"Machiavelli is the first important political realist... The three essential tenets implicit in Machiavelli's doctrine are the foundation-stones of the realist philosophy. In the first place, history is a sequence of cause and effect, whose course can be analysed and understood by intellectual effort, but not (as the utopians believe) directed by "imagination". Secondly, theory does not (as the utopians assume) create practice, but practice theory. In Machiavelli's words, "good counsels, whencesoever they come, are born of the wisdom of the prince, and not the wisdom of the prince from good counsels". Thirdly, politics are not (as the utopians pretend) a function of ethics, but ethics of politics. Men "are kept honest by constraint". Machiavelli recognised the importance of morality, but thought that there could be no effective morality where there was no effective authority. Morality is the product of power. The extraordinary vigour and vitality of Machiavelli's challenge to orthodoxy may be attested by the fact that, more than four centuries after he wrote, the most conclusive way of discrediting a political opponent is still to describe him as a disciple of Machiavelli. Bacon was one of the first to praise him for "saying openly and without hypocrisy what men are in the habit of doing, not what they ought to do"."