The GrandMaster... Intelligence

The GARANDMASTER- John Defensor, Raul Teehankee, Amiel Aguilar Cabanlig and CHESS grandmaster Eugene Torre

By Rony V. Diaz

THE conventional wisdom about intelligence is that it’s inherited. Children of bright parents are generally brighter than the progeny of the less bright. This was the theory that was propounded in 1994 by Richard J. Herrenstein and Charles Murray in their book The Bell Curve. It has been roundly denounced as racism masquerading as science although the authors drew their conclusions from a large body of research in both psychology and the cognitive sciences that they evaluated with great care and circumspection. The opponents of the hereditarian theory of intelligence found it easier to question the authors’ motives rather than their methodology. Studies on intelligence are fraught. Establishing heritability is slippery. Furthermore, however “detached” a researcher would like to be, subtle biases and ambiguities are bound to color his or her judgments. IQ tests measure intellectual inequalities that are, many believe, natural and not cultural. There are even those who go as far as to theorize that intelligence is encoded in the genes. This is the basis of the belief that Azhkenazi Jews are the brainiest ethnic group followed by East Asians, whites in generals, with the blacks bringing up the rear. It’s therefore a great service to all of us that Robert E. Nisbett, a cognitive psychologist at the University of Michigan at Dearborn, published last month Intelligence and How to Get It. Why Schools and Culture Count (W.W. Norton). He began with a careful critique of hereditarism, which he countered with nonhereditary factors in determining intelligence. Nisbett accepts IQ tests as instruments that measure something “real.” They measure “fluid” intelligence (abstract reasoning skills) and “crystallized” intelligence or knowledge. Within the same family there are inequalities in fluid intelligence. Nisbett, however, rejects the hereditarian claim that 75 percent to 85 percent of intelligence is inherited. He thinks that it’s less than 50 percent. The higher estimates were made by comparing blood relatives—identical twins, fraternal twins, siblings—who grew up with different adoptive families. But adoptive families are not all the same. The more affluent tend to give their adopted children more “cognitive stimulation” than the poorer ones. The data then yield erroneously high estimates of IQ heritability. The right conclusion is that there’s no fixed value for heritability. The average difference in IQ is entirely environmental. Using this logic, Nisbett explained the disparity in average IQ between white and black Americans. The IQ gap is purely environmental. In fact, this gap is closing. Over the last 30 years, the measured difference in IQ between white and black children has decreased from 15 points to 9.5 points. From studies in population genetics, Nisbett found that African-Americans as a consequence of slavery, have on average about 20 percent European genes. But the proportion of European genes ranges widely among individuals—from near zero to more than 80 percent. The conclusion is inescapable: if the gap is genetic, then blacks with more European genes ought to have, on average, higher IQs. The fact is they don’t. As regards the higher intelligence of Ashkenazi Jews and East Asians, Nisbett found that if the IQ tests were properly designed and normed, Americans would score slightly higher than East Asians. If differences in IQ are largely environmental, then what can be done to eliminate intellectual disparities? The most dramatic results came from adoption. When poor children are adopted by wealthier parents, their IQ increases by 12 to 15 points. Early childhood education increases the intelligence of children measurably. Nisbett is for scaling up pre-school programs because even in adolescence, those children are 10 points ahead in IQ than those who did not attend a pre-school program. For older kids, Nisbett recommends telling high school students that intelligence is expandable and they are in control of their own IQ. Students, once convinced, tend to work harder and earn higher grades. This is particularly true of girls who have been made to believe that they are genetically disadvantaged in science and math. Once this mindset is overcome, they excel because they are deprived of an excuse for failure. I suggest that parents, teachers and school administrators give up the idea that children are differently endowed intellectually. Cognitively, we are all equal. And good education can do a lot to expand the brainpower of a nation.