Is America smart enough? IQ and national productivity

National Review, April 15, 1991 by Daniel Seligman

What about the relative weakness of Mongoloid verbal skills? In approaching this question, Lynn notes the familiar male-female ability differences. Like most scholars, he believes that these arose from evolutionary pressures in which men needed visuospatial skills for hunting, and women needed verbal skills for childrearing. The Mongoloids, Lynn believes, took this process a step further. Verbal skills are, of course, centered in the brain's left hemisphere. Lynn hypothesizes that among Mongoloids, the cortex in the left hemisphere was invaded and made to take on more visuospatial processing. There is some evidence to support this view of a different neurological structure for East Asians, although the case is admittedly not closed.

The verbal-visuospatial difference is not the only one that distinguishes Caucasoid and Mongoloid IQ patterns. The two populations also differ in the variability of their scores. A representative sample of Americans or Europeans will show more variability than will an East Asian sample. In the familiar bell-shaped distribution curve, the bell is much narrower for the Japanese--which is what you would expect from such a homogeneous population.

This difference is a major matter, and it is worth focusing hard on the data. Just about all Western populations report a standard deviation of 15 IQ points. (The SD, a basic measure of variability, quantifies the extent to which a series of figures deviates from its mean.) But the SD for the Japanese and other East Asian populations appears to be a shade under 13 IQ points. That difference does not sound like a big deal, and, in fact, it does not change things much in the center of the distribution. But the smaller standard deviation, combined with the higher average IQ, has one important implication for the quality of the Japanese labor force. It means that Japan has relatively few low-IQ workers. In the U.S., about 25 per cent of all workers have IQs below 90 u. only about 15 per cent in Japan). For IQs below 80, the comparable figures would be around 10 per cent for the U.S., around 3 per cent for Japan. There are good reasons to believe that these differences are related to Japan's advantages on the factory floor.

It is curious that economists have been so slow to pick up on the link between IQ and economic performance. Indeed, it is especially curious given economists' increased interest in "human capital." In measuring the value of such capital, the economics profession never seems to get beyond education and training. In a brilliant essay published in 1983 (in a volume called Intelligence and National Achievement), Barbara Lerner chided them for being blind to the much superior measures provided by IQ and other test scores. Dr. Lerner, a psychologist and lawyer, was herself one of the first to write about the connection between IQ and national economies.

Predicting Success

THIS CONNECTION can be approached from several directions, but let us begin with this hard fact: People with high IQs tend to do well in life. There is, or should be, no real controversy about these statements: On average, the rich are more intelligent than the middle class. And the middle class are more intelligent than the poor.