I standard-upvoted this at the time, and +1-review-voted more recently. I like it, as a "yes, the work continues" kind of log entry, and it's nice to be reminded that induced meiosis and superSOX were very recent very big deals. ...OK, you got me, two hours later here's a review

A neat progress update, though largely obsoleted by more recent posts (see below).

LessWrong is famously obsessed with the trainable skills and social practice of rationality, and with the prospect of very strong computer intelligence. The biological pathway to improved cognition doesn't get as much discussion, and the timelines to impact are (probably!) somewhat longer, but I remain convinced of its importance. I also strongly agree with the ethical position that

nobody’s civil rights should be in any way violated on account of their genetic code, and that reasonable precautions should be taken to make sure novel human reproductive tech is safe.

and from early 2026, it's nice to be reminded that induced meiosis and super-SOX for naive pluripotency were substantial breakthroughs! My impression is that we're still basically on track to start primate testing in the late 2020s, rather than having basically no idea if or when such things might be possible.

On the other hand, I'm substantially more optimistic than Sarah about the causal predictive power of polygenic scores - at least in principle; don't take me as endorsing any particular predictor or even current practice in general. This is supported by two key stylized facts:

1. sibling genomes are independent-random when conditioned on the shared parent genomes. ^[1] This means that observing a phenotype-genotype correlation among siblings with a shared environment ^[2] really does tell us about causality.
2. most genes have approximately additive effects, and interaction effects are usually small and almost always positive rather than being tradeoffs! See e.g. the heatmap here. An intuition: this is because we're only considering traits which vary between currently-living humans, which are recent enough and weakly-selected-enough that they haven't reached fixation. ^[3] If that didn't help, ask me in person sometime because I have more thoughts this timebox is too narrow to contain.

Finally, what's the state of the art in early 2026?

• many of my friends with young children used polygenic screening aka embryo selection. At time of writing, Herasight is a clear leader, though choice of IVF clinic etc. also matters.
• you can pretty easily do a full-genome sequence for less than $1000; at scale you could likely get the cost down to the 100-500 range, and it keeps falling over time.
• every other method involves doing something new, not just 'getting artificially lucky', and so there are a bunch of as-yet-unsolved challenges like dealing with DNA methylation and making sure all the cell markers are right - not just right-enough-to-mostly-work. This probably adds a couple of years of fiddling after the core tech works, and then extensive trials, to all the timelines below.
• iterated embryo selection would require deriving gametes from embryonic cells, which seems at least as difficult as iterated meiosis with a donor egg - and may take a few months rather than less than an hour per iteration. I think we're 3-5 years away from deriving eggs from stem cells, longer for sperm, and probably 3-5 away from induced meiosis.
• editing, especially multiplex editing, combines really nicely with iterative techniques: you can try some edits, then sequence the cell lines and keep those which worked well without off-targets. For selection-only it's harder, because you have to do the edits before the fertilized egg first divides in order to avoid mosaicism. It's on a promising trajectory for the longer term, at least.
• [another possibility omitted for reasons]

So concretely: if you want to have kids very soon talk to Herasight; if you want to have them later after-you're-30 freeze sperm or eggs (not embryos, for flexibility); if you want to get involved as a researcher or a funder send me an email. The kids are gonna be alright :-)

1. OK, it's actually a lot more complicated than this, but we can do fancier statistics which compensate for things like variation in the fraction of genome inherited from each parent (+/- ~4%), various constraints at particular loci (e.g. homozygous AA/BB parents will have uniformly AB, violating independence), etc. On the upside, we can also do fancier analyses where relatives outside the direct line of descent like cousins also provide (weaker) evidence about genetic effects. ↩︎

2. oh man this one is really tough, even if we account for birth order effects. At some level we're always conditioning on a particular environment; many of the genes we today (accurately) describe as causally contributing to autoimmune disorders were strongly advantageous during the Black Death. Some relevant parts of the environment are changing pretty fast these days though - as an example, measuring "educational attainment" by degree status will tell you something quite different about my grandparents and their grandchildren. But we will correct for what we can, and downweight what we can't; in any case this seems more challenging for cognitive traits than health and medical outcomes. ↩︎

3. incidentally I think it's great that modern civilization has things like "vaccines" and "enough food" and "radically lower infant mortality". 'Selection pressure' is an abstract way to describe people dying, or their children dying, etc., and I believe we can do better. As a bonus, polygenic scores are a far more sensitive and powerful optimization proceedure than variation-and-selection. ↩︎

Bluntly, this cannot possibly work.

Open-weights models will remain useful for general-purpose tasks, including in the common case where earlier context on the situation was not produced by the same model. Breaking the evidence chain is therefore sufficient, and is also easy for the attacker.

Do not confuse desirability for possibility.

I would be very happy to have this essay introduce the best-of collection, as a worked example of (6).

"Yes, obviously!"

...except that this is apparently not obvious, for example to those who recommend taking a "safety role" but not a "capabilities role" rather than an all-things-considered analysis. That's harder and often aversive, but solving a different easier problem doesn't actually help.

I still think pretty regularly on "green-according-to-blue". It's become my concept handle to explain-away the appeal of the common mistake ('naive green'?), and simultaneously warn against dismissing green on the basis of a straw man.

I read Otherness & Control as they were published, and this was something like the core tension to me:

1. Florishing. Elua. First, to thine own self be true. The utility function is not up for grabs. We need not understand CEV; nor may we desist from pursing it. (I can't point to this in more than poetry, but this is The Thing.)
2. Centrally, this is Black, and instrumentally Blue-Black. Yin, sure, but because of green-according-to-blue - a warning against the classic mistakes of the think-only-of-cutting school. (the virtues of white and red seem less neglected, less dismissed, here)
3. But... nor may we desist from pursuing it. A niggling feeling that (maybe) I'm missing something; that "nevertheless, green-qua-green" is a tension worth sitting with, if you can avoid making the usual mistakes.

Musing on attunement has, I think, untangled some subtle confusions. I haven't exactly changed my mind, but I do think I'm a little wiser than I would have been otherwise.

There just aren't that many rivalrous goods in OSS - website hosting etc. tends to be covered by large tech companies as a goodwill/marketing/recruiting/supply-chain expense, c.f. the Python Sofware Foundation. Major conferences usually have some kind of scholarship program for students and either routinely pay speakers or cover costs for those who couldn't attend otherwise; community-organized conferences like PyCon tend to be more generous with those. Honor-system "individual ticket" vs "corporate ticket" prices are pretty common, often with a cheaper student price too.

A key mechanism I think is that lots of people are aware that they have lucrative jobs and/or successful companies because of open source, that being basically the only way to make money off OSS, and therefore are willing to give back either directly or for the brand benefits.

I'd strongly encourage most donors to investigate donating appreciated assets; especially when subject to LTCG tax treatment you can get a very neat double effect: donate the whole value to charity without subtracting CGT, and then claim a deduction for the full value.

We'll suppose each planet has an independent uniform probability of being at each point in its orbit

This happens to be true of Earth, and a very useful assumption, but I think it's pretty neat that some systems have a mean-motion resonance (eg Neptune-Pluto, or the Galilean moons, or almost Jupiter-Saturn) which constrains the relative position away from a uniform distribution.

I would love this list (even) more with hyperlinks.