Reply Obj. 1: A thing is a cause of love in two ways: first, as being the reason for loving. In this way good is the cause of love, since each thing is loved according to its measure of goodness.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic goodness love
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/18755/pg18755-images.html

Context

“Therefore God ought to be loved chiefly and before all out of charity: for He is loved as the cause of happiness, whereas our neighbor is loved as receiving together with us a share of happiness from Him.
Reply Obj. 1: A thing is a cause of love in two ways: first, as being the reason for loving. In this way good is the cause of love, since each thing is loved according to its measure of goodness. Secondly, a thing causes love, as being a way to acquire love. It is in this way that seeing is the cause of loving, not as though a thing were lovable according as it is visible, but because by seeing a thing we are led to love it.” source