Now the appetitive movement belongs rather to the order of intention than to that of execution. Wherefore love precedes hatred: because each is an appetitive movement.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic love movement
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

“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. Now the appetitive movement belongs rather to the order of intention than to that of execution. Wherefore love precedes hatred: because each is an appetitive movement. ________________________
THIRD ARTICLE [I-II, Q. 29, Art. 3]
Whether Hatred Is Stronger Than Love?
Objection 1: It would seem that hatred is stronger than love. For Augustine says (QQ. 83, qu. 36) : "There is no one who does not flee from pain, more than he desires pleasure."” source