The Temporal Discounting of Moral Judgments

When in time do people stop judging past actions by today's moral standards? Across two experiments, we tested whether and how time—ranging from today to medieval times—affects moral condemnation across a range of actions. In Experiment 1, we found that as temporal distance increased, participants were less likely to apply modern moral standards. However, highly harmful transgresions (e.g., sexual assault) showed attenuated discounting. Experiment 2 replicated and extended these findings—testing whether perceived knowledge of someone in the past explains why temporal discounting occurs. We find evidence that belief that a transgressor had knowledge of the action being a moral wrong partially explains whether people apply their current moral standards. These results suggest that people stop applying their own moral standards when evaluating the past and do so based on both harm and inferences that a person should have known the action was wrong.