The sense of sight, as being altogether material, cannot be raised up to immateriality.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic sight senses
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

“The angelic intellect is not defective, if defect be taken to mean privation, as if it were without anything which it ought to have. But if the defect be taken negatively, in that sense every creature is defective, when compared with God; forasmuch as it does not possess the excellence which is in God. Reply Obj. 3: The sense of sight, as being altogether material, cannot be raised up to immateriality. But our intellect, or the angelic intellect, inasmuch as it is elevated above matter in its own nature, can be raised up above its own nature to a higher level by grace. The proof is, that sight cannot in any way know abstractedly what it knows concretely;” source