I think he was alluding to that book when he posted those bell curves. Another conclusion of the book is that unfortunately, the blacks on the low end of the IQ spectrum reproduce at far greater frequency than the Clarence Thomases, Thomas Sowells, Ben Carsons, et al. Instead, low IQ mates with low IQ and gives birth to low (or lower) IQ.
Welfare is what enables that.
How many kids would an woman have, if she had to support them herself from a minimum wage job?