Friendship cannot exist except towards rational creatures, who are capable of returning love, and communicating one with another in the various works of life, and who may fare well or ill, according to the changes of fortune and happiness
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic friendship happiness
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/17611/pg17611-images.html

Context

“Although creatures have not existed from eternity, except in God, yet because they have been in Him from eternity, God has known them eternally in their proper natures; and for that reason has loved them, even as we, by the images of things within us, know things existing in themselves. Reply Obj. 3: Friendship cannot exist except towards rational creatures, who are capable of returning love, and communicating one with another in the various works of life, and who may fare well or ill, according to the changes of fortune and happiness; even as to them is benevolence properly speaking exercised. But irrational creatures cannot attain to loving God, nor to any share in the intellectual and beatific life that He lives. Strictly speaking, therefore, God does not love irrational creatures with the love of friendship;” source