But hatred and love differ according to the difference of good and evil. Therefore love is stronger than hatred.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic evil love
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/17897/pg17897-images.html

Context

“But man insists more on repelling what is hateful, than on seeking what is pleasant: thus also irrational animals refrain from pleasure for fear of the whip, as Augustine instances (QQ. 83, qu. 36). Therefore hatred is stronger than love.
On the contrary, Good is stronger than evil; because "evil does nothing except in virtue of good," as Dionysius says (Div. Nom. iv) . But hatred and love differ according to the difference of good and evil. Therefore love is stronger than hatred. I answer that, It is impossible for an effect to be stronger than its cause. Now every hatred arises from some love as its cause, as above stated (A. 2). Therefore it is impossible for hatred to be stronger than love absolutely.
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