Reply Obj. 3: The reason why we act with greater insistence in repelling what is hateful, is because we feel hatred more keenly.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic reason feeling
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

“2: Hatred would never overcome love, were it not for the greater love to which that hatred corresponds. Thus man loves himself, more than he loves his friend: and because he loves himself, his friend is hateful to him, if he oppose him.
Reply Obj. 3: The reason why we act with greater insistence in repelling what is hateful, is because we feel hatred more keenly. ________________________
FOURTH ARTICLE [I-II, Q. 29, Art. 4]
Whether a Man Can Hate Himself?
Objection 1: It would seem that a man can hate himself. For it is written (Ps. 10:6) : "He that loveth iniquity, hateth his own soul."” source