Discussion about this post

User's avatar
Kryptogal (Kate, if you like)'s avatar

Hm. I mean, I'm also already sold on the education doesn't do anything and nature is 80% bit too. But I find your life philosophy truly strange. Also, I've been an egg donor, and the sophisticated clinics absolutely know all this, because when you submit all your information and go through all the genetic tests, the potential recipients who are searching for a donor don't just want to know about you, they want to know about your parents, grandparents, siblings, and sometimes even cousins. So yeah, they're shopping on a family, not just a person, genericslly.

But in their case it makes sense, since they are literally shopping for gametes in a catalog from total strangers that they won't have to live with or ever even meet, so might as well select whatever they think is "the best". But I can't understand literally changing your own life strategy and making yourself less happy for some entirely hypothetical future people long after you're dead and an assumption they you'll help their status be a few percentage points higher than it would be otherwise. All genes get remixed so many times over the generations that there's basically no difference between your own descendants and those of any of your relatives once you get past a couple generations, and why do you care about an unknown person you'll never know and hypothetical future, more than your own very concrete current wellbeing anyway?? You don't have to answer or justify your values, I just think it's odd.

Came here more to point out that the fact that virtually all societies had bastard laws up until about the 20th century seems to throw a big wrench in this. Most of history elite men were absolutely free to knock up as many women as they could get away with, and those children were not permitted to take their family name and had zero legal rights to recognition of paternity. So of course those elite men reserved only the highest status woman they could bag to be the one who would have children who carried on their name. But their dispersing their genes through lower status families doesn't seem to have done much to drag them up, and we'd have no way of knowing anyway. The other thing is that you focus here on elite men using exactly this method ,and yet they always have and just reserved the assortative mating to their legally recognized marriage and children. Plus intelligence is more heritable from the maternal line than the paternal, especially for boys who cannot get any of the cognition genes located on the X from their dad. So the maternal line being smart is likely more important than the other way around, though I suppose that might even explain why having a bunch of low class bastards doesn't change much, since really it's the high class maternal line that's more of the persistent lineage (especially for males).

Expand full comment
Sol Hando's avatar

Came here from the genetic engineering post. Long comment incoming, but skip to the end for the TLDR if it gets boring.

My understanding of heritability, and what causes regression to the mean seems to be different than yours, and leads to different conclusions about the importance of family background, vs. the importance of individual genetics. Although I'm a layman so it could very well be my incorrect understanding (and I ideologically lean towards individual over group identity/relevance so that could make me biased).

Here's my understanding;

Regression to the mean, especially for traits influenced by a large number of genes, occurs regardless of ancestry. Even with two high-IQ parents, their child’s genetic makeup is likely to regress toward the population average.

Hypothetically, if there were 100 important IQ-related genes, with the average person having 50 positive genes, the top 1% of children (assuming random 50/50 inheritance) would have about 62 positive genes. If two individuals from this top 1% were paired, their child would have a 50% chance of inheriting each gene from each parent. The child’s expected number of positive genes would remain 62 if the parents had identical positive genes.

However, if the overlap between the parents’ 62 positive genes is only 50% (31 shared genes, 31 unique genes), the child is guaranteed only to inherit those 31 shared genes. For the remaining 31 unique genes from each parent, the child inherits each with a 50% probability. This increases the variance in the child’s gene count around the expected value of 62.

In reality, since there are way more than 100 IQ producing genes (and possibly the result of Epistasis, multiple genes which together create an effect, but alone are neutral. This would have worse than 50/50 inheritance odds), the regression to the mean would be stronger than assuming just a 50/50 inheritance. If parent A had a combination of 2 genes that together produced higher IQ, and parent B didn't overlap with those two genes (with their high IQ deriving from somewhere else), the child would have to win the genetic lottery twice in order to benefit. Making the actual heritability of that single-parent IQ gene pair at 25%. Since the pool of IQ-enhancing genes (and gene combinations) is small compared to the vast number of neutral or non-IQ-affecting genes and gene combinations there’s more room for downward variation than upward. This asymmetry makes larger losses in positive IQ genes more likely than small gains.

Now when it comes to how I understand this would apply to lineage;

On the same hypothetical shown above, when two parents have 62 random IQ producing genes or gene combinations that are independent of each other, the expected mean of offspring would depend on how much overlap there is. If parent A has an IQ gene pair that parent B does not have, the child will have to get lucky for each gene, so 1/2 times the number of different genes that contribute to that one IQ effect. If it was 2 genes, each with 50% heritability, then the chance of a child inheriting those IQ genes would be only 25%, while it would be 100% if the parents shared the same mutation.

Larger losses would be more likely than lesser gains, as the space of IQ increasing genes decreases the higher IQ you are, and the space of normal IQ genes increases, causing regression to the mean. However, if you assume that the 62 positive genes are not randomly selected, but are somewhat dependent on each other, or on some 3rd factor (like for example, shared ancestry with lots of intermarriage), then the overlaps (and hence guaranteed inheritance) of those 62 genes and gene pairs would be expected to be a lot higher! Therefore, there would be a higher chance of heritability of IQ (and other heritable factors) when you concentrate the blood a bit.

Of course the heritability of clusters of genes is not completely random, but where IQ is derived from combinations of genes that aren't clustered, there would be a meaningful advantage to having more overlap among IQ producing genes. Shared lineage would increase the likelihood of that overlap.

Essentially, (at least as I understand it) the lineage shouldn't matter for the likely IQ of your children with someone, unless there is significant shared lineage or shared concentration of IQ genes. Person A with high IQ Japanese familial lineage marrying Person B with high IQ New England WASP lineage will have the same mean expected mean IQ, and same downward variance, as either of them marrying an equivalent high-IQ prole. Unfortunately, this would mean there's literally no way to benefit from the advantages of lineage-IQ, unless you're already part of such a lineage, or otherwise have access to a closely genetically related person who's also benefited from at least a couple of generations of traditional non-lineage assortive mating.

Darwin married his cousin after all, and I’d imagine the high-IQ families Clark describes originated from a small, genetically distinct group—whether an invader stock or a semi-legendary aristocracy. These families likely intermarried mostly exclusively, concentrating their advantageous “blue blood,” so to speak. This would explain the persistence of high IQ among elite families without suggesting that someone should specifically target high-IQ lineage unless that lineage is closely related to their own.

This concentration of lineage may also increase the risk of genetic diseases and single genes that cause significant IQ deficits. While such outcomes were likely managed by ensuring those with severe issues did not reproduce—either through exclusion, disinheritance, or marriage outside the lineage—the negative effects of inbreeding were still present. Over time, these risks may have been outweighed by the positive effects of preserving and reinforcing high-IQ genes within the lineage.

Cultural practices may have helped mitigate some of the downsides of inbreeding. For example, in aristocratic families, it was common to send non-heirs into the clergy, where celibacy may have acted as a release valve for those with undesirable traits or unlucky genetic inheritance. This practice may have reduced the reproductive impact of deleterious genes.

Anecdotally, examples like that Kennedy sister (her name I don't remember)—who was lobotomized and institutionalized due to developmental issues—many indicate elite families may have overrepresented genetic diseases. I've read this was quite common among the elite, but I have no real data.

TLDR: My understanding is that familial IQ only matters if you’re already part of a high-IQ lineage or have close IQ relatives you can marry. Otherwise, building a long-term high-IQ lineage requires either genetic testing (to find someone who shares the most positive genes with you, though this is practically impossible without a centralized database) or setting up your descendants to intermarry within the family. This might only work if you come from a unique, relatively unmixed genetic stock (e.g., Iceland, the Sámi, Japan). For most people, especially those from settler states like America, targeting familial IQ wouldn't be feasible.

If I were trying to create a long-term genetic winner lineage (a goal I personally resonate with but am not focusing on right now), I’d prioritize finding a high-IQ, accomplished woman who shares that goal. The current best approach would likely involve IVF, embryo selection, and possibly surrogacy, though there are trade-offs (I've read suboptimal gestation conditions from surrogacy can offset genetic advantages). Passing down these values and philosophies to your children is probably the key so they continue the trend over multiple generations. Gwern’s excellent piece on this topic is worth reading for what the possible future developments would look like, but I am sure you've already seen it: https://gwern.net/embryo-selection

Alternatively, you could bypass the need for a partner who shares your goals. You could find a high-IQ egg donor and raising 5+ children with surrogates. You wouldn’t need your partner to be ideal—just supportive or ambivalent (allowing you also to select for other non-trivial traits, like attraction and emotional compatibility). Finding high-IQ egg donors isn’t impossible, as shown by the Hwang affair, where researchers donated eggs for his cloning experiments despite the dubious nature of his work: https://www.youtube.com/watch?v=ett_8wLJ87U

Success is largely heritable, but a targeted environment can amplify those advantages. The Polgar Sisters, raised by a father who believed genius could be nurtured through environment: https://slatestarcodex.com/2017/07/31/book-review-raise-a-genius/ Coincidentally the English translation was sponsored by SSC readers: https://slatestarcodex.com/Stuff/genius.pdf

I’d appreciate your thoughts here, as I agree with your goals but understand heritability differently (and an incorrect understand would have very material effects on my own approach to my descendants). As for why, I believe that intelligence, creativity, and ability thresholds for productivity are rising rapidly. 1,000 years ago, almost anyone could farm; 100 years ago, industrialization favored the systems-makers; 20 years ago, controlling information became key with the internet; each of these setting the minimum necessary intelligence to produce something valuable much higher, and in 10 years, AI may eliminate 95% of low-performing white-collar jobs. If descendants don’t rank among the top 1% performers of the top 1% most difficult jobs, they will probably end up at the mercy of AI, the oligarchs controlling it or government-controlled UBI.

Edit: Made changes for clarity of my thoughts. After writing that out it may warrant writing a more formatted and edited post instead of just a comment.

Expand full comment
17 more comments...

No posts