“This, too, is but a branch of our moral duties, which are generally divided into duties to God and duties to man. If we did a good act merely from the love of God and a belief that it is pleasing to Him, whence arises the morality of the Atheist? It is idle to say, as some do, that no such being exists. We have the same evidence of the fact as of most of those we act on, to-wit: their own affirmations, and their reasonings in support of them. I have observed, indeed, generally, that while in protestant countries the defections from the Platonic Christianity of the priests is to Deism, in catholic countries they are to Atheism. Diderot, D’Alembert, D’Holbach, Condorcet, are known to have been among the most virtuous of men. Their virtue, then, must have had some other foundation than the love of God.” — Thomas Jefferson letter to Thomas Law Poplar Forest, June 13, 1814.
A good point to be sure.