Does IQ measure ability for complex cognition?

Abstract

A popular conception of the “intelligence,” or g, thought to be measured by IQ tests, is that of a cognitive “strength” variable that facilitates complex cognition such as reasoning and problem solving. Yet test items seem remarkably un-complex when compared with everyday cognition. Here, typical verbal and non-verbal test items are examined and arguments asserting their complexity are challenged. In contrast, several lines of research indicate how “real life” cognition is much more complex than that required by such items. The claim that an IQ-job performance correlation is stronger for more complex jobs is also challenged. This leads to the suggestion that other sources of variance, including cultural, affective, and other non-cognitive factors, may explain differences in test performance. An alternative explanation for the still-puzzling “Flynn effect” is proposed, with the idea that IQ differences reflect cultural “distance” (from possibly equal, but different, complexities) rather than a universal cognitive “strength.”