This paper examines the argument presented in The Bell Curve. A centra
l argument is that one factor-g-accounts for correlation across test s
cores and performance in society. Another central argument is that g c
annot be manipulated. These arguments are combined to claim that socia
l policies designed to improve social performance cannot be effective.
A reanalysis of the evidence contradicts this story. The factors that
explain wages receive different weights than the factors that explain
test scores. More than g is required to explain either. Other factors
besides g contribute to social performance, and they can be manipulat
ed.