A good example of this eclecticism is his treatment of Mandeville, an author from whom Smith no less than Rousseau derived many fruitful ideas. In the first edition of _The Moral Sentiments_ (p. 474) he writes:— “There are, however, some other systems which seem to take away altogether the distinction between vice and virtue, and of which the tendency is upon that account wholly pernicious: I mean the systems of the Duke of Rochefoucauld and Dr. Mandeville. Though the notions of both these authors are in almost every respect erroneous, there are, however, some appearances in human nature which, when viewed in a certain manner, seem at first sight to favour them. These, first slightly sketched out with the elegance and delicate precision of the Duke of Rochefoucauld, and afterwards more fully represented with the lively and humorous, though coarse and rustic, eloquence of Dr. Mandeville, have thrown upon their doctrine an air of truth and probability which is very apt to impose upon the unskilful.” Bishop Butler, more justly, classed Rochefoucauld with Hobbes. But in Smith’s sixth edition (1790) the name of Rochefoucauld was omitted, at the instance of the Duke’s grandson, who pointed out that the author of the Maxims is not really in the same category with Mandeville. Coarse and licentious, but entertaining and ingenious, the author of the _Fable of the Bees_ hit human nature hard. He traced virtuous actions to vanity, and whittled away the distinction between vice and virtue, until he reached the paradox that private vices are public benefits. But this profligate system could never have caused so much stir and alarm in the world “had it not in some respects bordered upon the truth.” We are very easily imposed upon by the most absurd travellers’ tales about distant countries. But falsehoods about the parish we live in must, if they are to deceive us, bear some resemblance to the truth, nay, “must even have a considerable mixture of truth in them.” A natural philosopher has an analogous advantage over the speculator in ethics. The vortices of Descartes passed for nearly a century as a most satisfactory account of the revolutions of heavenly bodies, though they neither existed nor could possibly exist, and though if they did exist they could not produce such effects as were ascribed to them. But the moral philosopher is no better off than the parish liar. He is giving an account of things that are constantly before us, around us, and within us. “Though here, too, like indolent masters who put their trust in a steward that deceives them, we are very liable to be imposed upon, yet we are incapable of passing any account which does not preserve some little regard to the truth.”