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Surprising Science

Exploring the Post-Rational 21st Century

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When Adam Smith wrote that butchers, brewers and bakers worked efficiently out of “regard for their own interest,” he was doing more than asserting that self-interest could be good. He was also asserting that self-interest — a long-lasting, fact-based, explicit sense of “what’s good for me” — is possible. His Enlightenment-era model of the mind helped spawn Rational Economic Man, that being who is supposed to consciously and consistently perceive his own needs and wants, relate those to possible actions, reason his way through the options, and then act according to those calculations.

Rational Economic Man has taken quite an intellectual beating since certain financial events that I don’t need to rehearse here. But it (it’s not really a he, is it?) remains the basis for all the important institutions of society, from courts (where we assume that judges and juries can think “objectively” about a case) to medicine (where people are supposed to choose clearly among scientifically-tested options for treatment to elections (where voters are presumed to be weighing “the issues” and picking the candidate who best fits their interests. It is because we are supposed to be rational that governments guarantee our human rights: To be enlightened, Immanuel Kant explained, one must “use one’s understanding without guidance,” and this is impossible without freedom of speech and of thought. The presumption that we’re rational — at least when we’re at our best and most human — is the glue that holds global society together.


That’s probably why we 21st-century people have such respect for science (so important in our culture that even people who hate science’s version of the world feel obligated to use its language, referring not to “creation” but “creation science” when they want to deny evolution). Science is, after all, the ultimate collection of methods for creating knowledge by rational means.

It’s ironic, then — historically, colossally ironic — that science is killing off Rational Economic Man. But it is: The data comes from “hard” sciences, from social science, and often from novel combinations of the two, like neuromarketing and neuroeconomics. Some of these fields are more rigorous and prestigious than others, but in they’re all using the same fundamental method — data-based, systematic, value-neutral — to investigate the mind. And in evolutionary biology, cognitive science, social psychology, neurobiology, marketing studies, economics and many other disciplines, the scientific method is revealing that Rational Economic Man is indefensible, misguided and wrong.

Of course, no one ever claimed that human beings were purely reasoning robots. But rationality was supposed to capture the essential facts of people’s behavior, with the mess of emotion and influence relegated to a cabinet of anecdotes and oddities. Today, though, evidence is pouring in that in real life, the moments of explicit, logical calculation are the oddities. We aren’t good at stating our reasons for our actions, it seems, because most of the causes of our behavior are outside our awareness. And the rules that govern there aren’t those of logic.

People’s perceptions and choices are governed instead by innate predispositions (which tell us that an 80 percent success rate is a good bet but that a 1 in 5 failure rate is too risky, even though logically those are the same). People are highly subject to their sense of status and the responses of other people; that we’re often moved by incidental, irrelevant perceptions when we make decisions. And our supposedly well-pondered individual decisions can often be predicted by tools of analysis that don’t see individuals at all, instead detecting patterns across time. What becomes of our assumptions about rational medicine when, as Dan Ariely showed, the same pills reduce pain more when patients think they’re expensive than when they think the medicine is cheap? What theory of democracy can live with the knowledge that people can pick the winners of unknown elections just by looking at the faces of the candidates? Or that people are more likely to vote to raise education taxes if they happen to be casting ballots in a school than in a firehouse? And how are trials supposed to be conducted when we know how easily “eyewitnesses” can be persuaded to see and unsee things.

I think the science of human behavior has entered the post-rational era. And that’s what this blog is about: Why people perceive, feel, think and act as they do, and the gaps between what research says and what we think. I’m especially interested in where such knowledge leaves the institutions that we live by.

So “Mind Matters,” as I see it, include fMRI studies on why people buy stuff; arguments about how perceptions of Vietnam shape policies in Afghanistan; the contrast between what “everybody knows” and what real research finds — and many other subjects that tell us we shouldn’t ever be satisfied to say “we know this.” Because to really know anything, you have to understand how you know it.

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