[tptacek]

Right, just so we're clear that heritability isn't genetic determinism; it's a correlation statistic. All sorts of things are heritable that are absolutely not fixed by genetics. And there are things fixed by genes that aren't meaningfully heritable!

[Dylan16807]

Of course it's not determinism but it is statistically causal. The point is the distribution of the student body is going to be different in a pretty significant way.

[tptacek]

"Statistically causal"?

[Dylan16807]

You said correlation, I said "causal" because it's going from parent to child.

"statistically" meaning any individual child could have any IQ, and genes are only one factor out of many, but when you measure the entire group the graph of IQs is going to look different.

A comparison would be like, filtering IVF in 50 couples based on X/Y chromosomes and measuring height. That filter doesn't decide how tall a child will be, but it does shift the average. The filter would cause a height change, on a statistical basis.

[tptacek]

This is all very fuzzy. "Heritability", of the sort that we have numbers from peer-reviewed articles on, means something specific, and that specific meaning is not genetically causal.

[Dylan16807]

That wiki page lists a lot of evidence that a meaningful chunk is genetically causal. Is there a strong reason for me to think otherwise? Even the pessimistic numbers from gene mapping that are cited are .1-.2

[tptacek]

I mean, start with the fact that it's a correlation statistic and not a causal statistic and just work your way back from that. Heritability --- of the kind with a research literature cite record --- is simply the ratio of phenotypical variation to genetic variation. The number of fingers on your hand is not, in that statistic, highly heritable.

I don't think there's a Wikipedia cite that's going to get you over that speed bump in your argument.