Thus love of one thing is the cause of one's hating its contrary.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic love hate
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: Love and hatred are contraries if considered in respect of the same thing. But if taken in respect of contraries, they are not themselves contrary, but consequent to one another: for it amounts to the same that one love a certain thing, or that one hate its contrary. Thus love of one thing is the cause of one's hating its contrary. Reply Obj. 3: In the order of execution, the turning away from one term precedes the turning towards the other. But the reverse is the case in the order of intention: since approach to one term is the reason for turning away from the other.” source