German people are great at engineering. Irish people: not so much.

You dont think that’s biological? I absolutely do. Look at the different average IQ scores among european countries. That is biological diversity.

Notions of race and nationality are somewhat arbitrary. 100 years ago the British called the Irish a different race. But these concepts are based on two dimensions of differentness: genetic and cultural

And I guess when you commented on an obsession with racial purity, I thought to myself: he does not understand that race, as defined by genetic difference, is subjective and how you define it is a choice based on “purity” (level of genetic sameness) . It is not at all agreed whether there should be 3 races or 6 or 17 or 50. But it all hinges on the concept of purity aka genetic similarity. Its the central variable in a functional definition of race hence the obsession.