Chapter 3, The Economic Pressure to Partition, Chapter 4, Steeper Ladders, Narrower Gates Summary and Analysis

Many hold that people with different IQ end up with different jobs because of education - those with the best scores go to the best schools, and so on. SATs don't matter once one has gained entrance into the right school. The authors argue that education is only part of the explanation, for intelligence is needed to learn the material it is also needed for 'hollow credentialing'. Educational degrees are job-tickets for those who could have done the job without the degree.

But IQ is still important, as IQ makes - on average - for better employees. Lawyers with higher IQs are more productive on average, as are carpenters. The tie between cognitive power and job performances is quite high. Test...