Something is required for the perfection of knowledge, that is not requisite for the perfection of love.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic perfection 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 knows something about it already in some respect, either in a general way, or in some one of its effects, or from having heard it commended, as Augustine says (De Trin. x, 1, 2) . But to have it is not to know it thus, but to know it perfectly. Reply Obj. 2: Something is required for the perfection of knowledge, that is not requisite for the perfection of love. For knowledge belongs to the reason, whose function it is to distinguish things which in reality are united, and to unite together, after a fashion, things that are distinct, by comparing one with another.” source