“But what’s inherently wrong with claiming that, say, race a is biologically more intelligent than race b?”
Nothing as long as:
1. You have some kind of evidence for your statement. If you want to claim that the difference is biological, you really need a lot more evidence than if you simply claim they are more intelligent (without making assumptions as to the reason).
How can you know that the difference is biological unless a reliable study was performed demonstrating this fact? And personally, I’m a bit wary of studies – I’m not sure how reliable any of them can be.
2. Even if the members of the race are on average more intelligent than others, you can’t assume that this is true of each member of the race.
Okay, I know the question was asked of Yekke and not of me, so I’ll let him respond now.