Replication of a study from “The illusion of moral decline” (Nature | Mastroianni & Gilbert 2023)

We ran a replication of Study 5b from this paper. This study tested whether people believe that morality is declining over time. The paper noted that people encounter disproportionately negative information about current-day people (e.g., via the media) and people often have weaker emotional responses to negative events from the past. As such, the authors hypothesized that participants would think people are less moral today than people used to be, but that this perception of moral decline would diminish when comparing timepoints before participants were born. To test these hypotheses, the study asked each participant to rate how “kind, honest, nice, and good” they thought people are today and were at four previous timepoints corresponding, approximately, to when participants were 20 years old, when they were born, 20 years before they were born, and 40 years before they were born.The results from the original study confirmed the authors’ predictions: Participants perceived moral decline during their lifetime, but there was no evidence of perceived moral decline for the time periods before participants were born. Our replication found the same pattern of results.The study received a transparency rating of 4.25 stars because its materials, data, and code were publicly available, but it was not pre-registered. The paper received a replicability rating of 5 stars because all of its primary findings replicated. The study received a clarity rating of 5 stars because the claims were well-calibrated to the study design and statistical results.