THE RATIONAL ANIMAL

How do people make decisions, and how has the brain evolved to make the choices that it does?

Kenrick (Psychology/Arizona State Univ.; Sex, Murder, and the Meaning of Life: A Psychologist Investigates How Evolution, Cognition, and Complexity are Revolutionizing our View of Human Nature, 2011) and Griskevicius (Marketing and Psychology/Univ. of Minnesota) argue that our choices reflect a deep evolutionary wisdom. “Although it feels as if there is just one single self inside your head,” they write, “your mind actually contains several different sub-selves, each with a specific evolutionary goal and a completely different set of priorities.” For the most part, the authors avoid scientific jargon and touch on game theory only when it enters into their popular bailiwick. They vigorously investigate the subselves that readers may be wary of from the outset, since it is so much more comfortable to think of ourselves as a single creature. They lay out the subselves’ interests—roughly: kin care, mate retention, mate acquisition, status, affiliation, disease avoidance and self-protection—and give evident examples of how they make us appear to be inconsistent decision-makers. But not so: Each is in service to reproduction, and if dead ends are a hearty part of the mix, then “[m]any of our seemingly irrational biases in judgment and decision making turn out to be pretty smart on closer examination.” They account for why an African president turned down food assistance that was labeled GMO and why the peacock strategy works—also why Don Juan looks good at first flush, but canny females know that he has trouble with commitment.

Sharp, piquant science/behavioral-economics writing.