The Three Wise Monkeys
The three wise monkeys are a pictorial maxim. Together they embody the proverbial principle "to see no evil, hear no evil, and to speak no evil". The three monkeys are Mizaru (見猿), covering his eyes, who sees no evil; Kikazaru (聞か猿), covering his ears, who hears no evil; and Iwazaru (言わ猿), covering his mouth, who speaks no evil.
The source that popularized this pictorial maxim is a 17th century carving over a door of the famous Tōshō-gū shrine in Nikkō, Japan.