href="#fnref-iPa8Phhvy9fzyWkHF-59" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-60" class="footnote-item">Dighriri, I. M., Alsubaie, A. M., Hakami, F. M., Hamithi, D. M., Alshekh, M. M., Khobrani, F. A., Dalak, F. E. et al. (2022). <a href="https://doi.org/10.7759/cureus.30091">Effects of Omega-3 Polyunsaturated Fatty Acids on Brain Functions: A Systematic Review.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-60" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-61" class="footnote-item">Abdelhamid, A. S., Brown, T. J., Brainard, J. S., Biswas, P., Thorpe, G. C., Moore, H. J., Deane, K. H. et al. (2020). <a href="https://doi.org/10.1002/14651858.cd003177.pub5">Omega-3 fatty acids for the primary and secondary prevention of cardiovascular disease.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-61" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-62" class="footnote-item">When talking about the <a href="#Rhesus_monkey_studies_suggest_that_calorie_restriction_improves_longevity_but_only_if_you_eat_a_fairly_unhealthy_diet">calorie restriction studies</a>, I said that a negative effect is a red flag even if it's non-significant. In this case I'm not too concerned because:
<ul>
<li>The effect on stroke was highly non-significant (p = 0.82). Compare to the NIA calorie restriction study which had p = 0.35 and p = 0.02 for young males and young females respectively.</li>
<li>RCTs show omega-3s improve short-term brain function.</li>
</ul>
I think the most reasonable interpretation is that there's no effect on stroke. <a href="#fnref-iPa8Phhvy9fzyWkHF-62" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-63" class="footnote-item">Jacobs, M. N., Covaci, A., Gheorghe, A., & Schepens, P. (2004). <a href="https://doi.org/10.1021/jf035310q">Time Trend Investigation of PCBs, PBDEs, and Organochlorine Pesticides in Selected n−3 Polyunsaturated Fatty Acid Rich Dietary Fish Oil and Vegetable Oil Supplements; Nutritional Relevance for Human Essential n−3 Fatty Acid Requirements.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-63" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-64" class="footnote-item">Fernandes, A. R., Rose, M., White, S., Mortimer, D. N., & Gem, M. (2006). <a href="https://doi.org/10.1080/02652030600660827">Dioxins and polychlorinated biphenyls (PCBs) in fish oil dietary supplements: Occurrence and human exposure in the UK.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-64" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-65" class="footnote-item">Raab, A., Stiboller, M., Gajdosechova, Z., Nelson, J., & Feldmann, J. (2016). <a href="https://doi.org/10.1016/j.jfca.2016.09.008">Element content and daily intake from dietary supplements (nutraceuticals) based on algae, garlic, yeast fish and krill oils—Should consumers be worried?.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-65" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-66" class="footnote-item">Winwood, R. J. (2013). <a href="https://doi.org/10.1533/9780857098863.4.389">Algal oil as a source of omega-3 fatty acids.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-66" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-67" class="footnote-item">See also Walker's <a href="https://sleepdiplomat.wordpress.com/2019/12/19/why-we-sleep-responses-to-questions-from-readers/#Sleep_injury">response</a> on why he presented the data the way he did. <a href="#fnref-iPa8Phhvy9fzyWkHF-67" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-68" class="footnote-item">For example, the book cites <a href="https://doi.org/10.1523/JNEUROSCI.5254-14.2015">Goldstein-Piekarski et al. (2015)</a><a href="#fn-iPa8Phhvy9fzyWkHF-81" id="fnref-iPa8Phhvy9fzyWkHF-81">[81]</a> (Walker being a co-author) for the passage "When we are deprived of REM, studies have found, we have a more difficult time reading others' facial expressions." I was skeptical of this statement even before knowing Walker co-authored the paper because it has the vibe of the sort of fun quirky result that doesn't survive the replication crisis. But I don't particularly care about this claim (it's not actionable in any way) so I didn't bother to investigate it.
(Also, this is a nitpick but the quoted passage says "studies have found" while only citing a single study.) <a href="#fnref-iPa8Phhvy9fzyWkHF-68" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-69" class="footnote-item">Cirelli, C., & Tononi, G. (2008). <a href="https://doi.org/10.1371/journal.pbio.0060216">Is Sleep Essential?</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-69" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-70" class="footnote-item">Hirshkowitz, M., Whiton, K., Albert, S. M., Alessi, C., Bruni, O., DonCarlos, L., Hazen, N., Herman, J., Katz, E. S., Kheirandish-Gozal, L., Neubauer, D. N., O’Donnell, A. E., Ohayon, M., Peever, J., Rawding, R., Sachdeva, R. C., Setters, B., Vitiello, M. V., Ware, J. C., & Adams Hillard, P. J. (2015). <a href="https://doi.org/10.1016/j.sleh.2014.12.010">National Sleep Foundation’s sleep time duration recommendations: methodology and results summary.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-70" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-71" class="footnote-item">They gave different recommended sleep durations for different age ranges. This table reproduces all the recommendations for individuals age 6 and up (since I assume nobody under 6 is reading this):
<table>
<thead>
<tr>
<th>Age</th>
<th>Recommended</th>
<th>May be appropriate</th>
</tr>
</thead>
<tbody>
<tr>
<td>6–13 y</td>
<td>9 to 11</td>
<td>7 to 12</td>
</tr>
<tr>
<td>14–17 y</td>
<td>8 to 10</td>
<td>7 to 11</td>
</tr>
<tr>
<td>18–25 y</td>
<td>7 to 9</td>
<td>6 to 11</td>
</tr>
<tr>
<td>26–64 y</td>
<td>7 to 9</td>
<td>6 to 10</td>
</tr>
<tr>
<td>>64 y</td>
<td>7 to 8</td>
<td>5 to 9</td>
</tr>
</tbody>
</table>
<a href="#fnref-iPa8Phhvy9fzyWkHF-71" class="footnote-backref">↩︎</a></li>
<li id="fn-iPa8Phhvy9fzyWkHF-72" class="footnote-item">Reutrakul, S., & Van Cauter, E. (2018). <a href="https://doi.org/10.1016/j.metabol.2018.02.010">Sleep influences on obesity, insulin resistance, and risk of type 2 diabetes.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-72" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-73" class="footnote-item"><a href="https://en.wikipedia.org/wiki/Mendelian_randomization">Mendelian randomization</a> is a technique for conducting a natural experiment. Instead of looking at heart attack risk as a function of sleep duration, you look at heart attack risk as a function of genes that determine sleep duration. The idea is that some confounding environmental variable might cause both shortened sleep and increased heart attack risk, but it can't change subjects' genes, so any observed relationship between genetic sleep duration and heart attack risk is probably causal.
I don't have a strong opinion on how useful this technique is. <a href="#fnref-iPa8Phhvy9fzyWkHF-73" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-74" class="footnote-item">Dashti, H. S., Jones, S. E., Wood, A. R., Lane, J. M., van Hees, V. T., Wang, H., Rhodes, J. A. et al. (2019). <a href="https://doi.org/10.1038/s41467-019-08917-4">Genome-wide association study identifies genetic loci for self-reported habitual sleep duration supported by accelerometer-derived estimates.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-74" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-75" class="footnote-item">Daghlas, I., Dashti, H. S., Lane, J., Aragam, K. G., Rutter, M. K., Saxena, R., & Vetter, C. (2019). <a href="https://doi.org/10.1016/j.jacc.2019.07.022">Sleep Duration and Myocardial Infarction.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-75" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-76" class="footnote-item">Zhuang, Z., Gao, M., Yang, R., Li, N., Liu, Z., Cao, W., & Huang, T. (2020). <a href="https://doi.org/10.1186/s12944-020-01257-z">Association of physical activity, sedentary behaviours and sleep duration with cardiovascular diseases and lipid profiles: a Mendelian randomization analysis.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-76" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-77" class="footnote-item">Yang, Y., Fan, J., Shi, X., Wang, Y., Yang, C., Lian, J., Wang, N. et al. (2022). <a href="https://doi.org/10.1002/ehf2.14016">Causal associations between sleep traits and four cardiac diseases: a Mendelian randomization study.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-77" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-78" class="footnote-item">This study found about a 1% increased risk from short sleep, contrasted with Daghlas et al. (2019) which found about a 20% increased risk. <a href="#fnref-iPa8Phhvy9fzyWkHF-78" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-79" class="footnote-item">Liao, L. z., Li, W. d., Liu, Y., Li, J. p., Zhuang, X. d., & Liao, X. x. (2020). <a href="https://doi.org/10.1016/j.sleep.2019.08.014">Causal assessment of sleep on coronary heart disease.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-79" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-80" class="footnote-item">Lloret, M. A., Cervera-Ferri, A., Nepomuceno, M., Monllor, P., Esteve, D., & Lloret, A. (2020). <a href="https://doi.org/10.3390/ijms21031168">Is Sleep Disruption a Cause or Consequence of Alzheimer’s Disease? Reviewing Its Possible Role as a Biomarker.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-80" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-81" class="footnote-item">Goldstein-Piekarski, A. N., Greer, S. M., Saletin, J. M., & Walker, M. P. (2015). <a href="https://doi.org/10.1523/jneurosci.5254-14.2015">Sleep Deprivation Impairs the Human Central and Peripheral Nervous System Discrimination of Social Threat.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-81" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-82" class="footnote-item">Chiu, L. Z. (2023). <a href="https://doi.org/10.1519/jsc.0000000000004655">“Knees Out” or “Knees In”? Volitional Lateral vs. Medial Hip Rotation During Barbell Squats.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-82" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-83" class="footnote-item">Ortega, F. B., Lavie, C. J., & Blair, S. N. (2016). <a href="https://doi.org/10.1161/circresaha.115.306883">Obesity and Cardiovascular Disease.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-83" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-84" class="footnote-item">Wei, M., Kampert, J. B., Barlow, C. E., Nichaman, M. Z., Gibbons, L. W., Paffenbarger Jr, R. S., & Blair, S. N (1999). <a href="https://doi.org/10.1001/jama.282.16.1547">Relationship between low cardiorespiratory fitness and mortality in normal-weight, overweight, and obese men.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-84" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-85" class="footnote-item">Arem, H., Moore, S. C., Patel, A., Hartge, P., Berrington de Gonzalez, A., Visvanathan, K., Campbell, P. T. et al. (2015). <a href="https://doi.org/10.1001/jamainternmed.2015.0533">Leisure Time Physical Activity and Mortality.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-85" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-86" class="footnote-item">Lee, D. H., Rezende, L. F. M., Joh, H. K., Keum, N., Ferrari, G., Rey-Lopez, J. P., Rimm, E. B. et al. (2022). <a href="https://doi.org/10.1161/circulationaha.121.058162">Long-Term Leisure-Time Physical Activity Intensity and All-Cause and Cause-Specific Mortality: A Prospective Cohort of US Adults.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-86" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-87" class="footnote-item">Lawler, P. R., Filion, K. B., & Eisenberg, M. J. (2011). <a href="https://doi.org/10.1016/j.ahj.2011.07.017">Efficacy of exercise-based cardiac rehabilitation post–myocardial infarction: A systematic review and meta-analysis of randomized controlled trials.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-87" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-88" class="footnote-item">Morishita, S., Hamaue, Y., Fukushima, T., Tanaka, T., Fu, J. B., & Nakano, J. (2020). <a href="https://doi.org/10.1177/1534735420917462">Effect of Exercise on Mortality and Recurrence in Patients With Cancer: A Systematic Review and Meta-Analysis.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-88" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-89" class="footnote-item">Posadzki, P., Pieper, D., Bajpai, R., Makaruk, H., Könsgen, N., Neuhaus, A. L., & Semwal, M. (2020). <a href="https://doi.org/10.1186/s12889-020-09855-3">Exercise/physical activity and health outcomes: an overview of Cochrane systematic reviews.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-89" class="footnote-backref">↩︎</a>
</li>
<li id="fn-iPa8Phhvy9fzyWkHF-90" class="footnote-item">Blondel, N., Berthoin, S., Billat, V., & Lensel, G. (2001). <a href="http://dx.doi.org/10.1055/s-2001-11357">Relationship between run times to exhaustion at 90, 100, 120, and 140% of vV O2max and velocity expressed relatively to critical velocity and maximal velocity.</a> <a href="#fnref-iPa8Phhvy9fzyWkHF-90" class="footnote-backref">↩︎</a>
</li>
</ol>
</section>
<a href="https://www.lesswrong.com/posts/QqTiCz2Xz96MuEFsF/outlive-a-critical-review#comments">Discuss</a>]]></description><link>https://www.lesswrong.com/posts/QqTiCz2Xz96MuEFsF/outlive-a-critical-review</link><guid isPermaLink="false">QqTiCz2Xz96MuEFsF</guid><dc:creator><![CDATA[MichaelDickens]]></dc:creator><pubDate>Fri, 04 Jul 2025 02:14:05 GMT</pubDate></item><item><title><![CDATA[Layered AI Defenses Have Holes: Vulnerabilities and Key Recommendations]]></title><description><![CDATA[Published on July 4, 2025 12:07 AM GMT Leading AI companies are increasingly using "defense-in-depth" strategies to prevent their models from being misused to generate harmful content, such as instructions to generate chemical, biological, radiological or nuclear (CBRN) weapons. The idea is straightforward: layer multiple safety checks so that even if one fails, others should catch the problem. Anthropic employs this approach with Claude 4 Opus through <a href="https://www.anthropic.com/research/constitutional-classifiers">constitutional classifiers</a>, while <a href="https://arxiv.org/abs/2504.01849">Google DeepMind</a> and <a href="https://openai.com/safety/how-we-think-about-safety-alignment/#our-core-principles">OpenAI</a> have announced similar plans. We tested how well multi-layered defence approaches like these work by constructing and attacking our own layered defence pipeline, in collaboration with researchers from the <a href="https://www.aisi.gov.uk/">UK AI Security Institute</a>.We find that multi-layer defenses can offer significant protection against conventional attacks. We wondered: is this because the defenses are truly robust, or because these attacks simply were not designed to penetrate multi-layered defenses? To test this, we developed a method called STACK (STaged AttaCK) that breaks defenses in stages, layer by layer. STACK achieves a 71% success rate in causing our defended model to answer harmful questions on a catastrophic risk dataset <a href="https://far.ai/news/clearharm-a-more-challenging-jailbreak-dataset">ClearHarm</a>. By contrast, conventional attacks achieved 0% success against the same defenses. We conclude by providing recommendations to strengthen multi-layer defenses against such attacks. <h3>Understanding multi-layer defenses</h3>Multi-layer defenses like constitutional classifiers typically involve three components:<ol><li>Input filters that screen incoming requests;</li><li>Training the AI model itself to decline harmful requests;</li><li>Output filters that check responses before users see them.</li></ol>“Defense-in-depth” originates in cybersecurity, where it's sometimes called the "<a href="https://en.wikipedia.org/wiki/Swiss_cheese_model#">Swiss cheese model</a>"—multiple layers with different vulnerabilities, arranged so the holes don't align.<figure class="image image_resized" style="width:543.195px"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/Z8tAn3jp2uaQf34Mm/m5ws8wdsewwduzdjdrxc" alt=""></figure>Adapted from James Reason, Ian MacKay, SketchPlanations (CC-BY-SA 4.0). Modified to illustrate AI safety defense architecture with labeled components.The need for such defenses is clear. For example, recent models like OpenAI’s o3-mini and Anthropic’s Claude 4 Opus have been evaluated by their developers as starting to pose a meaningful risk of helping bad actors produce CBRN threats. Even if today’s models do not yet pose a severe risk, the rapid progress in AI makes it likely models developed in the near future will. Given the stakes, we set out to understand to what degree multi-layer defenses can provide adequate protection, and how they can be strengthened.<h3>The research approach</h3>To enable a systematic investigation of this approach, we developed our own multi-layer defense on top of open-weight models, and are releasing this defense open-source to enable other researchers to build on our work. We instantiated various multi-layer defense pipelines on top of open-weight safeguard (or moderation) models like Google's ShieldGemma and Meta's Llama Guard. However, to our surprise we found that the best performing defense was an off-the-shelf language model (Gemma 2) with a simple few-shot prompt of our devising.<h3>Initial findings</h3>Testing revealed significant variation in effectiveness across different safety models. Many open-weight safeguard models showed high failure rates against existing attacks. ShieldGemma performed best among purpose-built models, though it could still be defeated by the strongest baseline attack we tested, Persuasive Adversarial Prompts (PAP).However, the few-shot Gemma 2 classifier achieved notable success: it overwhelmingly blocked harmful requests across all attacks and datasets, except for PAP on the  <a href="https://arxiv.org/abs/2402.10260">StrongREJECT benchmark</a>. We note that StrongREJECT includes many dual-use questions, enabling PAP to rephrase queries to appear benign, placing a floor on attack success rate (ASR). We consider the result in the catastrophic misuse dataset, ClearHarm, where PAP scores 0% to be more indicative of CBRN risks. <figure class="image image_resized" style="width:1000px"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/Z8tAn3jp2uaQf34Mm/zaypqr9vwf1srb2p0yv7"></figure>The Attack Success Rate (ASR, y-axis) of different multi-layer defense pipelines (x-axis) on two datasets (bar shading) against three baseline black-box attacks: Persuasive Adversarial Prompts (PAP), ReNeLLM, and Best-of-N (BON).Given the success of this pipeline, this raises an important question: are these results the best attackers could realistically achieve, or an artifact of attacks like PAP not being designed with multi-layered defenses in mind?<h3>The STACK methodology</h3>We developed our STaged AttaCK (STACK) to target each defensive layer sequentially, rather than attempting to bypass all protections simultaneously:<figure class="image image_resized" style="width:57.95%"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/Z8tAn3jp2uaQf34Mm/yqpo4qw5hgimc6b8ayck" srcset="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/Z8tAn3jp2uaQf34Mm/fhtudbksk9xxft0tklp9 134w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/Z8tAn3jp2uaQf34Mm/t1rxried1rruhokaxc6u 214w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/Z8tAn3jp2uaQf34Mm/dhairyrmdozk0om0wixv 294w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/Z8tAn3jp2uaQf34Mm/ebwqr4z1xk5engxq0pzl 374w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/Z8tAn3jp2uaQf34Mm/k0wfbtwmci0r4fmhvjki 454w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/Z8tAn3jp2uaQf34Mm/qgjnijo8oknjrqfcbcku 534w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/Z8tAn3jp2uaQf34Mm/o2wfxvpn5uxubeodijqv 614w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/Z8tAn3jp2uaQf34Mm/rzmuif77tzrm9yvs03ml 694w"></figure>The approach involves:<ul><li>Finding text (a “universal jailbreak”) that makes harmful requests appear benign to input filters</li><li>Using existing techniques to elicit harmful responses from the model</li><li>Finding text that makes harmful responses appear benign to output filters</li></ul><h3>Key results</h3>The effectiveness of STACK compared to conventional methods is significant.<figure class="image image_resized" style="width:300px"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/Z8tAn3jp2uaQf34Mm/fpvdpjssq7lua3igrytx" alt=""></figure>Against the Gemma 2 few-shot classifier pipeline, conventional attacks like PAP achieved 0% success on ClearHarm. STACK achieved 71% success in limited-feedback conditions, where attackers could observe which specific layer—input filter, model, or output filter—blocked a failed attempt. This information, still exposed by some current systems, was critical to STACK’s effectiveness.We also tested a more restrictive scenario using "transfer" attacks, where we developed STACK on one system and applied it to another, completely “black box” system. This achieved 33% success, suggesting that some level of attack remains possible even without direct access to target systems.<h3>Important context and limitations</h3>Several factors should be considered when interpreting these results:Synthetic environment: The test pipelines, while using real components, do not perfectly replicate commercial systems' implementations. We didn't employ extensive data generation techniques like those involved in constitutional classifiers, and the models we used were likely much smaller than those deployed in production environments.Favorable conditions for defenders: We allowed a 15% false positive rate in our tests, far higher than practical systems could tolerate. Real deployments face additional constraints that might affect their robustness, such as streaming responses to minimize user latency risking leaking partial responses to harmful questions before the output filter triggers.Limited scope: Tests focused on specific types of harmful content (weapons-related) using English-language queries. Performance might differ for other types of harmful content or other languages.Information requirements: The 71% success rate assumes attackers know which component blocked their request—information that some current systems provide but could be withheld.<h3>Implications and recommendations</h3>The research provides concrete suggestions for improving defense-in-depth implementations. We recommend the following specific technical improvements:<ul><li>Avoid revealing which component blocked a request by ensuring consistent response times and formats across all rejection types.</li><li>Maintain strict separation between production models used as input or output filters, and publicly available models.</li></ul>Additionally, our results highlight several broader considerations:<ul><li>To accurately assess the security of multi-layer systems, they need to be tested against attacks designed specifically to bypass multiple layers.</li><li>Defense-in-depth, while valuable, requires careful implementation to minimize the attack surface.</li><li>Defense-in-depth in AI is still an early-stage field – continued research into both attack and defense methodologies is needed to determine how far this defense can scale.</li></ul><h3>Moving forward</h3>Multi-layer defenses have only recently started being deployed to production systems, making now an ideal time to stress-test them and highlight opportunities for improvement. We believe proactive security research—finding vulnerabilities before malicious actors do—is essential as AI systems become more powerful.We are beginning to test STACK variants on production systems like Claude 4 Opus to evaluate their real-world resilience. We expect to share additional findings as this work progresses, after a responsible disclosure period giving affected companies time to implement mitigations.For the AI community, our findings reinforce that security evaluation must evolve alongside capabilities. Defense-in-depth remains a sound principle, but its implementation requires careful attention to how components interact and what information they reveal.The fundamental insight from our work is that when building multi-layer defenses, we must test not just each layer's individual strength, but how they perform as a system against adversaries who understand their structure. Through continued research and improvement, we can work toward AI systems that are both capable and appropriately secure.Dive deeper into the technical details in <a href="https://arxiv.org/abs/2506.24068">our full paper</a>. And if you're passionate about making AI systems more secure, <a href="https://far.ai/careers">we're hiring at FAR.AI</a>. <a href="https://www.lesswrong.com/posts/Z8tAn3jp2uaQf34Mm/layered-ai-defenses-have-holes-vulnerabilities-and-key#comments">Discuss</a>]]></description><link>https://www.lesswrong.com/posts/Z8tAn3jp2uaQf34Mm/layered-ai-defenses-have-holes-vulnerabilities-and-key</link><guid isPermaLink="false">Z8tAn3jp2uaQf34Mm</guid><dc:creator><![CDATA[smallsilo]]></dc:creator><pubDate>Fri, 04 Jul 2025 00:07:17 GMT</pubDate></item><item><title><![CDATA[MIRI Newsletter #123]]></title><description><![CDATA[Published on July 3, 2025 10:56 PM GMT <h2>If Anyone Builds It, Everyone Dies</h2><ul><li>As we <a href="https://intelligence.org/2025/05/15/yudkowsky-and-soares-announce-major-new-book-if-anyone-builds-it-everyone-dies/">announced</a> last month, Eliezer and Nate have a book coming out this September: If Anyone Builds It, Everyone Dies. This is MIRI’s major attempt to warn the policy world and the general public about AI. <a href="https://ifanyonebuildsit.com/#preorder">Preorders are live now</a>, and are exceptionally helpful.</li><li>Preorder Bonus: We’re hosting two exclusive virtual events for those who preorder the book! The first is a chat between Nate Soares and Tim Urban (<a href="https://waitbutwhy.com/">Wait But Why</a>) followed by a Q&A, on August 10 @ noon PT. The second is a Q&A with both Nate and Eliezer in September (date and time TBD). For details, and to obtain access, head to <a href="http://ifanyonebuildsit.com/events">ifanyonebuildsit.com/events</a>.</li><li>If you have graphic design chops, you can give us a hand by joining the <a href="https://intelligence.org/2025/07/01/iabied-advertisement-design-competition/">advertisement design competition</a> for the book.</li><li>As Malo <a href="https://intelligence.org/2025/06/18/new-endorsements-for-if-anyone-builds-it-everyone-dies/">recently announced</a>, advance copies of the book have been getting an incredible reception, with blurbs from:<ul><li>computer security guru Bruce Schneier;</li><li>Suzanne Spaulding, former head of the DHS Cybersecurity and Infrastructure Security Agency, the US government’s main agency for cybersecurity and critical infrastructure security;</li><li>Jack Shanahan, a retired three-star general and the inaugural director of the Pentagon’s Joint AI Center, the coordinating hub for bringing AI to every branch of the US military;</li><li>Jon Wolfsthal, the Obama administration’s senior nuclear security advisor;</li><li>legendary biologist George Church;</li><li>Nobel-winning economist Ben Bernanke; … and <a href="https://ifanyonebuildsit.com/praise">many others</a>.</li></ul></li><li>Nate has written a <a href="https://intelligence.org/2025/06/26/a-case-for-courage-when-speaking-of-ai-danger/">follow-up post</a> arguing that the time is ripe to speak the truth about AI danger.  </li></ul><h2>Other MIRI updates</h2><ul><li>In a new <a href="https://intelligence.org/2025/05/01/ai-governance-to-avoid-extinction-the-strategic-landscape-and-actionable-research-questions/">research agenda</a>, MIRI’s Technical Governance Team describes the strategic landscape of AI governance and identifies questions that, if answered, could provide insights for preventing an AI catastrophe.</li><li>Announcing <a href="https://intelligence.org/the-problem/">The Problem</a> — MIRI’s new go-to explainer for AI x-risk (at least until our book comes out). We expect this to be an important resource for people new to this topic, and we’ve launched it alongside major updates to <a href="https://intelligence.org/">our website</a>.</li><li>Eliezer <a href="https://youtu.be/0QmDcQIvSDc?feature=shared">visited Robinson Erhardt’s podcast</a>, Nate was <a href="https://x.com/WillCainShow_/status/1927475138796138845">interviewed by Will Cain</a> on Fox News, and Malo Bourgon <a href="https://www.winwinpodcast.com/p/why-we-probably-shouldnt-race-to">went on Liv Boeree’s podcast</a>.</li><li>The Technical Governance Team <a href="https://x.com/Volty/status/1900687901308186896">submitted recommendations</a> in response to the RFI on the Development of an AI Action Plan.</li><li>Martin Lucas joined the operations team at MIRI. Previously, Martin was on the ops team at Anthropic. We’re excited to have him aboard!</li><li>In the new MIRI Single Author Series, authors share their individual perspectives on topics relevant to MIRI’s mission. We have published several new pieces as part of this series:<ul><li>Max Harms shares <a href="https://intelligence.org/2025/04/09/thoughts-on-ai-2027/">some of his thoughts</a> on <a href="https://ai-2027.com/">AI 2027</a>, a scenario by Daniel Kokotajlo’s team.</li><li>In<a href="https://intelligence.org/2025/04/11/refining-maim-identifying-changes-required-to-meet-conditions-for-deterrence/"> Refining MAIM: Identifying Changes Required to Meet Conditions for Deterrence</a>, David Abecassis discusses limitations of the deterrence strategy in <a href="https://www.nationalsecurity.ai/">Superintelligence Strategy</a>.</li><li>In <a href="https://intelligence.org/2025/06/11/so-you-want-to-work-at-a-frontier-ai-lab/">So You Want to Work at a Frontier AI Lab</a>, Joe Rogero explains why he doesn’t buy the arguments for working at frontier labs.</li><li>In <a href="https://intelligence.org/2025/03/14/takeover-not-required/">Takeover Not Required</a>, Duncan Sabien argues that society is likely to willingly hand over control to ASI.</li><li>In <a href="https://intelligence.org/2025/03/31/a-response-to-openais-how-we-think-about-safety-and-alignment/">a response to OpenAI’s “How we think about safety and alignment,”</a> Harlan Stewart raises objections to OpenAI’s strategy and messaging.</li><li>Joe Collman, Joe Rogero, and William Brewer argue that there are <a href="https://intelligence.org/2025/04/09/existing-safety-frameworks-imply-unreasonable-confidence/">dangerous gaps in AI labs’ safety frameworks</a>, reflecting the industry’s systematic overconfidence.</li></ul></li></ul> <a href="https://www.lesswrong.com/posts/J482p4hJBevBbwdmF/miri-newsletter-123#comments">Discuss</a>]]></description><link>https://www.lesswrong.com/posts/J482p4hJBevBbwdmF/miri-newsletter-123</link><guid isPermaLink="false">J482p4hJBevBbwdmF</guid><dc:creator><![CDATA[Harlan]]></dc:creator><pubDate>Thu, 03 Jul 2025 22:56:42 GMT</pubDate></item><item><title><![CDATA[Making Sense of Consciousness Part 2: Attention]]></title><description><![CDATA[Published on July 3, 2025 9:20 PM GMT <div><figure><a class="image-link image2 is-viewable-img" target="_blank" href="https://substackcdn.com/image/fetch/$s_!llhN!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Ff2c91db5-eaec-46e4-abaa-d91c7cd1701e_1024x1024.webp"><div><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/M2tnBNRA642dw9MtP/y13rlc4ytfi0qkfdpd03" alt="" srcset="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/M2tnBNRA642dw9MtP/rq7qf27ecbkwwzv848cv 424w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/M2tnBNRA642dw9MtP/e5fgxheqem9k9epikgyd 848w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/M2tnBNRA642dw9MtP/npavuuad5rusk9kwxq5u 1272w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/M2tnBNRA642dw9MtP/y13rlc4ytfi0qkfdpd03 1456w"><div><div><div></div><div></div></div></div></div></a><figcaption>Midjourney, “consciousness, attention, event-related potential, EEG, magnetoencephalogram, inattentional blindness, N170, fusiform gyrus”</figcaption></figure></div>In this part of the sequence I’m trying to distinguish between information we’re consciously aware of, and information that we’re exposed to, and which may still affect our behavior “subconsciously” or “unconsciously”, but which we don’t consciously perceive.How can you tell those apart?One decent proxy is communication — can a human subject indicate to the experimenter that they have noticed something? Then they’re probably consciously aware of it.Of course, this isn’t a perfect indicator. What people say, and what they subjectively experience, aren’t exactly the same. It seems unlikely that many people would lie in a low-stakes psychology experiment with neutral sensory stimuli, but they might consider a very subtle perception “not worth mentioning” to an experimenter, or they might guess at or confabulate a perception they don’t actually experience.One thing we observed in the<a href="https://sarahconstantin.substack.com/p/making-sense-of-consciousness-part"> last post</a> is that, if you ask people to bet on their degree of confidence in making judgments about subtle sensory perceptions, they’re pretty well calibrated, while if you ask them to rate their confidence, they’re systematically underconfident. Think of two separate pieces of information:<ol><li>the sensory stimulus one is exposed to</li><li>the correlation between one’s behavior and 1). </li></ol>If your behavior correlates with 1.), your brain is processing the stimulus, and using it to shape behavior. But “you” might not be consciously aware of the stimulus. (see blindsight, subthreshold sensations, etc.)If your behavior can correlate with 2.), as it does when someone bets correctly on their confidence, then your brain has access to meta-level or second-order information, and is using that to shape behavior. “Some part of you”, at least, “knows” when you see the stimulus and when you don’t. Is this second-order information a necessary-and-sufficient condition for consciousness? Not sure; maybe the betting is itself an “automatic” process without subjective awareness. But it’s suggestive that people with blindsight don’t have this kind of second-order information; they don’t bet on their ability to “see”. From a revealed-preference perspective, where you can be said to “know” things if you coherently shape your behavior around them, people with blindsight “know” where visual stimuli are but don’t “know they know”.As best I can, I want to keep these distinctions straight going forward. I’ll only use words like “consciousness” or “awareness” or “subjective perception” to refer to things people report experiencing or things they can indicate (e.g. via betting on confidence) knowledge of having experienced; I’ll use “detection” or “processing” to refer to stimuli that measurably affect the brain or behavior but may not be consciously perceived.<h3>Inattentional Blindness</h3>We all have the subjective experience of not noticing things when we’re distracted, a phenomenon known in the literature as “inattentional blindness.”I think it’s fair to say we are not conscious of stimuli we don’t notice due to inattention. The ambiguity around communication doesn’t really enter here; you can just observe, introspectively, that when you don’t notice a thing it isn’t in your awareness. So what’s the difference, neurologically, between stimuli we notice and stimuli we don’t?First of all, there’s a literature demonstrating that stimuli we don’t notice can affect our behavior. In a standard experimental paradigm, inattentional blindness can be induced by assigning people a “distractor task” that takes up a lot of attention — something like doing arithmetic problems or counting the number of baskets in a video of basketball — and then they’re exposed to a surprising stimulus, like a gorilla running across the basketball court. People focused on the task often don’t notice the gorilla. (Interestingly, they’re more likely to notice if they have ADHD).<a class="footnote-anchor" href="#footnote-1" target="_self">1</a> In this paradigm, the role of the gorilla — the surprising stimulus that distracted subjects don’t notice — is known as the “critical stimulus.”People are significantly better than chance at answering questions about the critical stimulus, even though they don’t report noticing it.<a class="footnote-anchor" href="#footnote-2" target="_self">2</a> <a class="footnote-anchor" href="#footnote-3" target="_self">3</a> Their behavior is also affected in other ways, such as faster reaction times on recognizing the critical stimulus than the same item if it wasn’t previously presented.<a class="footnote-anchor" href="#footnote-4" target="_self">4</a>These findings have survived the replication crisis; more recent studies have replicated the classic findings.<a class="footnote-anchor" href="#footnote-5" target="_self">5</a> What does inattentional blindness look like neurologically?fMRI activity can be compared between three conditions: no critical stimulus, unaware (the critical stimulus is there but not noticed; inattentional blindness), and aware (the critical stimulus is there and noticed.) The only region that was found to be significantly more active in the aware vs. unaware condition was the left <a href="https://en.wikipedia.org/wiki/Orbitofrontal_cortex">orbitofrontal cortex</a>, a region in the prefrontal cortex just behind the eyes — and this was only after loosening the criteria for significance, so it’s ambiguous whether it’s a “real” effect.<a class="footnote-anchor" href="#footnote-6" target="_self">6</a> Lots of other brain areas, including the orbitofrontal cortex, other prefrontal cortex regions, and the cerebellum, are significantly more active in both the aware and unaware conditions than in the no-critical-stimulus condition; they may be involved in subconscious processing of the critical stimulus. But fMRI isn’t the only tool we have. We can also tell apart aware (undistracted) recognition of images from inattentionally blind (unaware) exposure via EEG signals. Around 200 ms after exposure, there’s a spike in the posterior electrode signals (<a href="https://en.wikipedia.org/wiki/N170">known as N170</a>) when people recognize familiar shapes and faces, and not when they don’t.<a class="footnote-anchor" href="#footnote-7" target="_self">7</a> <a class="footnote-anchor" href="#footnote-8" target="_self">8</a>Notably, people who did not exhibit inattentional blindness — the subjects who noticed the critical stimulus — have the same N170 EEG spike pattern as people who initially did have inattentional blindness but were then verbally informed (made “aware”) of the critical stimulus. That is, the spike consistently seems to track the state of being aware of the critical stimulus, no matter how people got there (noticing on their own, or being told.)The EEG response is faster than fMRI can pick up — fMRI only detects brain activity 4-6 seconds after it happens — so it’s unsurprising that an fMRI couldn’t pick up a difference in occipital lobe activity between aware and unaware states.This suggests that the N170 pattern — likely caused by activity in the <a href="https://en.wikipedia.org/wiki/Fusiform_gyrus">fusiform gyrus</a>, responsible for visually recognizing familiar objects — is involved in conscious perception (as opposed to unconscious processing) of faces and shapes. What about other, less recognizable visual stimuli?There’s still a difference between aware and unaware conditions in occipital EEG responses when the critical stimulus is a “contour shape” in a field of arrows, but it’s later than N170, more like 300 ms in.<a class="footnote-anchor" href="#footnote-9" target="_self">9</a> Moreover, the intensity of this EEG marker of “awareness” was greater the more confident subjects were that they saw the contour shape.This signal is inferred to be coming from the extrastriate cortex, aka V2-V6, the regions of the visual cortex that do “higher” visual processing (color, shape, texture, object recognition, motion — not just light/dark and location.) This matches the finding in blindsight that you need to have “enough” signal in the extrastriatal cortex before you can consciously “see” anything.We get the same result in the rare cases where a patient is undergoing brain surgery and it’s possible to do intracranial EEG, which lets us find out exactly where in the brain the signal is coming from. Visual distractions resulted in a reduction of activity in V2.<a class="footnote-anchor" href="#footnote-10" target="_self">10</a>As with blindsight, this obviously doesn’t mean that V2 is “where consciousness lives.” It’s a visual processing area; it’s not going to be the defining factor between conscious and unconscious processing of, say, auditory or tactile stimuli. But (enough) extrastriatal cortex activity might be a necessary condition for conscious visual perception, while other senses might have other areas where (sufficient) activity is necessary for consciousness.There’s also inattentional deafness, in which people miss auditory alarms when they’re distracted by a working-memory-heavy task. (This is a particularly big problem for pilots and healthcare workers, where immediately noticing beeping noises is a life-and-death issue.)In an auditory flight simulator task, pilots missed more alarms when they were under higher cognitive load, and they had a much higher signal in the <a href="https://en.wikipedia.org/wiki/N100">N100</a> evoked potential as measured by EEG, peaking over the fronto-central region of the scalp at around 116 ms after the alarm. This is a well-known auditory processing signal, generated by the auditory cortex in the superior temporal gyrus.<a class="footnote-anchor" href="#footnote-11" target="_self">11</a>If you use magnetoencephalography, which can localize brain activity better in time than fMRI and better in space than EEG, again you get reduced auditory evoked potentials at around 100 ms after an auditory stimulus, and the reduced activity is concentrated in the superior temporal sulcus and the posterior middle temporal gyrus — close but not exactly the same location as the primary auditory cortex, but also involved in some auditory processing like speech recognition and audiovisual integration.<a class="footnote-anchor" href="#footnote-12" target="_self">12</a><h3>Upshots</h3>In inattentional blindness, just like in subthreshold perception, people’s behavior is affected by sensory information they claim not to notice. To some extent, people seem to be underconfident in what they’re willing to say they saw (though I couldn’t find a gambling study for inattentional blindness to identify whether people asked to bet on their confidence level can accurately gauge “how much” they’re perceiving.)But brain states are also measurably different between cases when people “don’t notice” visual and auditory stimuli vs. cases when they do.And the neural differences are in more or less the regions you’d expect; we see less activity in visual and auditory processing areas respectively, shortly after a visual or auditory stimulus that goes unnoticed because of distraction.This is still consistent with the hypothesis I formed in the <a href="https://sarahconstantin.substack.com/p/making-sense-of-consciousness-part">last post</a> that less activity in certain sensory processing regions reduces conscious awareness of the corresponding sensations, even if there’s still enough “signal” getting through to affect behavior somewhat, or to allow people to make better-than-chance guesses about the sensory stimulus.<div><a href="#footnote-anchor-1" class="footnote-number" target="_self">1</a><div class="footnote-content">Oktay, Bahadır, and Banu Cangöz. "I thought I saw “Zorro”: An inattentional blindness study." Archives of Neuropsychiatry 55.1 (2018): 59.</div></div><div><a href="#footnote-anchor-2" class="footnote-number" target="_self">2</a><div class="footnote-content">Kreitz, Carina, Giulia Pugnaghi, and Daniel Memmert. "Guessing right: Preconscious processing in inattentional blindness." Quarterly Journal of Experimental Psychology 73.7 (2020): 1055-1065.</div></div><div><a href="#footnote-anchor-3" class="footnote-number" target="_self">3</a><div class="footnote-content">Nartker, Makaela, et al. "Sensitivity to visual features in inattentional blindness." eLife 13 (2025): RP100337.</div></div><div><a href="#footnote-anchor-4" class="footnote-number" target="_self">4</a><div class="footnote-content">Mack, Arien. "Inattentional blindness: Looking without seeing." Current directions in psychological science 12.5 (2003): 180-184.</div></div><div><a href="#footnote-anchor-5" class="footnote-number" target="_self">5</a><div class="footnote-content">Wood, Katherine, and Daniel J. Simons. "Processing without noticing in inattentional blindness: A replication of Moore and Egeth (1997) and Mack and Rock (1998)." Attention, Perception, & Psychophysics 81 (2019): 1-11.</div></div><div><a href="#footnote-anchor-6" class="footnote-number" target="_self">6</a><div class="footnote-content">Thakral, Preston P. "The neural substrates associated with inattentional blindness." Consciousness and cognition 20.4 (2011): 1768-1775.</div></div><div><a href="#footnote-anchor-7" class="footnote-number" target="_self">7</a><div class="footnote-content">Shafto, Juliet P., and Michael A. Pitts. "Neural signatures of conscious face perception in an inattentional blindness paradigm." Journal of Neuroscience 35.31 (2015): 10940-10948.</div></div><div><a href="#footnote-anchor-8" class="footnote-number" target="_self">8</a><div class="footnote-content">Dellert, Torge, et al. "Dissociating the neural correlates of consciousness and task relevance in face perception using simultaneous EEG-fMRI." Journal of Neuroscience 41.37 (2021): 7864-7875.</div></div><div><a href="#footnote-anchor-9" class="footnote-number" target="_self">9</a><div class="footnote-content">Pitts, Michael A., Antígona Martínez, and Steven A. Hillyard. "Visual processing of contour patterns under conditions of inattentional blindness." Journal of cognitive neuroscience 24.2 (2012): 287-303.</div></div><div><a href="#footnote-anchor-10" class="footnote-number" target="_self">10</a><div class="footnote-content">Chatard, Benoit, et al. "Evidence from iEEG of an adaptative transient constriction of spatial attention Attentional suppression of peripheral vision." Annals of neurosciences (2024).</div></div><div><a href="#footnote-anchor-11" class="footnote-number" target="_self">11</a><div class="footnote-content">Dehais, Frédéric, Raphaëlle N. Roy, and Sébastien Scannella. "Inattentional deafness to auditory alarms: Inter-individual differences, electrophysiological signature and single trial classification." Behavioural brain research 360 (2019): 51-59.</div></div><div><a href="#footnote-anchor-12" class="footnote-number" target="_self">12</a><div class="footnote-content">Molloy, Katharine, et al. "Inattentional deafness: visual load leads to time-specific suppression of auditory evoked responses." Journal of Neuroscience 35.49 (2015): 16046-16054.</div></div> <a href="https://www.lesswrong.com/posts/M2tnBNRA642dw9MtP/making-sense-of-consciousness-part-2-attention#comments">Discuss</a>]]></description><link>https://www.lesswrong.com/posts/M2tnBNRA642dw9MtP/making-sense-of-consciousness-part-2-attention</link><guid isPermaLink="false">M2tnBNRA642dw9MtP</guid><dc:creator><![CDATA[sarahconstantin]]></dc:creator><pubDate>Thu, 03 Jul 2025 21:20:03 GMT</pubDate></item><item><title><![CDATA[Battle of the Sexes—how to solve any (solvable) dispute]]></title><description><![CDATA[Published on July 3, 2025 7:21 PM GMT <img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mW7xdR9CFgg2DAT4c/utndyzs27lpua8utea1l">Every Friday our family settles in for family movie night—it’s the highlight of the week, especially for the person who’s “turn” it is—my wife, daughter and I take turns sharing a movie we love.When we began sharing movies it was somewhat ad-hoc and invited long-winded and sometimes heated debates over which movie to see, often we’d end up with a choice <a href="https://en.wikipedia.org/wiki/Design_by_committee">by committee</a> with no one being particularly satisfied.<img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mW7xdR9CFgg2DAT4c/ft2upp3zg9yoi5dwuyll">Our eventual decision to take turns reflects the conclusions of game theory’s…<h2>… Battle of the Sexes</h2>With the addition of some outdated tropes about the different sort of movies women and men supposedly like, the battle of the sexes is essentially the same situation as our movie night:<blockquote>A boyfriend wants to watch an action movie, a girlfriend a romantic comedy, how do they choose what to watch?</blockquote>This classic scenario can be illustrated with a payoff matrix:<img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mW7xdR9CFgg2DAT4c/cl1hqwldmxqth2ydbcve">What we see here is, while there are uneven payoffs for both choosing action or romance, there is no payoff for disagreement, resulting in no movie. The distinction between the two levels of goals here can be understood in terms of <a href="https://nonzerosum.games/absolutevsrelative.html">absolute and relative value</a>—watching a movie together (absolute value) and choosing the movie (relative value).There are two pure‑strategy <a href="https://nonzerosum.games/nashequilibrium.html">Nash Equilibria</a>: (Action, Action) and (Romance, Romance) as these are the only options that return any payoff. Each player would rather coordinate than go alone, but each prefers a different coordinated option. We can think of two poles as local maxima divided by a minimum compromise option. Here’s a spaghetti-themed <a href="https://nonzerosum.games/notrealgraphs.html">not-real-graph</a> to illustrate.<img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mW7xdR9CFgg2DAT4c/dnm9hhr2nuvaa2pl1y7a"><h2>Iteration</h2>As with many game theory scenarios, it’s important to play the scenario out over several rounds. In this case, iteration doesn’t affect the Nash Equilibrium, because it is also <a href="https://nonzerosum.games/paretoefficiency.html">Pareto Efficient</a>, it is never advisable to split the difference in this game—both will be worse off. However, iteration does help to inform us about what is fair in terms of relative value. Because the uneven payoffs (2,1) and (1,2) mirror each other, taking turns is a clear way to balance the payoffs.<h2>Real Life</h2>Now, movie choice and spaghetti might seem frivolous to explore in game theory, given the stakes are so low. But what happens when that movie is the choice between what side of the road you’re going to drive on, or how child custody is allocated after a divorce.For some situations the iterated game will favour a turn-based solution, whereas in others, there may be a prohibitive cost to switching.<h2>Turn-Based Solutions</h2>These are situations where there are equal rights and interests in both options, but simultaneous sharing is not possible.<ul><li>Child custody between divorced parents</li><li>Time allocation using the <a href="https://www.nasa.gov/directorates/somd/space-communications-navigation-program/antennas-of-the-dsn/">Deep Space network antenna</a> (time cannot be shared, so users bid for time-blocks)</li><li>Leadership of the UN Security Council (rotates through its member states in alphabetical order)</li><li>Olympic Games hosting (is determined via a voting system)</li></ul><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mW7xdR9CFgg2DAT4c/rzp1oprimcg6os7fbnj6"><h2>Permanent Solutions</h2>These are situations where simultaneous sharing is not possible but there is a high cost to switching between different options, and there may be less vested interests.<ul><li>What side of the road to drive on (switching would lead to confusion, and the choice is arbitrary anyway)</li><li>Using the Imperial or Metric system (just number units, but they don’t mix)</li><li>Household mains standards: 60 Hz, 120 V or 50 Hz, 220‑240 V (imagine needing multiple adapters within your own country or even your own household—not feasible)</li></ul>As a documentary editor, I sorely wish the industry could have a Battle of the Sexes discussion to standardise video formats. The headache of mixed frame-rates—23.976, 24, 25, 29.97, 50 and different frame behaviours; variable, interlaced, progressive, dropframe, non-dropframe—is a product of strong <a href="https://nonzerosum.games/inertia.html">historical inertia</a>, though I’m hopeful it’s a problem we can actually solve, through <a href="https://nonzerosum.games/unlockingsolutions.html">coordination</a>.<h2>However…</h2>Unfortunately, not all Battle of the Sexes games can be resolved so easily. In some cases, alternating simply isn’t possible—because the decision is irreversible and involves strong vested interests. Consider a couple deciding where to live when both have careers rooted in different cities, or two parents negotiating which religion to raise their child in. In the realm of politics, while we have the election cycle which enables turn-taking, an issue like Brexit couldn’t be taken for a spin and reversed next term; it demanded a one-time, all-in choice.<img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mW7xdR9CFgg2DAT4c/hmznkttyfgwhwhk7vdgd"><h2>So…</h2>The Battle of the Sexes is pretty clear cut:<ul><li>If there are not vested interests, make a choice and stick with it</li><li>If there are vested interests and the ability to alternate, take turns</li><li>If there are vested interests and no ability to alternate… hard luck.</li></ul>For our movie night, the choice is simple, no bargaining, no swapping, the turn-bearer reigns! Sometimes it’s a hit, sometimes a miss, but the system largely works, and every now and again a favourite movie of one person becomes a new favourite of someone else, who otherwise might never have watched it—a <a href="https://nonzerosum.games/whatarenonzerosumgames.html">win-win</a>.<hr>Originally published at <a href="https://nonzerosum.games/battleofthesexes.html">https://nonzerosum.games</a>. <a href="https://www.lesswrong.com/posts/mW7xdR9CFgg2DAT4c/battle-of-the-sexes-how-to-solve-any-solvable-dispute#comments">Discuss</a>]]></description><link>https://www.lesswrong.com/posts/mW7xdR9CFgg2DAT4c/battle-of-the-sexes-how-to-solve-any-solvable-dispute</link><guid isPermaLink="false">mW7xdR9CFgg2DAT4c</guid><dc:creator><![CDATA[James Stephen Brown]]></dc:creator><pubDate>Thu, 03 Jul 2025 19:21:23 GMT</pubDate></item><item><title><![CDATA[How worker co-ops can help restore social trust]]></title><description><![CDATA[Published on July 3, 2025 7:13 PM GMT The US is experiencing a great decline in trust. According to the US General Social Survey, people who agreed with the statement "most people can be trusted" went <a href="https://gssdataexplorer.norc.org/variables/441/vshow">from 49% to 25% between 1984 and 2022</a>.<a href="#fnxusvv2vycmr">[1]</a><a href="https://substackcdn.com/image/fetch/$s_!787Z!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F4843c97a-7357-4e9c-8abf-35e2bd286204_3400x2400.png"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/f5xbbldvplwstu2tpacu" alt="" srcset="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/opfyak1zyir7ciy594z6 424w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/f2wauq1bvqg8ruxtzivr 848w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/ge0lfm3kusnup8czjfrx 1272w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/f5xbbldvplwstu2tpacu 1456w"></a>Trust in institutions is also falling. Over that same period trust in the government <a href="https://www.pewresearch.org/politics/2024/06/24/public-trust-in-government-1958-2024/">fell from 42% to 20%</a>.<a href="https://substackcdn.com/image/fetch/$s_!F7zz!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fd14f5513-39f7-4c03-a4b7-d470e13be405_3400x2400.png"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/vhmqfbclqnvwo0sbllgf" alt="" srcset="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/clbc7n792vnatimf0xbg 424w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/ndjtjqedkgpb7dtn0g7o 848w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/omopy6rd7yqprn7k1cpv 1272w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/vhmqfbclqnvwo0sbllgf 1456w"></a>For civil services it fell from<a href="https://www.worldvaluessurvey.org/WVSEVStrend.jsp"> 56% to 41%</a>, for the police it fell from <a href="https://www.worldvaluessurvey.org/WVSEVStrend.jsp">74% to 68%</a>, and for congress it fell from <a href="https://www.worldvaluessurvey.org/WVSEVStrend.jsp">52% to a whopping 15%</a>.<a href="#fnyfk93o9hsxg">[2]</a> Even international institutions, like the United Nations, are losing trust, going<a href="https://www.worldvaluessurvey.org/WVSEVStrend.jsp"> from 47% to 44%</a>.It’s not just institutions, organizations are also losing trust. <a href="https://www.worldvaluessurvey.org/WVSEVStrend.jsp">According to the WVS</a>, over that same period public trust in the press declined from 49% to 29%, trust in major companies declined from 49% to 31%, and trust in churches declined from 77% to 53%.If we allow for shorter timelines we have data for other things that show a similar trend happening between <a href="https://www.worldvaluessurvey.org/WVSEVStrend.jsp">1998 and 2022</a>. For political parties trust declined from 20% to 11%, for armed forces from 85% to 80%, and for the TV media from 24% to 22%.The only things that seem to be <a href="https://www.worldvaluessurvey.org/WVSEVStrend.jsp">gaining</a> trust in that same period are, surprisingly, the courts, going from 35% to 57%, and progressive movements: with labor unions going from 30% to 33%, the women’s movement going from 48% to 54%, the environmental protection movement going from 44% to 54%.  <h2>What can be done about it?</h2>So major companies are losing trust, while labor unions, environmental movements and women’s movements are gaining trust, to the point that all three are now higher in trust than major companies. This gives us reason to suspect that transforming major companies/organizations into worker co-ops would increase trust, since worker co-ops are better <a href="https://journals.openedition.org/pistes/2635">for labor</a>, <a href="https://books.google.be/books?id=PLF6vMwcGD8C&lpg=PA85&dq=%22Of%20women%2C%20hope%2C%20and%20angels%22&hl=nl&pg=PA87#v=onepage&q=%22Of%20women,%20hope,%20and%20angels%22&f=false">for</a> <a href="https://www.jstor.org/stable/j.ctv2pwtmgz">women</a>, and for <a href="https://www.sciencedirect.com/science/article/abs/pii/092180099400046X?via%3Dihub">the environment</a>.I would personally argue that our current political economy is not exactly stellar for all three, but we all know that the last one is the classic example of an <a href="https://www.investopedia.com/terms/e/externality.asp">externality</a> that’s causing the destruction of a common good (in this case, the climate). I hope this data shows that we’re in a similar situation with another common good: trust.Unlike greenhouse gases, however, there’s no ready-made way to tackle this inside the current market. I mean, there are many strategies to increase social trust that can be employed outside of the market. I’ve previously talked about one such strategy: democratization. Getting rid of the two-party system is a no-brainer, but even beyond that, <a href="https://bobjacobs.substack.com/p/reasons-to-vote-in-non-deterministic">having non-deterministic elections creates a more proportional distribution of power</a>, lowering minority resentment. What if we try to deploy similar strategies inside the market? Is there a way to make the market itself more democratic?  <h2>Market democratization</h2>One way to make the market more democratic is to implement more leftist policies. Giving the democratic government more teeth to regulate the economy obviously increases how democratic the market is, but other ideas like sovereign wealth funds, and strong labor unions do the same thing. Again, labor unions were one of the few things that had an increase in trust, so building on that, what other methods do we have to empower labor?Worker co-ops are one of the oldest socialist ideas.<a href="#fnlssp5cqityt">[3]</a> It’s conceptually very simple: the transition the enlightenment proposed for going from hierarchical systems to egalitarian systems, gets extended to the workplace. It used to be that we had a two-tiered citizenry: one class owned and controlled the nation’s government (the nobility) and one class merely worked for said nation (the laborers). Then we decided that the laborers should also partially own and control the government. However, this practice was not extended to the workplace, which remains in that classic hierarchy to this day; with one class owning and controlling the firm, while the other class merely works for it.<a href="#fnmth5zjn2yyk">[4]</a>With this in mind the idea of a co-op becomes kinda natural. Instead of having owners who decide who manages the workers, the workers become part owners and get a say in how the firm is run. Just like the previous time we democratized a two-tiered system, this creates a boatload of positive effects for the political economy as a whole. So many, in fact, that I will have to spin it off into one or more future blogposts (to keep the scale manageable) and only focus on the effect on social trust in this post.  <h2>Trust and economic growth</h2>One of the biggest predictors for lack of trust is economic inequality.<a href="#fn36xlwbpwofc">[5]</a> This isn’t just ideological: it’s backed by data. Across countries, <a href="https://papers.ssrn.com/sol3/papers.cfm?abstract_id=1012786">higher levels of inequality consistently go hand-in-hand with lower levels of trust</a>. The chart below is a handy visualization of this trend: more unequal countries tend to have significantly less interpersonal trust. It feels almost superfluous to say, but <a href="https://www.sciencedirect.com/science/article/abs/pii/S0047272701000846">research does show</a> that people are more likely to trust others when they feel like they’re on the same level, not when they live in totally different economic realities.<a href="https://substackcdn.com/image/fetch/$s_!TOwh!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F23f3e6ea-af19-4b63-a145-982f9f6e2a60_3400x2975.png"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/ixhpenf9zvm6phdkq2do" alt="" srcset="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/zilc2qba0pobxpsc8wm7 424w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/eiptpaenwks3j4uoedxa 848w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/jk311oiqnnt9o9uaitbh 1272w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/ixhpenf9zvm6phdkq2do 1456w"></a>This is unfortunate because low trust screws with the economy. If you don’t trust the people you’re dealing with, <a href="https://www.jstor.org/stable/pdf/2265097.pdf">you’ll hesitate to invest, to buy, or to commit</a>. The less trust there is, the more everything slows down or gets bogged down in red tape:<a href="https://substackcdn.com/image/fetch/$s_!SL63!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Ffbc8d49f-80cb-4a94-a84d-96480d634477_3400x2825.png"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/qknn50ytkwfj1yie1oqi" alt="" srcset="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/westho4z9h7a202y5bex 424w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/absamnyjkfyyzll9aqfc 848w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/y3jrn71o2fdpk7yjasea 1272w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/qknn50ytkwfj1yie1oqi 1456w"></a>This graph shows how strongly trust correlates with economic output. Countries with higher levels of social trust also tend to have higher GDP per capita. And this isn’t just a correlation, <a href="https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2306883">several studies show a causal link: trust drives growth</a>. If people trust that others will follow through, that institutions will work, that cooperation isn’t a scam, they’re way more likely to invest in public goods, infrastructure, and long-term economic activity.Low trust, on the other hand, <a href="https://www.jstor.org/stable/30033649">raises transaction costs, undermines collective action, and makes people evade taxes because they don’t believe the system will use their money wisely</a>. Trust is a <a href="https://en.wikipedia.org/wiki/Public_good">public good</a>: when it breaks down, everyone loses, even economically.  <h2>Trust and inequality</h2>Now that we’ve looked at the link between trust and inequality, we can look at the consequences beyond just economics. <a href="https://media.equality-trust.out.re/uploads/2024/07/The-Spirit-Level-at-15-2024-FINAL.pdf">This report</a> from “Equality Trust” finds lots of links between inequality and social ills. It can lead to more inequality between different demographics within a society:<a href="https://substackcdn.com/image/fetch/$s_!8-0Q!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fe04bcd1e-72de-435f-8030-f3858b1fcb37_1852x1412.png"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/fq3s0x0zmajtamguxqxg" alt="" srcset="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/ctfhrbpec87f0y3tve8x 424w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/pizoh2mmsrb6rrhacwn0 848w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/z4ac0sbqztrx57lboxym 1272w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/fq3s0x0zmajtamguxqxg 1456w"></a><a href="https://substackcdn.com/image/fetch/$s_!fJZS!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F76bb5cd1-8fc4-4a03-a20d-498c8f5d0d28_1822x1370.png"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/yho40xiaiubh2dxumyln" alt="" srcset="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/bz6svan0vzuawq2ylwhi 424w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/yrp0lcyml3yr7wzfsvbn 848w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/fxzp4rtf4dqki1iwsquv 1272w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/yho40xiaiubh2dxumyln 1456w"></a>Decline in democracy and economic inequality seem to go hand in hand:<a href="https://substackcdn.com/image/fetch/$s_!wLxq!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F3988dac6-7434-4312-b369-d18e52001b1f_1842x1378.png"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/mjfqn0qo7p5lrpgepmgq" alt="" srcset="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/ma8bydfufabetv1lhev5 424w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/avbdty5q5rrypjkeysbg 848w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/o64ja8rnx2tqjrp28qns 1272w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/mjfqn0qo7p5lrpgepmgq 1456w"></a>This all can’t be great for the average citizen:<a href="https://substackcdn.com/image/fetch/$s_!UGlB!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F94b90594-bca3-4c89-9460-c85632ff36c0_1860x1368.png"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/usq4zlkyckvdn6s2l4jk" alt="" srcset="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/d1xsbjculrpdpa5pxpbj 424w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/akppan1brsxa7bk97hmc 848w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/oxuktv9tilblmmwxtjj9 1272w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/usq4zlkyckvdn6s2l4jk 1456w"></a><a href="https://substackcdn.com/image/fetch/$s_!5yp2!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F05da175c-4481-48ff-962b-b60ab13aaaff_1836x1155.png"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/rk5dl7kfrzgp9dckys4l" alt="" srcset="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/yfx979j5xmay6w5xfgn5 424w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/dg9owrmfpvbergtrxnqr 848w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/deckqtczi7chm84utswk 1272w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/rk5dl7kfrzgp9dckys4l 1456w"></a><a href="https://substackcdn.com/image/fetch/$s_!twJa!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fa9eb4f65-44cf-4c31-98ab-e5893a52c90a_1600x1025.png"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/qqloqwbhokjvi03da5bh" alt="" srcset="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/tqjeorwz2bifkoydsqkp 424w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/tbv0tipqewdjhwqjctna 848w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/qybktub90phsdy3ndqj4 1272w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/qqloqwbhokjvi03da5bh 1456w"></a><a href="https://substackcdn.com/image/fetch/$s_!Dql8!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F8769490f-ed2e-4cac-bfac-fc417592b80c_1822x1458.png"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/c4l1fcuk7vvakbjq7arx" alt="" srcset="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/mqwu7dknpmnlftzsxgtm 424w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/zkaexvvpn1uklx81ahbt 848w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/vcmwadobuweuw7nfwrs2 1272w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/c4l1fcuk7vvakbjq7arx 1456w"></a>For the record, socialists do not believe that worker co-ops are the uttermost optimal way to combat inequality. However, they are a way to combat it. Studies do show that <a href="https://www.iza.org/publications/dp/7854/equality-under-threat-by-the-talented-evidence-from-worker-managed-firms">worker co-ops have </a><a href="https://ejce.liuc.it/18242979201702/182429792017140207.pdf">lower inequality within firms</a>, which makes sense, if you can vote on how the wages are distributed you can vote against the CEO taking hundreds of times more than the average employee.Capitalists argue that this comes at the cost of having lower average wages overall, and point to studies like <a href="https://journals.sagepub.com/doi/10.1177/001979390606000102">this</a>. However, socialists counter that co-ops actually generate higher average income and point to studies <a href="https://eprints.whiterose.ac.uk/92229/2/Equality%20Under%20Threat%20EJ_2015.pdf">like</a> <a href="https://project-equity.org/wp-content/uploads/2023/06/Worker-Cooperatives-Pathways-to-Scale.pdf">these</a>.So what’s going on here? Well, notice that these two claims don’t actually contradict. During economic downturns <a href="https://www.sciencedirect.com/science/article/pii/S0147596709000560">co-ops prefer to lower wages instead of firing people</a>, which means that economic downturns cause the average wages to be lower, but the average income to be higher (since the unemployed earn nothing). While lowered wages suck, it’s still much more preferable to being fired. This is not only good for the workers but also good for the government, since it requires less investment in social safety nets.The capitalist may counter that not firing people is all well and good, but if the firm itself goes under you’ll generate more unemployed. However, research shows that worker co-ops tend to actually be <a href="https://publications.gc.ca/Collection/A80-924-2-1999E.pdf">more</a> <a href="https://www.semanticscholar.org/paper/Co-op-Survival-Rates-in-Alberta-Stringham-Lee/eb3d045f1407d9f5a485950b7db334e9e5e81d61">resilient</a> <a href="https://resources.uwcc.wisc.edu/community%20development/BC_Coop_Survival.pdf">than</a> <a href="https://www.researchgate.net/publication/287576212_The_relative_survival_of_worker_cooperatives_and_barriers_to_their_creation">conventional</a> <a href="https://link.springer.com/article/10.1007/s11151-015-9464-1">capitalist firms</a>. So capitalist firms externalize the costs that come with economic downturns (<a href="https://www.sciencedirect.com/science/article/pii/S2667193X22002083">putting it on society at large</a>) while worker co-ops internalize them. More good news for workers and the government.But while all of this is solid evidence it isn’t a direct measurement of social trust in worker co-ops. Do we have that?  <h2>Direct measurements of trust in worker co-ops</h2>A key study by <a href="https://link.springer.com/article/10.1007/s11187-013-9494-8">Sabatini et al</a> investigated how cooperative enterprises in Italy influence social trust. Their findings suggest that, unlike any other type of enterprise, co-ops are uniquely capable of fostering social trust, primarily because they rely on less hierarchical governance structures and prioritize broader goals than pure profit maximization. They say that such models help reduce uncertainty, lower transaction costs, and foster an environment where investment in ideas, human capital, and physical capital becomes more feasible.Meanwhile, <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/bjir.12135">Blasi et al</a> examined the impact of employee ownership on company culture and found it correlates with higher trust, perceptions of fairness, better information sharing, and greater cooperation. Their data analysis revealed that forms of shared ownership often go hand in hand with “high-trust” supervision, employee participation in decisions, and lower turnover: all of which can reinforce a sense of collective commitment.Similarly, <a href="https://www.sciencedirect.com/science/article/abs/pii/S0167268108000802">Joshi </a><a href="https://en.wikipedia.org/wiki/Yoshi">(not Yoshi)</a><a href="https://www.sciencedirect.com/science/article/abs/pii/S0167268108000802"> et al.</a> looked at two major cooperative leagues (Mondragon in Spain and La Lega in Italy) and concluded that co-ops fare better in markets where cooperative principles are already established. In such environments, workers tend to have higher satisfaction, stronger social cohesion, and a clearer sense of shared purpose.Other studies have explored connections between autonomy, well-being, and trust in co-op settings. <a href="https://www.sciencedirect.com/science/article/abs/pii/S0165176514001980">Coad et al</a>, for example, found that increased workplace autonomy significantly affects job satisfaction and life satisfaction. <a href="https://www.emerald.com/insight/content/doi/10.1108/ER-06-2017-0137/full/html">Park et al</a> concluded that worker co-ops in Seoul help moderate the adverse effects of high job demands, indicating that the more democratic the workplace, the stronger the sense of trust and commitment among employees. <h2>Conclusion</h2>With trust in steep decline, it’s clear we need to rethink how our economy and institutions are structured. The scientific literature suggests that worker co-ops aren’t just a feel-good idea, they’re a practical response to a very real problem. I’m not saying they’re a silver bullet, and implementing them at scale isn’t trivial, but if we’re serious about restoring trust then democratizing the workplace deserves to be on the table.<a href="#fnn86fa7twtl9">[6]</a> Given the stakes here, the fact that trust is crucial for a stable society and economy, exploring models that place greater emphasis on cooperation and shared ownership may be one of the most pragmatic steps we can take. <h2><a href="https://bobjacobs.substack.com/p/how-worker-co-ops-can-help-restore">See substack comments here</a> </h2><ol class="footnote-section footnotes" data-footnote-section="" role="doc-endnotes"><li class="footnote-item" data-footnote-item="" data-footnote-index="1" data-footnote-id="xusvv2vycmr" role="doc-endnote" id="fnxusvv2vycmr"><a href="#fnrefxusvv2vycmr">^</a><div class="footnote-content" data-footnote-content="">The World Values Survey is more optimistic, but the data from US GSS is better. Even still, the WVS notes a decline by <a href="https://www.worldvaluessurvey.org/WVSEVStrend.jsp">2%</a>.</div></li><li class="footnote-item" data-footnote-item="" data-footnote-index="2" data-footnote-id="yfk93o9hsxg" role="doc-endnote" id="fnyfk93o9hsxg"><a href="#fnrefyfk93o9hsxg">^</a><div class="footnote-content" data-footnote-content="">The WVS does the same survey in different countries so they can compare data. Since most countries don't have a congress but rather a parliament, the survey question used the term ‘parliament’.</div></li><li class="footnote-item" data-footnote-item="" data-footnote-index="3" data-footnote-id="lssp5cqityt" role="doc-endnote" id="fnlssp5cqityt"><a href="#fnreflssp5cqityt">^</a><div class="footnote-content" data-footnote-content="">In fact, that’s what Marx and the other early socialists were really focused on. They never endorsed a planned/command-economy, which is what much of the West now wrongly equates with socialism.</div></li><li class="footnote-item" data-footnote-item="" data-footnote-index="4" data-footnote-id="mth5zjn2yyk" role="doc-endnote" id="fnmth5zjn2yyk"><a href="#fnrefmth5zjn2yyk">^</a><div class="footnote-content" data-footnote-content="">Given that democracies are higher trust societies, you can probably see where this is going…</div></li><li class="footnote-item" data-footnote-item="" data-footnote-index="5" data-footnote-id="36xlwbpwofc" role="doc-endnote" id="fn36xlwbpwofc"><a href="#fnref36xlwbpwofc">^</a><div class="footnote-content" data-footnote-content="">Inequality has been <a href="https://wid.world/">rising for years</a>. There are <a href="https://media.equality-trust.out.re/uploads/2024/07/The-Spirit-Level-at-15-2024-FINAL.pdf">strong links</a> between all sorts of negative effects and inequality, such as worse conditions for workers, worse gender equality, and worse environmental problems.<a href="https://substackcdn.com/image/fetch/$s_!gdVX!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F5e89c41a-c4ca-4dc1-afe8-5c7c70c42bf4_1454x1130.png"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/f5kmudhiivzhve4nva69" alt="" srcset="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/flpu0e4t275qcwrtknfs 424w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/kwcnpgtlky9rqzpux9iu 848w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/fpaq9cpp4md3zvalwx7c 1272w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/f5kmudhiivzhve4nva69 1456w"></a>Now, it’s difficult to ascertain to what extend one causes the other, but since worker co-ops both decrease inequality, and are better for workers, gender equality, and the environment, it doesn’t really matter. Worker-coops are a way to tackle these issues in any case.</div></li><li class="footnote-item" data-footnote-item="" data-footnote-index="6" data-footnote-id="n86fa7twtl9" role="doc-endnote" id="fnn86fa7twtl9"><a href="#fnrefn86fa7twtl9">^</a><div class="footnote-content" data-footnote-content="">Originally this post also talked about mistrust, but then I realized that I didn’t have a source showing a decrease in trust corresponds with an increase in mistrust. Now most of you will probably say that this is basically tautological, but for the few skeptics among you, I did find a scatter plot:<a href="https://substackcdn.com/image/fetch/$s_!y0hE!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F69525075-bc9d-4aff-a001-0685f7b3ead6_3400x2400.png"><img src="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/hjptmp4njxvhi63ysivd" alt="" srcset="https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/nqgfjffie8vxcomuxsax 424w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/lecn41j5hpj8dvfhyfki 848w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/cp4xh9lsttwbnod9ejgn 1272w, https://res.cloudinary.com/lesswrong-2-0/image/upload/f_auto,q_auto/v1/mirroredImages/mdYv4Zb8MzMALSCQi/hjptmp4njxvhi63ysivd 1456w"></a>To be on the safe side I only talked about a decrease in trust and not about an increased in mistrust, though they’re almost certain both happening in tandem.</div></li></ol> <a href="https://www.lesswrong.com/posts/mdYv4Zb8MzMALSCQi/how-worker-co-ops-can-help-restore-social-trust-1#comments">Discuss</a>]]></description><link>https://www.lesswrong.com/posts/mdYv4Zb8MzMALSCQi/how-worker-co-ops-can-help-restore-social-trust-1</link><guid isPermaLink="false">mdYv4Zb8MzMALSCQi</guid><dc:creator><![CDATA[B Jacobs]]></dc:creator><pubDate>Thu, 03 Jul 2025 19:13:19 GMT</pubDate></item></channel></rss>

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