With rare exceptions that relate to autism, IQ is always a fitness proxy. I cannot tolerate the misuse of the IQ/Leftism correlation that have been advanced to explain an obviously confounded aspect of progressive mutational load. This link breaks as IQ increases above the low and high midwit range. This isn't a profound thing either just hate seeing it when it happens.
I will probably write a response article. My immediate comments here though, as I read:
>Mutational pressure has increased over the last sixty years (due to a combination of rising parental age and declining infant mortality).
This is not needed although it would help the theory! Alternatively, selection pressure against leftism could have fallen. I think there's evidence of both these happening.
>Mutational load causes leftist political beliefs.
Yes, more specifically, the average causal effect of an additional de novo mutation on leftism must be above a certain magnitude such that we find a paternal age - leftism causal partial correlation > .06.
>Bronski points out that leftism is correlated with paternal age and mental illness – two potential proxies for mutational load. A major problem with his theory is that there’s another potential proxy for mutational load, namely IQ, which is positively correlated with certain leftist beliefs.
Only paternal age is a proxy for mutational load. Even if mutational load has an effect on IQ and mental illness (I think it does), the correlation between leftism and those things can be basically anything. If the paternal age effects on mental health and leftism are both .1, then you'd expect just a .01 correlation between leftism and mental health under the most neutral assumptions. But this can change to anything under genetic correlation, population stratification, and other things all mixing together. So, for example, I know it would seem leftism and IQ correlate positively -- I think this is due to population stratification mainly -- higher IQ people assortatively mating heavily (literature says the spouse correlation is about .4 for IQ), and selection pressures being weaker among these people, mutation pressures being higher. We know higher IQ men breed later in life, which means they'll give more mutations to their offspring. It's also possible that there's an interaction between leftism and IQ on fertility, changing the selection pressure.
>Since IQ is an obvious potential proxy for mutational load, his theory predicts that such views should be negatively correlated with IQ
So this is not the case, my theory doesn't predict this. The thing I just said it what I think and it seems to be consistent with all of your evidence on IQ and leftism in this article.
>The negative association between IQ and social conservatism casts serious doubt on the claim that mutational load causes leftist political beliefs
I strongly disagree with this conclusion, therefore.
>Cohort or period?
I've been running with a study that says that views mostly don't change within a generation, but when they do they go further right on net. This is consistent with my hypothesizing here and there that the memetic environment has shifted right slightly, thanks to HBD and the internet and so on, softening the genetic decline. https://www.journals.uchicago.edu/doi/abs/10.1086/706889
I am interested in what you are citing and why it would contradict these studies. Because of my experience with HBD and the brain development fields, I'm starting off feeling a little incredulous toward contradictory studies.
That said, period effects can be explained by Social Epistasis Amplification. I have a mathematical model of this in my forthcoming book -- the parameters aren't estimated, but as long as the gene pool is going left, the shift can be amplified by the leftization of ideas springing from increasingly genetically leftist idea creators.
>David Ekstam examines change in attitudes to homosexuality and concludes that “both period and cohort effects have contributed to the increase in
The study is inconclusive, at least 1 of the three models is consistent with no period effect and only a cohort effect.
...
Okay without going over every study here, they seem good enough that it's not just researcher bias causing the results. There should be a meta analysis on this, looking at more than attitudes on homosexuality as well as pooling together the cohort and period effects, because I'm seeing a lot of deviation from study to study. It's looking like 30-50% cohort effect, the rest period.
This is actually decent evidence for genetic causation. With homosexuality particularly, we know gays themselves are becoming more common because paternal age as well as selection pressure are favoring bisexuals and homosexuals. The data is generally consistent with genetic change followed by a social amplification due to politics and so on -- individual's opposition to gays weakens as they accumulate in the gene pool because it's more costly and the ideas will all be gayer on average. Whereas a pure idea model makes barely any logical sense, and an environmental toxin model would predict pure period effects unless you add an epicycle about fetal/childhood chemical sensitivity.
>The evidence reviewed above is not inconsistent with a weak version of Bronski’s thesis whereby the rise of leftism is partly explained by genetic changes
I would say instead "the evidence reviewed above is not inconsistent with a modified version of Bronski’s thesis whereby the rise of leftism is explained by genetic changes followed by social epistasis amplification".
>It is far from clear that mutational load causes leftist political beliefs.
My priors on finding a paternal age effect under a good family level design haven't changed much except that it's slightly more likely we find an effect size that explains 30-60% of the shift left instead of 100%, the rest being due to social epistasis amplification.
>Period effects cannot be due to genetic changes because they involve multiple cohorts simultaneously shifting their beliefs.
Under SEAM, the ultimate cause is genetic change. So, in a sense, it's theoretically possible for period effects to be caused by temporally preceding cohort effects which are genetic in origin.
>Mutational pressure may have made a small contribution to the rise of “leftism” (i.e., the decline of social conservatism) over the last sixty years. But it seems very unlikely to be a major contributor.
I think a simple and comprehensive definition of culture would be "all of the man-made environment". That is how I think of it at least.
With rare exceptions that relate to autism, IQ is always a fitness proxy. I cannot tolerate the misuse of the IQ/Leftism correlation that have been advanced to explain an obviously confounded aspect of progressive mutational load. This link breaks as IQ increases above the low and high midwit range. This isn't a profound thing either just hate seeing it when it happens.
https://open.substack.com/pub/aporiamagazine/p/can-mutation-load-explain-the-rise?r=1bt0wh&utm_medium=ios
Are you going to respond to this
I will probably write a response article. My immediate comments here though, as I read:
>Mutational pressure has increased over the last sixty years (due to a combination of rising parental age and declining infant mortality).
This is not needed although it would help the theory! Alternatively, selection pressure against leftism could have fallen. I think there's evidence of both these happening.
>Mutational load causes leftist political beliefs.
Yes, more specifically, the average causal effect of an additional de novo mutation on leftism must be above a certain magnitude such that we find a paternal age - leftism causal partial correlation > .06.
>Bronski points out that leftism is correlated with paternal age and mental illness – two potential proxies for mutational load. A major problem with his theory is that there’s another potential proxy for mutational load, namely IQ, which is positively correlated with certain leftist beliefs.
Only paternal age is a proxy for mutational load. Even if mutational load has an effect on IQ and mental illness (I think it does), the correlation between leftism and those things can be basically anything. If the paternal age effects on mental health and leftism are both .1, then you'd expect just a .01 correlation between leftism and mental health under the most neutral assumptions. But this can change to anything under genetic correlation, population stratification, and other things all mixing together. So, for example, I know it would seem leftism and IQ correlate positively -- I think this is due to population stratification mainly -- higher IQ people assortatively mating heavily (literature says the spouse correlation is about .4 for IQ), and selection pressures being weaker among these people, mutation pressures being higher. We know higher IQ men breed later in life, which means they'll give more mutations to their offspring. It's also possible that there's an interaction between leftism and IQ on fertility, changing the selection pressure.
>Since IQ is an obvious potential proxy for mutational load, his theory predicts that such views should be negatively correlated with IQ
So this is not the case, my theory doesn't predict this. The thing I just said it what I think and it seems to be consistent with all of your evidence on IQ and leftism in this article.
>The negative association between IQ and social conservatism casts serious doubt on the claim that mutational load causes leftist political beliefs
I strongly disagree with this conclusion, therefore.
>Cohort or period?
I've been running with a study that says that views mostly don't change within a generation, but when they do they go further right on net. This is consistent with my hypothesizing here and there that the memetic environment has shifted right slightly, thanks to HBD and the internet and so on, softening the genetic decline. https://www.journals.uchicago.edu/doi/abs/10.1086/706889
Also, openness correlates with leftism moderately. But openness falls a little when people age, yet newer generations start with much more openness. So again, all of the leftism accumulation seems to be between generations. https://journals.sagepub.com/cms/10.1177/09567976211037971/asset/images/large/10.1177_09567976211037971-fig3.jpeg
I am interested in what you are citing and why it would contradict these studies. Because of my experience with HBD and the brain development fields, I'm starting off feeling a little incredulous toward contradictory studies.
That said, period effects can be explained by Social Epistasis Amplification. I have a mathematical model of this in my forthcoming book -- the parameters aren't estimated, but as long as the gene pool is going left, the shift can be amplified by the leftization of ideas springing from increasingly genetically leftist idea creators.
>David Ekstam examines change in attitudes to homosexuality and concludes that “both period and cohort effects have contributed to the increase in
The study is inconclusive, at least 1 of the three models is consistent with no period effect and only a cohort effect.
...
Okay without going over every study here, they seem good enough that it's not just researcher bias causing the results. There should be a meta analysis on this, looking at more than attitudes on homosexuality as well as pooling together the cohort and period effects, because I'm seeing a lot of deviation from study to study. It's looking like 30-50% cohort effect, the rest period.
This is actually decent evidence for genetic causation. With homosexuality particularly, we know gays themselves are becoming more common because paternal age as well as selection pressure are favoring bisexuals and homosexuals. The data is generally consistent with genetic change followed by a social amplification due to politics and so on -- individual's opposition to gays weakens as they accumulate in the gene pool because it's more costly and the ideas will all be gayer on average. Whereas a pure idea model makes barely any logical sense, and an environmental toxin model would predict pure period effects unless you add an epicycle about fetal/childhood chemical sensitivity.
>The evidence reviewed above is not inconsistent with a weak version of Bronski’s thesis whereby the rise of leftism is partly explained by genetic changes
I would say instead "the evidence reviewed above is not inconsistent with a modified version of Bronski’s thesis whereby the rise of leftism is explained by genetic changes followed by social epistasis amplification".
>It is far from clear that mutational load causes leftist political beliefs.
My priors on finding a paternal age effect under a good family level design haven't changed much except that it's slightly more likely we find an effect size that explains 30-60% of the shift left instead of 100%, the rest being due to social epistasis amplification.
>Period effects cannot be due to genetic changes because they involve multiple cohorts simultaneously shifting their beliefs.
Under SEAM, the ultimate cause is genetic change. So, in a sense, it's theoretically possible for period effects to be caused by temporally preceding cohort effects which are genetic in origin.
>Mutational pressure may have made a small contribution to the rise of “leftism” (i.e., the decline of social conservatism) over the last sixty years. But it seems very unlikely to be a major contributor.
Still no better theory!