Why do we so often ignore the influence of situations on behavior?

Situations matter; they have an effect on us all, great or small. We are told we should walk a mile in someone elses shoes, to look at it from my point of view, and would never dream of swearing in the principals office. So why are we so quick to judge others’ behavior as if the situations they find themselves in are irrelevant? Imagine you are walking with a friend along a crowded city street. Just up ahead, the wind starts to gust and some money floats down from a womans pocket, falling to the ground directly behind her step. A man darts from the throng of people and rushes to pick up the cash as it begins to flutter in the breeze. He looks around at the gathered crowd, and then proceeds to chase after the woman, breathlessly handing over her lost money as he catches her. She thanks him graciously, and goes about her day, perhaps later telling a friend about how lucky she was to have her money returned to her by a stranger. The rest of us, as onlookers, are left with a difficult social puzzle to solve. Why did the man give back the money?

A few competing explanations may immediately come to mind. Is he a kind man who would do that for anyone? Is he perhaps an old-fashioned man, who might do that for a pretty girl, but not for another man? Or was he just doing what any of us would have done given the surrounding crowd of onlookers? Each of these possibilities appears quite plausible at first blush, and given the rather threadbare description of the event one would imagine that people would split on which of the explanations they prefer. After all, we really have very little to go on. Curiously though, when people actually reason about stories like this they most often prefer to explain the mans behavior in terms of his traits. You might plump for him being a stickler for honesty, but you are very unlikely to think that he was just behaving how anyone would in that situation. Further, despite the complex and uncertain circumstances, these decisions are made very quickly and with great confidence.

This tendencyto assume that a person acts because of his or her dispositions, ignoring the influence of the situationhas the rather grand title of the fundamental attribution error (FAE; Ross, 1977). It describes the idea that we make attributions that are fundamental to the persons character, and that these attributions often overlook clear situational causes of behavior. Someone sitting quietly on the bus, ignoring others, might be cast as an introvert and aloof, yet the social script for bus-sitting strongly discourages loud conversation with strangers (Wesselmann et al., 2012). Theorists argue that people attribute behavior to othersdispositions spontaneously (the honest man), only correcting their attributions deliberately (we all would have done the same) if they have the time and inclination to do so (Gilbert, 1998a). Social psychologists have done very well in explaining the circumstances that give rise to this error, but a clear account of why we do this has remained elusive.

New research in social neuroscience suggests that our propensity to look to the person and not the situation for the causes of their behavior may be the result of spontaneously thinking about their mental states. Work that I and my colleagues have done suggests that the FAE might be a byproduct of humans having a highly-evolved system that takes behaviors we see and converts them into models of the underlying mental states of the actors (Moran, Jolly, and Mitchell, 2014). This work used functional magnetic resonance imaging (fMRI) to show that higher activity in brain regions associated with representing othersmental statesspecifically the medial prefrontal cortex (e.g., Amodio and Frith, 2006; Wagner et al., 2012)predicted whether participants would say that a behavior they read about was caused by the persons disposition, rather than by the situation the person found themselves in. That is, if a part of your brain specialized for thinking about othersmental states is spontaneously active when you see other peoples behavior (or read about it, in this case), you are more likely, when asked later, to explain their behavior in terms of their traits or dispositions.