The Evolution of Moral Development

Abstract

The goal of this chapter is to explore the developmental origins of fairness. To do so, it first describes the relationship between fairness in particular and moral psychology in general. Recent evolutionary accounts of moral psychology have placed a particular emphasis on fairness, due to its importance in governing cooperative interactions between non-kin. Applying this account to development can explain otherwise peculiar features of how fairness emerges over childhood, most notably a “knowledge-behavior gap” in which children understand many features of fairness before they are motivated to behave in compliance with those features. Specifically, merely evaluating others is low-cost and has clear benefits even in infancy (e.g., it influences who we choose to learn from), but costly prosocial behavior is typically beneficial only at later ages, when a reputation for fairness becomes increasingly important for being included rather than shunned for mutually beneficial interactions with others.