The likeness of a thing known is not of necessity actually in the nature of the knower
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic likeness necessity
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

“There is, again, another mover, which is moved essentially—namely, the body. And because the philosophers of old believed that nothing existed but bodies, they maintained that every mover is moved; and that the soul is moved directly, and is a body. Reply Obj. 2: The likeness of a thing known is not of necessity actually in the nature of the knower; but given a thing which knows potentially, and afterwards knows actually, the likeness of the thing known must be in the nature of the knower, not actually, but only potentially; thus color is not actually in the pupil of the eye, but only potentially.” source