It is always mortifying not to be believed, and it is doubly so when we suspect that it is because we are supposed to be unworthy of belief and capable of seriously and wilfully deceiving. To tell a man that he lies, is of all affronts the most mortal.
 Adam Smith, The Theory of Moral Sentiments (1759). copy citation

add
Author Adam Smith
Source The Theory of Moral Sentiments
Topic belief lie
Date 1759
Language English
Reference
Note
Weblink https://en.wikisource.org/wiki/The_Theory_of_Moral_Sentiments

Context

“Great ambition, the desire of real superiority, of leading and directing, seems to be altogether peculiar to man, and speech is the great instrument of ambition, of real superiority, of leading and directing the judgments and conduct of other people. It is always mortifying not to be believed, and it is doubly so when we suspect that it is because we are supposed to be unworthy of belief and capable of seriously and wilfully deceiving. To tell a man that he lies, is of all affronts the most mortal. 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.” source