The coinage story is not a metaphor the Cynics reached for — it is a criminal charge that followed Diogenes out of Sinope, and Diogenes Laertius reports that Diogenes admitted it in a lost work of his own. Defacing a coin does not destroy the metal; it destroys the authority stamped on it, which is exactly what was proposed for custom. That makes Cynicism unlike scepticism: the world is fine, and the stamp is the fraud. It also makes it unlike asceticism as a religion practises it, because there is no purity at the end of the subtraction, only accuracy.