In chess the fool stands next to the king.
Les fous sont aux échecs les plus proches des rois.
Original text (French)
Notes from Wikiquote
This implies that it is not only at chess that the king is surrounded by fools, but at court too. Le fou is called the bishop in the English game. | De V. Payen-Payne, French Idioms and Proverbs, 4th ed. (1905), p. 130