But a man loves himself more than another: because he is one with himself substantially, whereas with another he is one only in the likeness of some form.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic likeness 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

“and it takes pleasure in its realization, if it be a sentient and cognitive being. Now it has been stated above (Q. 26, A. 4) , that in the love of concupiscence, the lover, properly speaking, loves himself, in willing the good that he desires. But a man loves himself more than another: because he is one with himself substantially, whereas with another he is one only in the likeness of some form. Consequently, if this other's likeness to him arising from the participation of a form, hinders him from gaining the good that he loves, he becomes hateful to him, not for being like him, but for hindering him from gaining his own good.” source