Hence it comes that all armed prophets have been victorious, and all unarmed prophets have been destroyed. - Niccolò Machiavelli

In this passage we are taught how hateful a thing is calumny in all free States, as, indeed, in every society, and how we must neglect no means which may serve to check it. And there can be no more effectual means for checking calumny than by affording ample facilities for impeachment, which is as useful in a commonwealth as the other is pernicious. And between them there is this difference, that calumny needs neither witness, nor circumstantial proof to establish it, so that any man may be calumniated by any other; but not impeached; since impeachment demands that there be substantive charges made, and trustworthy evidence to support them.

Quod Principi plaevit habet legis vigorem

Without an opportunity, their abilities would have been wasted, and without their abilities, the opportunity would have arisen in vain.