This column will change your life: self-perception theory

Hardly a week goes by, these days, without some psychologist uncovering more evidence that – and there's no point soft-soaping this – you don't know what the hell you're doing. More specifically: you don't know why you do what you do. According to the latest findings on the phenomenon of "priming", the mere presence of a mobile phone near where two strangers are talking makes them less likely to end up feeling positive about each other, perhaps because it triggers distracting thoughts about other friends. Research conducted in Newcastle, meanwhile, suggests that in areas where fewer elderly people are seen in the street, younger residents may subconsciously conclude that life is short, and thus fast-track their lives, for example by having children earlier. (Whether or not they're correct, fair play to the researchers for their title: No Country For Old Men.) Even our deepest convictions can be manipulated by simple trickery. In a study published last month, Swedish volunteers were asked to complete an attitudes survey on everything from internet privacy to the Middle East conflict. Then they were asked to look back and discuss their responses. But thanks to some sleight of hand, their answers now appeared beneath different questions – so it looked as if a pro-Israeli respondent, say, had given a pro-Palestinian answer. More than half proved perfectly willing to argue for the opposite of at least one position they'd originally taken: so much for deep convictions.

It's weird enough that a phone on the next table at a restaurant might reduce the chances of two people hitting it off on a date. But the Swedish study points towards something weirder: not just that we're subconsciously influenced by our environments, but that we infer our very sense of who we are from our behaviour. Normally, we assume things work the other way: that a person who thinks of herself as compassionate will therefore act compassionately. But "self-perception theory" proposes that the opposite's also true: we observe our behaviour, then reach conclusions about who we are. "After purchasing the latte, we assume that we are coffee connoisseurs," as the psychologist Timothy Wilson writes on edge.org. After returning the lost wallet, we conclude that we're honest. In reality, many pressures shape our behaviour – maybe, Wilson writes, we "returned the wallet in order to impress the people around us". But we conclude "that our behaviour emanated from some inner disposition". Or we're tricked into believing we answered a survey favouring one side of the Israeli-Palestinian conflict – and assume that must be our view.

It's tempting to conclude that we're helpless puppets of circumstance, unable ever to know ourselves. But there's an upside to self-perception theory: it supports a certain kind of "faking it till you make it", dating back to William James and revisited in Richard Wiseman's recent book, Rip It Up. If you want to think of yourself as generous – or happy or confident or patient – then act how generous people act; the self-perception will follow. (This isn't the same as trying to fool yourself you're feeling generous, happy, etc: that way lies misery.) Of course, the same goes for bad behaviour. Wilson quotes Kurt Vonnegut: "We are what we pretend to be, so we should be careful about what we pretend to be." You're constantly watching yourself. So you'd better watch yourself.

oliver.burkeman@theguardian.com

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