Kluge: The Haphazard Construction of the Human Mind

plays a huge role, whether we are speaking of something mundane, like a new car, or making decisions with lives at stake.

The trolley scenarios illustrate the split by showing how we can get two different answers to essentially the same question, depending on which system we tap into. The psychologist Jonathan Haidt has tried to go a step further, arguing that we can have strong moral intuitions even when we can’t back them up with explicit reasons. Consider, for example, the following scenario:

Julie and Mark are brother and sister. They are traveling together in France on summer vacation from college. One night they are staying alone in a cabin near the beach. They decide that it would be interesting and fun if they tried making love. At the very least it would be a new experience for each of them. Julie was already taking birth control pills, but Mark uses a condom too, just to be safe. They both enjoy making love, but they decide not to do it again. They keep that night as a special secret, which makes them feel even closer to each other. What do you think about that? Was it okay for them to make love?

Every time I read this passage, I get the creeps. But why exactly is it wrong? As Haidt describes it, most people who hear the above story immediately say that it was wrong for the siblings to make love, and they then begin searching for reasons. They point out the dangers of inbreeding, only to remember that Julie and Mark used two forms of birth control. They argue that Julie and Mark will be hurt, perhaps emotionally, even though the story makes it clear that no harm befell them. Eventually, many people say something like “I don’t know, I can’t explain it, I just know it’s wrong.”

Haidt calls this phenomenon — where we feel certain that something is wrong but are at a complete loss to explain why — “moral dumbfounding.” I call it an illustration of how the emotional and the judicious can easily decouple. What makes moral dumbfounding possible is the split between our ancestral system — which looks at an overall picture without being analytical about the details — and a judicious system, which can parse things piece by piece. As is so often the case, where there is conflict, the ancestral system wins: even though we know we can’t give a good reason, our emotional queasiness lingers.

When you look inside the skull, using neuroimaging, you find further evidence that our moral judgments derive from two distinct sources: people’s choices on moral dilemmas correlate with how they use their brains. In experimental trials like those mentioned earlier, the subjects who chose to save five lives at the expense of one tended to rely on the regions of the brain known as the dorsolateral prefrontal cortex and the posterior parietal cortex, which are known to be important for deliberative reasoning. On the other hand, people who decided in favor of the single individual at the cost of five tended to rely more on regions of the limbic cortex, which are more closely tied to emotion.[26]

What makes the human mind a kluge is not the fact that we have two systems per se but the way in which the two systems interact. In principle, a deliberative reasoning system should be, well, deliberate: above the fray and unbiased by the considerations of the emotional 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. LANGUAGE

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.

Human language may seem majestic, from the perspective of a vervet monkey confined to a vocabulary of three words (roughly, eagle, snake, and leopard). But in reality, language is filled with foibles, imperfections, and idiosyncrasies, from the way we pronounce words to the ways we put together sentences. We start, we stop, we stutter, we use like as a punctuation marker; we swap our consonants like the good Reverend William Archibald Spooner (1844-1930), who turned Shakespeare’s one fell swoop into one swell foop. (A real smart feller becomes a real… well, you get the idea.) We may say bridge of the neck when we really mean bridge of the nose; we may mishear All of the members of the group grew up in Philadelphia as All of the members of the group threw up in Philadelphia. Mistakes like these[27] are a tic of the human mind.

The challenge, for the cognitive scientist, is to figure out which idiosyncrasies are really important. Most are mere trivia, amusing but not reflective of the deep structures of the mind. The word driveway, for example, used to refer to driving on a private road that went from a main road to a house. In truth, we still drive on (or at least into) driveways, but we scarcely notice the driving part, since