Kluge: The Haphazard Construction of the Human Mind (Houghton Mifflin; 2008)

In principle, an organism that trafficked in beliefs ought to have a firm grasp on the origins of its beliefs and how strongly the evidence supports them. Does my belief that Colgate is a good brand of toothpaste derive from (1) my analysis of a double-blind test conducted and published by Consumer Reports, (2) my enjoyment of Colgate's commercials, or (3) my own comparisons of Colgate against the other "leading brands"? I shouldbe able to tell you, but I can't.

*Animals often behave as if they too have beliefs, but scientific and philosophical opinion remains divided as to whether they really do. My interest here is the sort of belief that we humans can articulate, such as "On rainy days, it is good to carry an umbrella" or "Haste makes waste." Such nuggets of conventional wisdom aren't necessarily true (if you accept "Absence makes the heart grow fonder," then what about "Out of sight, out of mind"?), but they differ from the more implicit "beliefs" of our sensorimotor system, which we cannot articulate. For example, our sensorimotor system behaves as if it believes that a certain amount of force is sufficient to lift our legs over a curb, but nonphysicists would be hard pressed to say how much force is actually required.) I strongly suspect that many animals have this sort of implicit beliefs, but my working assumption is that beliefs of the kind that we can articulate, judge, and reflect upon are restricted to humans and, at most, a handful of other species.

Because evolution built belief mainly out of off-the-shelf components that evolved for other purposes, we often lose track of where our beliefs come from — if we ever knew — and even worse, we are often completely unaware of how much we are influenced by irrelevant information.

Take, for example, the fact that students rate better-looking professors as teaching better classes. If we have positive feelings toward a given person in one respect, we tend to automatically generalize that positive regard to other traits, an illustration of what is known in psychology as the "halo effect." The opposite applies too: see one negative characteristic, and you expect all of an individual's traits to be negative, a sort of "pitchfork effect." Take, for example, the truly sad study in which people were shown pictures of one of two children, one more attractive, the other less so. The subjects were then told that the child, let's call him Junior, had just thrown a snowball, with a rock inside it, at another child; the test subjects then were asked to interpret the boy's behavior. People who saw the unattractive picture characterized Junior as a thug, perhaps headed to reform school; those shown the more attractive picture delivered judgments that were rather more mild, suggesting, for example, that Junior was merely "having a bad day." Study after study has shown that attractive people get better breaks in job interviews, promotions, admissions interviews, and so on, each one an illustration of how aesthetics creates noise in the channel of belief.

In the same vein, we are more likely to vote for candidates who (physically) "look more competent" than the others. And, as advertisers know all too well, we are more likely to buy a particular brand of beer if we see an attractive person drinking it, more likely to want a pair of sneakers if we see a successful athlete like Michael Jordan wearing them. And though it may be irrational for a bunch of teenagers to buy a particular brand of sneakers so they can "be like Mike," the halo effect, ironically, makes it entirely rational for Nike to spend millions of dollars to secure His Airness's endorsement. And, in a particularly shocking recent study, children of ages three to five gave have higher ratings to foods like carrots, milk, and apple juice if they came in McDonald's packaging. Books and covers, carrots and Styrofoam packaging. We are born to be suckered.