Rhyme-as-reason effect

The rhyme-as-reason effect, also known as the Eaton–Rosen phenomenon, is a cognitive bias where sayings or aphorisms are perceived as more accurate or truthful when they rhyme.

In experiments, participants evaluated variations of sayings that either rhymed or did not rhyme. Those that rhymed were consistently judged as more truthful, even when the meaning was controlled for. For instance, the rhyming saying "What sobriety conceals, alcohol reveals" was rated as more accurate on average than its non-rhyming counterpart, "What sobriety conceals, alcohol unmasks," across different groups of subjects (each group assessed the accuracy of only one version of the statement).

This effect may be explained by the Keats heuristic, which suggests that people assess a statement's truth based on its aesthetic qualities. Another explanation is the fluency heuristic, which posits that statements are preferred due to their ease of cognitive processing.