Do you know why you hired your most recent employee over the runner-up? Do you know why you bought your last pair of pajamas? Do you know what makes you happy and unhappy?
Don't be too sure. The most important thing that social psychologists have discovered over the last 50 years is that people are very unreliable informants about why they behaved as they did, made the judgment they did, or liked or disliked something. In short, we don't know nearly as much about what goes on in our heads as we think. In fact, for a shocking range of things, we don't know the answer to "Why did I?" any better than an observer.
The first inkling that social psychologists had about just how ignorant we are about our thinking processes came from the study of cognitive dissonance beginning in the late 1950s. When our behavior is insufficiently justified, we move our beliefs into line with the behavior so as to avoid the cognitive dissonance we would otherwise experience. But we are usually quite unaware that we have done that, and when it is pointed out to us we recruit phantom reasons for the change in attitude.
Beginning in the mid-1960s, social psychologists started doing experiments about the causal attributions people make for their own behavior. If you give people electric shocks, but tell them that you have given them a pill that will produce the arousal symptoms that are actually created by the shock, they will take much more shock than subjects without the pill. They have attributed their arousal to the pill and are therefore willing to take more shock. But if you ask them why they took so much shock they are likely to say something like "I used to work with electrical gadgets and I got a lot of shocks, so I guess I got used to it."
In the 1970s social psychologists began asking whether people could be accurate about why they make truly simple judgments and decisions — such as why they like a person or an article of clothing.
For example, in one study experimenters videotaped a Belgian responding in one of two modes to questions about his philosophy as a teacher: he either came across as an ogre or a saint. They then showed subjects one of the two tapes and asked them how much they liked the teacher. Furthermore, they asked some of them whether the teacher's accent had affected how much they liked him and asked others whether how much they liked the teacher influenced how much they liked his accent. Subjects who saw the ogre naturally disliked him a great deal, and they were quite sure that his grating accent was one of the reasons. Subjects who saw the saint realized that one of the reasons they were so fond of him was his charming accent. Subjects who were asked if their liking for the teacher could have influenced their judgment of his accent were insulted by the question.
Does familiarity breed contempt? On the contrary, it breeds liking. In the 1980s, social psychologists began showing people such stimuli as Turkish words and Chinese ideographs and asking them how much they liked them. They would show a given stimulus somewhere between one and twenty-five times. The more the subjects saw the stimulus the more they liked it. Needless to say, their subjects did not find it plausible that the mere number of times they had seen a stimulus could have affected their liking for it. (You're probably wondering if white rats are susceptible to the mere familiarity effect.
The study has been done. Rats brought up listening to music by Mozart prefer to move to the side of the cage that trips a switch allowing them to listen to Mozart rather than Schoenberg. Rats raised on Schoenberg prefer to be on the Schoenberg side. The rats were not asked the reasons for their musical preferences.)
Does it matter that we often don't know what goes on in our heads and yet believe that we do? Well, for starters, it means that we often can't answer accurately crucial questions about what makes us happy and what makes us unhappy. A social psychologist asked Harvard women to keep a daily record for two months of their mood states and also to record a number of potentially relevant factors in their lives including amount of sleep the night before, the weather, general state of health, sexual activity, and day of the week (Monday blues? TGIF?). At the end of the period, subjects were asked to tell the experimenters how much each of these factors tended to influence their mood over the two month period. The results? Women's reports of what influenced their moods were uncorrelated with what they had reported on a daily basis. If a woman thought that her sexual activity had a big effect, a check of her daily reports was just as likely to show that it had no effect as that it did. To really rub it in, the psychologist asked her subjects to report what influenced the moods of someone they didn't know: She found that accuracy was just as great when a woman was rated by a stranger as when rated by the woman herself!
But if we were to just think really hard about reasons for behavior and preferences might we be likely to come to the right conclusions?
Actually, just the opposite may often be the case. A social psychologist asked people to choose which of several art posters they liked best.
Some people were asked to analyze why they liked or disliked the various posters and some were not asked, and everyone was given their favorite poster to take home. Two weeks later the psychologist called people up and asked them how much they liked the art poster they had chosen. Those who did not analyze their reasons liked their posters better than those who did.
It's certainly scary to think that we're ignorant of so much of what goes on in our heads, though we're almost surely better off taking with a large quantity of salt what we and others say about motives and reasons. Skepticism about our ability to read our minds is safer than certainty that we can.
Still, the idea that we have little access to the workings of our minds is a dangerous one. The theories of Copernicus and Darwin were dangerous because they threatened, respectively, religious conceptions of the centrality of humans in the cosmos and the divinity of humans.
Social psychologists are threatening a core conviction of the Enlightenment — that humans are perfectible through the exercise of reason. If reason cannot be counted on to reveal the causes of our beliefs, behavior and preferences, then the idea of human perfectibility is to that degree diminished.