Enlightenment Now: The Case for Reason, Science, Humanism, and Progress

by Steven Pinker

But all this changed in a version of the experiment in which the treatment was switched from boring skin cream to incendiary gun control (a law banning citizens from carrying concealed handguns in public), and the outcome was switched from rashes to crime rates. Now the highly numerate respondents diverged from each other according to their politics. When the data suggested that the gun-control measure lowered crime, all the liberal numerates spotted it, and most of the conservative numerates missed it—they did a bit better than the conservative innumerates, but were still wrong more often than they were right. When the data showed that gun control increased crime, this time most of the conservative numerates spotted it, but the liberal numerates missed it; in fact, they did no better than the liberal innumerates. So we can’t blame human irrationality on our lizard brains: it was the sophisticated respondents who were most blinded by their politics. As two other magazines summarized the results: “Science Confirms: Politics Wrecks Your Ability to Do Math” and “How Politics Makes Us Stupid.”