In chess, the French call the “bishop” fou, and used to represent the piece in a fool's dress; hence, Regnier says, “Les fous sont aux échecs les plus proches des Rois” (14 Sat.). Fou is a corruption of the Eastern word Fol (an elephant), as Thomas Hyde remarks in his Ludis Orientalibus (i. 4), and on old boards the places occupied by our “bishops” were occupied by elephants.
“The ancient and noble family of Tom Fool.”
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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