To good temper we oppose the excess rather than the defect; for not only is it commoner since revenge is the more human) , but bad-tempered people are worse to live with.
 Aristotle, Nicomachean Ethics (c. 334 BC - 330 BC). copy citation

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Author Aristotle
Source Nicomachean Ethics
Topic revenge excess
Date c. 334 BC - 330 BC
Language English
Reference
Note Translated by W. D. Ross
Weblink http://classics.mit.edu/Aristotle/nicomachaen.mb.txt

Context

“Such people are most troublesome to themselves and to their dearest friends. We call had-tempered those who are angry at the wrong things, more than is right, and longer, and cannot be appeased until they inflict vengeance or punishment. To good temper we oppose the excess rather than the defect; for not only is it commoner since revenge is the more human) , but bad-tempered people are worse to live with. What we have said in our earlier treatment of the subject is plain also from what we are now saying; viz. that it is not easy to define how, with whom, at what, and how long one should be angry, and at what point right action ceases and wrong begins.” source