A stupidity, which in a man known to be endowed with some wit, is considered as a false excuse.
 Jean-Jacques Rousseau, Confessions (1782). copy citation

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Author Jean-Jacques Rousseau
Source Confessions
Topic stupidity excuse
Date 1782
Language English
Reference
Note Translated by Samuel William Orson
Weblink https://en.wikisource.org/wiki/Confessions_(Rousseau)

Context

“She thought the reflection extremely just, and said some very sensible things upon the subject which made me blush. How was I enraged at my incredible stupidity, which has frequently given me the appearance of guilt when I was nothing more than a fool and embarrassed! A stupidity, which in a man known to be endowed with some wit, is considered as a false excuse. I can safely swear that in this kiss, as well as in the others, the heart and thoughts of Mademoiselle Amelia were not more pure than my own, and that if I could have avoided meeting her I should have done it;” source