The man who had the misfortune to imagine that nobody believed a single word he said, would feel himself the outcast of human society, would dread the very thought of going into it, or of presenting himself before it, and could scarce fail, I think, to die of despair. It is probable, however, that no man ever had just reason to entertain this humiliating opinion of himself.
 Adam Smith, The Theory of Moral Sentiments (1759). copy citation

Context

“But whoever seriously and wilfully deceives is necessarily conscious to himself that he merits this affront, that he does not deserve to be believed, and that he forfeits all title to that sort of credit from which alone he can derive any sort of ease, comfort, or satisfaction, in the society of his equals. The man who had the misfortune to imagine that nobody believed a single word he said, would feel himself the outcast of human society, would dread the very thought of going into it, or of presenting himself before it, and could scarce fail, I think, to die of despair. It is probable, however, that no man ever had just reason to entertain this humiliating opinion of himself. The most notorious liar, I am disposed to believe, tells the fair truth at least twenty times for once that he seriously and deliberately lies; and, as in the most cautious the disposition to believe is apt to prevail over that to doubt and distrust;” source