"JACK OF BOTH SIDES."
This proverb is derived from the Greek, and applied to Theramenes, who was at first a mighty stickler for the thirty tyrants' authority: but when they began to abuse it by defending such outrageous practices, no man more violently opposed it than he; and this (says Potter) got him the nick-name of "Jack of both sides," from Cothurnus, which was a kind of shoe that fitted both feet. P.T.W.