Commentary: Fairness is intuitive

Cappelen et al. (2015) open their paper, “Fairness is intuitive,” with the observation, “A key question in the social sciences is whether it is intuitive to behave in a fair manner or whether fair behavior requires active self-control” (p. 2). They purport to offer “evidence showing that fair behavior is intuitive to most people” (p. 1). Their premise is that deciding by intuition is faster than deciding by deliberation. While this premise in and on itself is rather uncontroversial—the conclusion that they draw from it is not: “Since a decision that relies on intuition is typically made faster than a decision that relies on deliberation, the response time of a fair decision relative to a selfish decision provides an important indication of the intuitiveness of fair behavior” (p. 2). This reasoning, in fact, amounts to a reverse inference fallacy1. “Intuitive” may mean “fast,” but this would not imply that “fast” means “intuitive.” However, we may ask, under which empirical conditions might we be allowed to draw the inference of “intuitive” from “fast”? Naturally, these conditions would require that “fast” rule out “deliberative.” To achieve this, we would need information beyond relative response speed alone—such as absolute decision times. And this begs the question, which range of decision times would rule out “deliberative”—or at the very least, render it improbable? Although the precise cut-off for deliberative decisions may be difficult to establish (see e.g., Schneider and Shiffrin, 1977; Posner and Rothbart, 1998), it is clear that an individual, if given a few seconds, may have sufficient time to reflect consciously—and ample time, if given more than thirty. Responses made at those speeds ought thus not be taken as “intuitive” prima facie, on the basis of the response time data alone. Unfortunately, the authors make just this mistake. Cappelen et al. (2015) find that “fair” decisions in a dictator game are faster than are “selfish” decisions, from which they infer that the fair decision is the more intuitive (e.g., Figure 2, p. 4). However, fair decisions took on average 38.4 s, and unfair decisions on average 48.5. It would seem, then, that both decision categories are fairly slow—and neither would appear unlikely to be characterized by deliberative processes. We may speculate about sources of the difference in mean response times, but intuitive as opposed to deliberative decision making is but one out of multiple possible explanations. Another explanation, for example, could be differences in degrees of deliberation. That is, individuals who deliberated more extensively might have reached a selfish decision, whereas individuals who deliberated less—but who did deliberate nonetheless—might have arrived at a fair choice. It is even possible, in this scenario, that the impulsive response is selfish—as some prior literature has suggested (e.g., Martinsson et al., 2012; Achtziger et al., 2015). The spontaneous response may then have been overruled by controlled deliberation, which might