Perfection of knowledge, on the part of the thing known, depends on the medium; but as regards the knower, it depends on the power or habit. And hence it is that even amongst men one sees a conclusion in a medium more perfectly than another does.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic perfection power
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/19950/pg19950-images.html

Context

“And therefore more perfectly than the rest of creatures it sees the First Truth itself, which is the Essence of God; hence it is written (John 1:14) : "And we saw His glory, the glory as it were of the Only-begotten of the Father," "full" not only of "grace" but also of "truth." Reply Obj. 1: Perfection of knowledge, on the part of the thing known, depends on the medium; but as regards the knower, it depends on the power or habit. And hence it is that even amongst men one sees a conclusion in a medium more perfectly than another does. And in this way the soul of Christ, which is filled with a more abundant light, knows the Divine Essence more perfectly than do the other blessed, although all see the Divine Essence in itself. Reply Obj.” source