The Misshapen Mind: How the Brain's Haphazard Evolution Left Us with Self-Destructive Instincts

The human mind, we like to think, is an embodiment of perfection. For those with a religious inclination, our ability to think through issues logically, to construct narratives about our surroundings, and to recall events that happened decades earlier is proof positive of a divine hand at work. For the nonreligious, the mind is a secular miracle, an indication that, left to its own devices, evolution produces something akin to a Panglossian vision of the best outcomes in the best of all possible worlds.

Two new books beg to differ. The first, New York University psychologist Gary Marcus' Kluge: The Haphazard Construction of the Human Mind (Houghton Mifflin, April 2008) sets out to show the many ways in which the human mind is an evolutionary hodge-podge, a series of good-enough solutions to the problem of understanding and responding to our environment. The second is The Science of Fear: Why We Fear the Things We Shouldn't -- and Put Ourselves in Greater Danger (Dutton, June 2008), by the Canadian journalist Daniel Gardner.

I recommend you read them as a package. While both deal with complex psychological theories -- how memories can be triggered and manipulated and how our understanding of events is influenced by what other people think, by our existing preconceptions, and even by seemingly random factors such as the mentioning of a particular number before we're asked to provide the answer to a question -- Marcus clearly understands the psychological theories better. As a trained scientist, he's also somewhat more fluent in his explanations of why our brains are so easily influenced by irrational considerations.

A kluge, Marcus tells us, is an improvised engineering response to a problem. It is the product of a tinkerer playing around with odds and ends and creating a functional machine. That, he writes, is what the brain and its package of emotional, intellectual, and logical tools is. It is a series of good but imperfect methods for processing and acting on information, developed over hundreds of millions of years.

Evolution, in other words, produces things that work. That, Marcus argues, is the case with the brain, with how we store memories and how we respond to information. Were our memory systems better designed, they'd store and retrieve memories in the same way computers do. Instead, we rely on context to access snapshots from the past. Moving beyond memory, the logical aspect of higher thought is simply the icing on the cake, Marcus explains -- something that has evolved in an evolutionary microsecond and set up residence in the brain's frontal lobes. The older parts of the brain, call them our reptilian legacy, had much longer to mature. As a result, in many situations, especially when quick responses are demanded, they simply overwhelm our rational side, stampeding us into actions that don't really stand up to serious analysis.

Thus, we see an act of violence in the media (whether it be a single person being kidnapped and murdered, as with the 1993 celebrated Polly Klaas case in California, or mass slaughter, as with September 11), and we respond with a potpourri of inchoate fear, panic, and rage. We feel that the certainties governing our lives have been shattered. Rarely do we successfully step back and analyze the likelihood or unlikelihood of such an event impacting us.

For both Marcus and Gardner, the result is the emergence of an increasingly irrational political system, a sort of Truman Show in which reality is continually altered by an omnipresent media superstructure.

Marcus is particularly good at detailing the ways in which evolution didn't quite hit perfection when it comes to human thought processes. Whether it be in politics, in love, or in the imbibing of alcohol or narcotics, humans tend to look for short-term gratification even when, intellectually, they know their long-term interests might lie elsewhere. We're also easily influenced by what we see around us; we are willing to pay more for snacks, for example, immediately after being shown a picture of a happy face. We're more likely to cooperate with others shortly after hearing a news report about a do-gooder helping his neighbor.