The penultimate talk of the first day comes from William Dickens of Northeastern University. He's talking on "Cognitive Ability: Past and Future Enhancements and Implications." (Abstract and bio.)
Dickens is extolling the virtues of the embattled IQ test. He says it has more predictive power over a person's success than any other measure (such as parents' income). (Somewhere, Charles Murray's ears are burning.) Dickens is discussing the controversy over general versus specialized intelligence, and showing how current data seems to indicate that cognitive ability is not very malleable. People, particularly children, can see rapid gains in their abilities if, for example, they move from foster care to adoption, or if they are put in intensive schooling. But the gains eventually disappear once people reach adulthood.
But, he says, there have been many documented cases of countries where the general intelligence level has increased greatly, and stayed that way. Americans have apparently gotten markedly smarter over the last six decades. (Don't tell Bill Maher.) The gains are uneven: much greater gains in areas of fluid reasoning, with little progress on learned skills like math.
Dickens goes through controversies over these findings — disputes about whether the gains are real, and questions about how they could happen if, as many think, intelligence is mostly general and mostly a matter of genetics. Dickens has found, however, that environment can explain most of the improvement. This makes intuitive sense, he says, as all sorts of aspects of the way we try to improve our skills would not be possible if we couldn't train and better ourselves. In other words, he says, there is a good reason to believe that practice and training makes us better. (Will he work back to the earlier point about how gained intelligence eventually fades?)
He's bringing it together now: Society has gotten smarter. Why? He says it's not just habits of mind. It's the fact that training in particular areas actually increases our gray matter, which increases our overall intelligence. As the world becomes faster-paced and more virtual, he says, we think more and more, and our abilities increase even more. (Not too different from Steven Johnson's argument.) Cognitive enhancement, Dickens says, is already here.
Intriguing, but, um, can't our skull only hold so much gray matter and aren't we pretty close to it already?