The P-FIT model is a major step forward in understanding biological causes of intelligence. It is consistent with evidence on the influence of working memory and speediness upon intelligence, and with models that emphasize the role of interaction between modules to produce intelligence. The contribution to understanding genetic contributions is problematical, due to the difficulty of isolating the genes involved.

Stanovich & West claim that the positive correlation between reasoning tasks negates the view that errors in reasoning are due to failures in information processing. This is not correct. They conjecture that errors in reasoning are associated with conflicts between intentional and associative reasoning. This interesting proposition suggests studies relating situational characteristics to the quality of human reasoning.