Sailer's opinion of blacks has nothing to do with the discussion. However, that information, along with the claim that Pinker is an "IQ fundamentalist" is enou

Sailer's opinion of blacks has nothing to do with the discussion. However, that information, along with the claim that Pinker is an "IQ fundamentalist" is enough to lead readers unfamiliar with Pinker to suspect that he is racist and dismiss his arguments without further inspection. That is exactly what ad-hominem is about.