Chi ha nimici potenti, dee per salvar se et ofTender loro, credere ferniamente due cose, verso di se contrarie; l’una che sieno arditi e prudenti, l’altra che con tutta la prudenza loro possano essi parimente errare.

Translation: He who has powerful enemies should, for his own protection and their undoing, firmly believe two things, apparently contradictory; first that they are both bold and prudent, and secondly that with all their prudence they are capable of making mistakes. | Translation reported in Harbottle's Dictionary of quotations French and Italian (1904), p. 265.