What Can We Learn from “Not Much More than g”?

A series of papers showing that measures of general cognitive ability predicted performance on the job and in training and that measures of specific cognitive abilities rarely made an incremental contribution to prediction led to a premature decline in research on the roles of specific abilities in the workplace. Lessons learned from this research include the importance of choosing the right general cognitive measures and variables, the relative roles of prediction vs. understanding and the need for a wide range of criteria when evaluating the contribution of specific skills such as complex problem solving. In particular, research published since the “not much more than g” era suggests that distinguishing between fluid and crystallized intelligence is important for understanding the development and the contribution of complex problem solving.