Adam Smith, The Theory of Moral Sentiments:
Common looking-glasses, it is said, are extremely deceitful, and by the glare which they throw over the face, conceal from the partial eyes of the person many deformities which are obvious to every body besides. But there is not in the world such a smoother of wrinkles as is every man’s imagination, with regard to the blemishes of his own character.
In fairness to Smith, this passage appears only in the first edition of TMS; it was excised from the succeeding five editions that appeared in his lifetime. It’s also quite out of keeping with the overall thrust of the text, particularly its lengthy passages on the torment we subject ourselves to when we act in ways we believe are less than praiseworthy, even if everyone else believes the contrary.