Even Monkeys Fall Out Of Trees

猿も木から落ちる (saru mo ki kara ochiru): even monkeys fall out of trees. The expert fails at the very thing they are expert in. The proverb cuts two ways: an Edo joke-book of 1718 uses it to say do not relax where you are good, and the modern dictionaries use it to forgive an ordinary slip. It was already a saying when a haikai poet punned on it in 1638, and it is the Japanese proverb an English reader is most likely to know; two English collections took it as their title in 1987.