Free Caveman Logic: The Persistence of Primitive Thinking in a Modern World by Hank Davis Page A

look very bad. Heuristics and the cognitive architecture that supports them have evolved because on balance they provided our ancestors with a reproductive advantage. Those who had them and used them tended to do better than those who did not. Natural selection does not demand perfection or a 100 percent success rate. A small net benefit is enough to entrench a trait in a population. In addition, most heuristics are highly situation specific. They work very well under certain conditions. When those conditions are not exactly met, the same heuristic can be triggered and lead to a lot of trouble. Whether the individual sees the error and adjusts his or her approach or continues to hammer away, producing faulty or even disastrous results in the bargain, is anybody’s guess. Too often, the latter occurs. Such events can reduce individual welfare or compromise the foreign policy of a nation.
    Arguably, heuristics are a form of intellectual laziness. The irony is that our species got to be what it is today by being intellectually lazy. We’ve already noted that there is no greater efficiency expert than natural selection. Had our ancestors spent their full intellectual resources on every problem they faced, it would have been a recipe for disaster. The winners in the race to survival and reproduction were the intellectually lazy among us who could fall back on the heuristics they carried.
    The range of situations in which these shortcuts are brought into play—not always successfully—is staggering. There is almost no area of human function where we do not call upon a social, intellectual, or perceptual heuristic to do the bulk of our work. Worse yet, we are rarely aware that we are using them, so ingrained are they in how we function. We look at a sea of colors and textures and decide it is a roomful of friends; we hear a sequence of auditory stimuli of particular pitch, phrasing, and timbre and recognize it as a song from our teenage years. We meet a stranger and decide that he or she is someone we would rather avoid than seek further contact with. We shop for a place to live and know instantly that this is The One. In each case we have chosen to devalue or ignore most of the information available to us. Our nervous systems are programmed to zero in on a tiny number of salient features and discount almost everything else.
    Heuristics have a checkered history within psychology. Do they represent the best of our minds, maximizing information and minimizing effort, or are they examples of mental sloppiness? If Introductory Psychology textbooks are any indication, the answer is mostly the latter. Virtually every textbook published in the past twenty years contains a section that paints heuristics not as commendable shortcuts, but rather as lamentable laziness. The most commonly criticized examples are called the availability heuristic and the representativeness heuristic. Both are typically treated with contempt for the errors they lead to when the real world is turned upside down in the unnatural conditions of the psychology lab. Imagine yourself encountering an unkempt individual wearing a tattered and torn jacket and smelling rather ripe. Would you have trouble identifying him as a bank president? You bet you would. Why? Because in your experience bank presidents don’t look (or smell) that way. Is this evidence of defective processing on your part? Yes, according to some, because the dreaded representativeness heuristic has gotten in the way of your ability to gather and evaluate evidence more fully.
    I want to be clear that I am not arguing for the abandonment of heuristics. Even if it were possible, it would be ill advised. Gigerenzer and Todd’s book called Simple Heuristics That Make Us Smart 4 is at the forefront of an emerging literature praising that head full of shortcuts. Many readers celebrate the idea that we can be smart and effective without being strictly rational. Gerd Gigerenzer’s book Gut Feelings is