This study examined the emergence of the post-explanation effect. Explanations have a recursive effect on perceptions of the explained object, focusing on the perception of reality of things whose existence is ambiguous. This study also tested the hypothesis that the higher the self-evaluation of the explanation, the higher the perception of reality of existence for the explained object to clarify variables related to the effect’s magnitude. In two experiments, participants imagined and explained the purpose of use and background of developing a novel product and rated the product’s reality of existence before and after the explanation. The analysis revealed that participants in Experiment 1 who explained the cubic soccer ball rated its reality of existence higher after than before the explanation. Experiment 2 showed that among the self-evaluations, the plausibility of the explanation’s contents is related to an increase in the perception of the reality of existence. We discussed the cognitive processes that are assumed to underlie explanation bias.

This study attempted to analyze disaster prevention activities in Kuroshio Town, Kochi Prefecture, from the “Days-After” perspective, which is an attitude and way of talking about a disaster that has not yet occurred as if it has already happened. Days-After refers to a way of thinking and talking about a disaster that has not yet occurred not as a probability, but as something that will definitely happen in the future. It is a viewpoint that sees the occurrence of disasters as inevitable, and may cause people to give up on trying to prevent disasters. However, this study found that the Days-After perspective, which views the occurrence of a disaster as a certainty, transformed the residents of Kuroshio Town, who started exhibiting positive attitudes toward disaster prevention. Specifically, disaster-prevention activities in the Kaisho district of Kuroshio Town, Kochi Prefecture, including paintings about tsunamis created by the residents of Kuroshio Town, were analyzed. As a result, it was found that although there were conflicts over the assumption that a huge tsunami will occur during the process of learning that a future Nankai Trough earthquake is inevitable, the residents reflected on their own lives and rediscovered the value of daily life through the disaster-prevention activities, and imagined a future in which they survived the disaster.