Reading across what Wade apparently argues in his book and what HBD people write in general (here, for example), it all seems to boil down to the same old racism: races are defined, they are assigned some good or bad characteristics, and then discrimination can be justified and poverty "explained" with those supposed differences. Only the terminology has changed.
In a more detailed fashion, one could summarise their current argumenation as follows:
- Human populations differ demonstrably in heritable characteristics such as skin colour.
- There is no reason to assume that human populations do not likewise differ in heritable cognitive or behavioural characteristics such as intelligence, honesty, aggressiveness, lazyness etc. Given that evolution is true, the burden of evidence is in fact on the side of those who argue that such heritable cognitive or behavioural differences do not exist to any significant degree.
- The presumed cognitive and behavioural differences explain the differential achievement of human populations in the areas of culture, science, industry, commerce, etc.
- Therefore, attempts to help the disadvantaged with foreign aid or affirmative action programs are doomed. What is more, Europeans and Americans do not need to feel bad about the history of racism, colonialism and imperialism and its lasting consequences. Those who are poor are poor because they are inferior, and the wealthy and powerful have no responsibility for the situation.
Wade apparently adds the claim that the best scientific explanation for the presumed differences in cognitive and behavioural traits between human populations is adaptation. For example, the past few hundred years are assumed to have seen rapid evolution of Europeans so that they are now better adapted to living in complex industrial societies than other "races". However, this claim is at the same time ludicrous, self-defeating and irrelevant. First, it is just seems unlikely that such massive selection could happen over such a short time period given our long generation times and low number of children, and at the same time as all the other, much more crucial traits we are being selected for at the same time, e.g. disease resistance (black plague, anybody?).
Second, at least to me the idea that humans can evolve so quickly seems to make nonsense of the idea of races having any predictive value for the supposed traits of interest. I mean, if that is the case then even under the logic of the HBD people the supposedly less well adapted "races" should become well adapted within the next two centuries, and thus the segregation some of them argue for is superfluous.
Third, those of us who know our evolutionary theory and population genetics know that many differences between populations are the result of drift instead of selection. However, for the purposes of making the HBD/racist argument Wade's adaptationism is irrelevant, they only need to claim that there are significant differences. So let's ignore this specific claim and look at the others.
The first claim, that human populations differ genetically, is quite obviously true. To skin colours we could add much more relevant characteristics such as cold tolerance (Inuit), efficiency of oxygen uptake (Aymara), lactose tolerance (many Europeans) or disease resistance (peoples with a long history of urbanisation in general). That being said, these differences are never absolute. While we could arbitrarily define populations or "races" and find that they have different mean values for some quantifiable character, they will often show wide overlap if all variation is taken into account, and every individual trait may be distributed in a completely independent fashion.
And that is, of course, already where the whole argumentation falls apart. There is simply no objective, scientific way of circumscribing human races, and thus racism does not make a lot of sense. But let us press on for the moment.
The second claim, that there are significant heritable cognitive and behavioural differences between "races", suffers from the same problems as the first, only more so. Even if cognitive abilities and behaviour are heritable - and it is quite obvious that there is a strong cultural influence - there is massive overlap in all of them between whatever "races" one would like to define. But we would rarely ever get that far because most of these traits cannot even be quantitated or measured reliably. Results of IQ tests, for example, are well known to be somewhat problematic. To some degree, the tests can be trained for; even worse, how do you test the IQ of a person who was not raised to understand the kind of question used in such a test, or who has never learned to read and write? And comparatively speaking, intelligence is an easy one, much less complicated to capture than some supposed adaptation to living in complex industrial societies!
At this point already, I only have the option of concluding that the HBD project has no legs to stand on. However, the third claim leads to a more interesting, more complicated question: What does determine the fate of human societies? Although I am much less an expert for that than for biology, evolution and genetics, I would like to spend another post examining it in more detail. Enough for the moment.