Abstract: The metaphor “cleanliness is next to godliness” widely exists in cultural and religious fields. Several recent empirical studies have suggested that physical cleanliness relieves one’s immoral emotions, and a clean self enhances one’s moral self image and can render harsh moral judgment. There were evidences supporting the conclusion that different parts of body involved in moral transgression tend to be cleaned. There are two theoretical explanations of the association between physical cleanliness and morality, which is the framework of conceptual metaphor theory and the embodied cognition theory. Stabilization, specificity and cross-cultural consistency of the association still need to be further explored. The present article offers several directions of future research on the threshold of the effects of physical cleanliness on moral self, the impact of different types of bodily cleansing on one’s mind, the status of physical cleanliness among the moral copings, and the integration of interdisciplinary theories.

Key words: physical cleanliness, morality, washing hand, guilt, culture