James Watson, for those who don't know, helped to unravel the structure of DNA and ended up winning the Nobel Prize in 1962. He hasn't been doing great lately though. He's currently caught up in a controversy over saying stuff like this:

Dr Watson told The Sunday Times that he was "inherently gloomy about the prospect of Africa" because "all our social policies are based on the fact that their intelligence is the same as ours – whereas all the testing says not really". He said there was a natural desire that all human beings should be equal but "people who have to deal with black employees find this not true".

Now, I'm not a poster boy for political correctness. If scientific truth happens to uncover unpleasant or uncomfortable truths, you need to speak out, regardless of how you might be portrayed.

But that isn't what happened here. Watson is just making specious claims about poorly-understood phenomena. Reasonable people have a hard time finding any kind of consensus on a working definition of intelligence, and testing is a pretty blunt instrument. Even if the testing bore out differences, we're not sure whether we're measuring heritable traits.

Watson also says:

"There is no firm reason to anticipate that the intellectual capacities of peoples geographically separated in their evolution should prove to have evolved identically. Our wanting to reserve equal powers of reason as some universal heritage of humanity will not be enough to make it so."

This is true enough, but we don't have nearly enough evidence or a decent theoretical framework to talk intelligently about whether those differences actually exists, and if they do in what ways they differ.

I currently like the working definition of intelligence as the ability to acquire invariant representations of spatio-temporal patterns, and use those patterns to make good inferences about the past and present and good predictions.

This has different dimensions, depending on modality (vision, audition, motor control, etc.). Tests like the Wechsler seem to do a decent job of breaking down intelligence into various testable components, but not everybody, obviously, buys into it as the be-all-end-all of intelligence testing. And I'm not even familiar with large scale comparisons between races.

Anyway, for the moment it appears that Watson is talking out of his ass. Oh, and that he's a racist old codger.