The knowledge of things by the senses is in proportion to the existence of their likeness in the senses
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic likeness existence
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

“, and this takes place through the senses apprehending things as they are, and hence it happens that falsity exists in the senses through their apprehending or judging things to be otherwise than they really are. The knowledge of things by the senses is in proportion to the existence of their likeness in the senses; and the likeness of a thing can exist in the senses in three ways. In the first way, primarily and of its own nature, as in sight there is the likeness of colors, and of other sensible objects proper to it.” source