<p>I don’t think Mollie is advancing the very radical claim that intelligence isn’t heritable. I think she’s saying that in our measurement of intelligence, factors like economic advantage often overwhelm the underlying intelligence variable which we would like to measure. That seems very reasonable and, in fact, true.</p>
<p>There’s a huge conceptual difference between denying that something (in this case, intelligence) EXISTS or is heritable and denying that we can measure small differences in it well enough to base big decisions on small differences in measurements. I’m pretty sure Mollie would make the second claim, not the first. Let’s see what Mollie thinks.</p>
<p>My personal view is that there are probably group-level intelligence differences (just as there are height differences…), but they may well be the reverse of what people naively think they are, and we’ll have to wait a while to know. (In a recent study of infants, for example, Asian babies actually performed slightly worse than white and black babies on simple cognitive tests.) In the meantime, reserving judgment and not putting too much stock in these claims about genetic group-level differences is likely to lead to a more equitable society.</p>