Every accident is inferior to substance if we consider its being, since substance has being in itself, while an accident has its being in another
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic accident
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

“wherefore love is reckoned a virtue, rather than joy, which is an effect of love. And when virtue is described as being something ultimate, we mean that it is last, not in the order of effect, but in the order of excess, just as one hundred pounds exceed sixty. Reply Obj. 3: Every accident is inferior to substance if we consider its being, since substance has being in itself, while an accident has its being in another: but considered as to its species, an accident which results from the principles of its subject is inferior to its subject, even as an effect is inferior to its cause; whereas an accident that results from a participation of some higher nature is superior to its subject, in so far as it is a likeness of that higher nature, even as light is superior to the diaphanous body.” source