There is no fault which makes a man more unpopular, and no fault which we are more unconscious of in ourselves.
 C. S. Lewis, Mere Christianity (1952). copy citation

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Author C. S. Lewis
Source Mere Christianity
Topic fault unconscious
Date 1952
Language English
Reference
Note Adapted from a series of BBC radio talks made between 1942 and 1944
Weblink https://www.dacc.edu/assets/pdfs/PCM/merechristianitylewis.pdf

Context

“I do not think I have ever heard anyone who was not a Christian accuse himself of this vice. And at the same time I have very seldom met anyone, who was not a Christian, who showed the slightest mercy to it in others. There is no fault which makes a man more unpopular, and no fault which we are more unconscious of in ourselves. And the more we have it ourselves, the more we dislike it in others. The vice I am talking of is Pride or Self-Conceit: and the virtue opposite to it, in Christian morals, is called Humility. You may remember, when I was talking about sexual morality, I warned you that the centre of Christian morals did not lie there.” source