A Reason for Reason

Article excerpt

THE SOURCE: "Why Do Humans Reason? Arguments for an Argumentative Theory" by Hugo Mercier and Dan Sperber, in Behavioral and Brain Sciences, April 2011.

FOR ALL ITS STELLAR ACHIEVEMENTS, human reason seems particularly ill suited to, well, reasoning. Study after study demonstrates reason's deficiencies, such as the oft-noted confirmation bias (the tendency to recall, select, or interpret evidence in a way that supports one's preexisting beliefs) and people's poor performance on straightforward logic puzzles. Why is reason so defective?

To the contrary, reason isn't defective in the least, argue cognitive scientists Hugo Mercier of the University of Pennsylvania and Dan Sperber of the Jean Nicod Institute in Pads. The problem is that we've misunderstood why reason exists and measured its strengths and weaknesses against the wrong standards.

Mercier and Sperber argue that reason did not evolve to allow individuals to think through problems and make brilliant decisions on their own. Rather, it serves a fundamentally social purpose: It promotes argument. Research shows that people solve problems more effectively when they debate them in groups--and the interchange also allows people to hone essential social skills. …