Are We Getting Smarter? Rising IQ in the Twenty-First Century
by James R. Flynn .
Cambridge University Press, 2012 ($22)

The average person today scores 30 points higher on IQ tests than his or her grandparents did. This observation is the starting point of the new book Are We Getting Smarter? by Flynn, an emeritus professor at the University of Otago in New Zealand.

Best known for documenting the eponymous Flynn effect—the tendency for standardized intelligence testing scores to increase over many decades across the world—Flynn is the right man for the job. Based on analyses of current IQ data, he speculates that we are not born with more mental potential than our ancestors; however, because our modern brain is expected to handle higher-level cognitive tasks from a very young age, our mental capabilities have changed. In particular, we have become more adept at learning theoretical concepts in science and technology.

The gains in IQ are not evenly distributed across populations. Flynn makes predictions about which countries' scores will rise the most and shares recent data showing that women now outshine men.

Yet there is a catch to this IQ trend, one that Flynn calls a “bright tax.” The more intelligent the person, the steeper the decrease in IQ score as a person ages, sometimes by more than 20 points. The cause of this decline, however, remains a puzzle. Flynn reasons that our modern brains require more maintenance to stay sharp, so as we age and use our analytical skills less, our IQ may drop quite steeply.

In fact, interpreting IQ scores can mean life or death. Flynn argues that the U.S. Supreme Court needs to reconsider how it uses IQ scores when determining a person's fate. Convicts who have scores below a certain number cannot be put to death, but with this IQ inflation over time more convicts will face the death penalty unless IQ scores are standardized across different tests and time frames.

Though fascinating, Are We Getting Smarter? often reads like a transcript of a lecture. Flynn tends to explain his ideas with charts and statistics rather than examples. Despite this flaw, the book remains valuable for grasping our changing capacity for learning over time—and our room for growth.