Personality explanations are incomplete
Second, ordinary people underestimate—or never even consider—the power of situations. That is what makes social psychology fun. Researchers can set up studies that manipulate the social situation in tiny ways that have a huge impact on people’s behavior. For example, an event as trivial as finding a coin in a public place can make people more helpful to the next stranger they meet. Many years ago, researchers planted dimes in the coin-return slot of public phones in San Francisco and Philadelphia shopping malls. The next caller almost invariably checked the coin-return slot, retrieved the coin, and emerged to find a woman walking in the same direction; the woman dropped a manila folder full of papers in the caller’s path. In the control condition, others did not find a planted dime but did encounter the same woman.
The critical measure was the number of people helping, depending on whether or not they had just found a dime. Of those who did not find a dime, only 4% (1 of 25) helped the woman pick up her spilled belongings. Of those who had just found the dime, fully 88% helped (Isen & Levin, 1972). The implied presence of another person (the one leaving the coin) and the utility of a coin as part of an imagined social exchange (buying something) created a social situation that influenced individual behavior.
Why should an event as tiny as finding a bit of change make people’s behavior so decidedly different? An observer of the behavior would doubtless say that the person is helpful or generous (a trait description). If a social psychologist said, “This person is helping because she just found a coin in the phone booth,” the observer would not believe it. The impact of this tiny feature of the social situation is counterintuitive; the power of situational happenstance flies against what people think would occur. Try asking a friend what percentage of people would normally help, and then ask the friend how much the percentage would increase if the person had just picked up a coin. I’ll wager your friend will not give odds of 5% versus 90%, as the data indicate. In short, people are biased to underestimate the power of situations.
A third reason why social psychologists emphasize situations rather than personality in explaining behavior is that, as scientists, they know that personality is complex enough to require its own separate subfield, with its own methods. Personality theorists sometimes disagree about how to measure personality. Nonscientists think personality is easy to assess, so they routinely use it to predict and explain behavior. But from a scientific perspective, personality defies easy measurement, which explains why it requires a separate field. Personality psychologists focus on accurately measuring individual differences and their implications for behavior. Measuring helpfulness—or any other aspect of personality—is not easy; even personality psychologists cannot always agree. Despite considerable progress, personality assessment still generates intense debates (Cervone, 2005; Funder, 2001; Mischel, 2004; Ozer & Benet-Martinez, 2006). Social psychologists choose to bite off a different piece of the problem, because one cannot study everything at once.
The fourth point is that laypeople’s relying on personality instead of situations is not exactly a mistake; explanations based solely on personality are simply incomplete. Personality cannot be the whole explanation for behavior because it does not usually predict specific behavior in one random situation. Some social-personality psychologists (e.g., Mendoza-Denton, Ayduk, Mischel, Shoda, & Testa, 2001; Snyder, 2006) have demonstrated that the combination of situation and personality can predict behavior. Others (Ajzen & Fishbein, 2005; Epstein, 1980) have proposed looking at personality as predicting average behavior, aggregated across situations (and therefore downplaying any particular situation). In both cases, the point is that ordinary people’s strategy of predicting one particular, specific behavior just from someone’s general personality is misguided. Either one must think of the person in a specific situation to predict a specific behavior, or one must think of a person’s overall personality as predicting an average pattern of behavior across situations. Both solutions acknowledge the joint power of personality and situations.
As scientists, social psychologists have opted to explain behavior more in terms of the social situation precisely because the role of the social situation is so often underestimated. This book aims to convince you of the adaptive significance of the social situation, that is, other people.
The Power of Situations as an Evolutionary Adaptation
Why does the social situation matter so much? Because social situations are so powerful, we need to understand why people so readily respond to them. Situations matter because people need other people in order to survive and thrive. Evolution has an important role to play in explaining the impact of social situations on people. People attune to social situations for functional, adaptive reasons. This book argues that people respond to other people and seek social acceptance through social motives that have evolved to help them survive and thrive in groups—and more generally. The power of social situations may be one of people’s most important evolutionary adaptations.
But before we examine this approach more closely, a note of caution: Evolutionary explanations can easily be misused. For example, some writers (e.g., Rushton, 1992) have implied the existence of “inferior” and “superior” races and claimed that environmental challenge creates evolutionary pressures that result in genetically based racial differences in intelligence. Rushton also alleges that sex differences in brain size determine intelligence. Similarly, men have historically held more power than women, so some writers (e.g., Goldberg, 1973; Pratto, Sidanius, & Stallworth, 1993) might argue that patriarchy has inevitably evolved because of male and female biological differences.
This kind of biological determinism weakens some evolutionary explanations because they fail to acknowledge the integral role of social factors (Maccoby, 1973, 2000; Wood & Eagly, 2002). Moreover, determinism suggests to some critics that the current evolutionary outcomes were inevitable. Evolutionary explanations can be misused to justify the status quo, as if humans were not still evolving and as if change were not part of evolution. People also think that evolutionary pressures minimize the importance of culture, but as this chapter discusses, evolution predisposes people to participate in their culture.
Despite such problems, scientists generally agree that selective pressures clearly operate on human behavior, including social behavior. Consequently, theories based on principles of selection require empirical testing. Evolutionary psychology focuses on the inherited design of the mind, especially functions that improved our ancestors’ success in passing on their genes (Buss, 2005). Evolutionary social psychology focuses on the parallel implications for social reactions (Schaller, Simpson, & Kenrick, 2006).
Various theorists have described evolutionary pressures at various levels, and this section considers four (see Table 1.3) that help us locate the relevant level for responsiveness to the social situation. First, when people think of evolution, they usually think about Darwin’s classical theory of natural selection or “survival of the fittest”: The strongest, wiliest, best-adapted individual survives to reproduce and thus to pass on his or her strong, wily, well-adapted genes. That was Charles Darwin’s original idea. It focuses on the selfish reproductive ambitions of individuals and their genes.