Psychologists have documented widespread public deference to “sacred values” that communities, formally or informally, exempt from tradeoffs with secular limits, like money. This work has, however, been largely confined to low-stakes settings. As the stakes rise, deference must decline because people can't write blank checks for every “sacred” cause. Shadow pricing is inevitable which sets the stage for political blame-games of varying sophistication. In a rational world, citizens would accept the necessity of such tradeoffs, but the attraction to moral absolutes is strong--perhaps even essential for social cohesion.

Most economists define rationality in terms of consistency principles. These principles place “bounds” on rationality—bounds that range from perfect consistency to weak stochastic transitivity. Several decades of research on preferential choice has demonstrated how and when people violate these bounds. Many of these violations are interconnected and reflect systematic behavioral principles. We discuss the robustness of the violations and review the theories that are able to predict them. We further discuss the adaptive functions of the violations. From this perspective, choices do more than reveal preferences; they also reflect subtle, yet often quite reasonable, dependencies on the environment.