Even the friends of a tyrant will sometimes attack him out of contempt; for the confidence which he reposes in them breeds contempt, and they think that they will not be found out.
 Aristotle, Politics (4th century BC). copy citation

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Author Aristotle
Source Politics
Topic contempt confidence
Date 4th century BC
Language English
Reference
Note Translated by Benjamin Jowett
Weblink http://classics.mit.edu/Aristotle/politics.html

Context

“and the tale may be true, if not of him, of some one else. Dion attacked the younger Dionysius because he despised him, and saw that he was equally despised by his own subjects, and that he was always drunk. Even the friends of a tyrant will sometimes attack him out of contempt; for the confidence which he reposes in them breeds contempt, and they think that they will not be found out. The expectation of success is likewise a sort of contempt; the assailants are ready to strike, and think nothing of the danger, because they seem to have the power in their hands. Thus generals of armies attack monarchs;” source