“It is the peculiar quality of a fool to perceive the faults of others and to forget his own.”
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Marcus Tullius Cicero 180
Roman philosopher and statesman -106–-43 BCRelated quotes

Reflections on Various Subjects (1665–1678), VII. On Air and Manner
Context: Few men, nevertheless, can have unison in many matters without being a copy of each other, if each follow his natural turn of mind. But in general a person will not wholly follow it. He loves to imitate. We often imitate the same person without perceiving it, and we neglect our own good qualities for the good qualities of others, which generally do not suit us.

Edward A Freeman The History of the Norman Conquest of England Vol. 5 (1876) p. 579.
Criticism

The Education of Henry Adams (1907)
“Other people’s faults can be fascinating. One’s own are dreary.”
Source: Gormenghast (1950), Chapter 48 (p. 647)