It is... a just political maxim, that every man must be supposed a knave.

Weakness, fear, melancholy, together with ignorance, are the true sources of superstition. Hope, pride, presumption, a warm indignation, together with ignorance, are the true sources of enthusiasm.

There is no such thing as freedom of choice unless there is freedom to refuse.

For, besides, that many persons find too sensible an interest in perpetually recalling such topics; besides this, I say, the motive of blind despair can never reasonably have place in the sciences; since, however unsuccessful former attempts may have proved, there is still room to hope, that the industry, good fortune, or improved sagacity of succeeding generations may reach discoveries unknown to former ages.

Heaven and hell suppose two distinct species of men, the good and the bad. But the greatest part of mankind float betwixt vice and virtue.

I am apt to suspect the Negroes to be naturally inferior to the Whites. There scarcely ever was a civilization of their complexion, nor even any individual, eminent either in action or speculation.

All sentiment is right; because sentiment has a reference to nothing beyond itself, and is always real, wherever a man is conscious of it. But all determinations of the understanding are not right; because they have a reference to something beyond themselves, to wit, real matter of fact; and are not always conformable to that standard.