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

system. A sensibly designed deliberative-reasoning machine would systematically search its memory for relevant data, pro and con, so that it could make systematic decisions. It would be attuned as much to disconfirmation as confirmation and utterly immune to patently irrelevant information (such as the opening bid of a salesperson whose interests are necessarily different from your own). This system would also be empowered to well and truly stifle violations of its master plan. ("I'm on a diet. No chocolate cake. Period.") What we have instead falls between two systems — an ancestral, reflexive system that is only partly responsive to the overall goals of the organism, and a deliberative system (built from inappropriate old parts, such as contextual memory) that can act in genuinely independent fashion only with great difficulty.

Does this mean that our conscious, deliberate choices are always the best ones? Not at all. As Daniel Kahneman has observed, the reflexive system is better at what ztdoes than the deliberative system is at deliberating. The ancestral system, for example, is exquisitely sensitive to statistical fluctuations — its bread and butter, shaped over eons, is to track the probabilities of finding food and predators in particular locations. And while our deliberative system can be deliberate, it takes a great deal of effort to get it to function in genuinely fair and balanced ways. (Of course, this is no surprise if you consider that the ancestral system has been shaped for hundreds of millions of years, but deliberative reasoning is still a bit of a newfangled invention.)

So, inevitably, there are decisions for which the ancestral system is better suited; in some circumstances it offers the only real option. For instance, when you have to make a split-second decision

— whether to brake your car or swerve into the next lane — the deliberative system is just too slow. Similarly, where we have many different variables to consider, the unconscious mind — given suitable time — can sometimes outperform the conscious deliberative mind; if your problem requires a spreadsheet, there's a chance that the ancestral, statistically inclined mind might be just the ticket. As Malcolm Gladwell said in his recent book Blink, "Decisions made very quickly can be every bit as good as decisions made consciously and deliberately."

Still, we shouldn't blindly trust our instincts. When people make effective snap decisions, it's usually because they have ample experience with similar problems. Most of Gladwell's examples, like that of an art curator who instantly recognizes a forgery, come from experts, not amateurs. As the Dutch psychologist Ap Dijksterhuis, one of the world's leading researchers on intuition, noted, our best intuitions are those that are the result of thorough unconscious thought, honed by years of experience. Effective snap decisions (Gladwell's "blinks") often represent the icing on a cake that has been baking for a very long time. Especially when we face problems that differ significantly from those that we've faced before, deliberative reasoning can be our first and best hope.

It would be foolish to routinely surrender our considered judgment to our unconscious, reflexive system, vulnerable and biased as it often is. But it would be just as silly to abandon the ancestral reflexive system altogether: it's not entirely irrational, just less reasoned. In the final analysis, evolution has left us with two systems, each with different capabilities: a reflexive system that excels in handling the routine and a deliberative system that can help us think outside the box.

Wisdom will come ultimately from recognizing and harmonizing the strengths and weaknesses of the two, discerning the situations in which our decisions are likely to be biased, and devising strategies to overcome those biases.

5

LANG UAG E

One morning I shot an elephant in my pajamas. How he got into my pajamas I'll never know.

— GROUCHO MARX

SHE SELLS SEASHELLS by the seashore. A pleasant peasant pheasant plucker plucks a pleasant pheasant. These are words that twist the tongue.