Moral Judgments Are (Most Probably) Robust to Physical Fatigue

Abstract

Across two experiments (N = 303), we examined the effect of physical fatigue on moral decision-making. Participants were subjected to acute physical exercise. Half of the participants were presented with moral dilemmas before the physical exercise and the other half after the exercise. We measured moral judgement using a shortened version of the Process Dissociation procedure, allowing us to investigate (1) decisions in the traditional sacrificial dilemmas and (2) deontological and utilitarian moral inclinations. The results showed no significant differences in moral judgments between fatigued and nonfatigued participants in nine out of 10 statistical tests. This suggests a unique resilience of moral judgments to physical fatigue, in contrast to what is known about cognitive fatigue.

Keywords: fatigue; moral decision-making; morality; physical fatigue; process dissociation.