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CHAPTER LXVI: AGAINST THOSE WHO SAY THAT INTELLECT AND SENSE ARE THE SAME
SOME of the early philosophers came near to these through thinking that intellect differs not from sense. But this is impossible.
For sense is found in all animals: whereas animals other than man have no intellect. This is evident from the fact that they do diverse and opposite things, not as though they had intelligence, but as moved by nature, performing certain determinate operations that are uniform within the same species: thus every swallow builds its nest in the same say. Therefore intellect is not the same as sense.
Further. Sense is not cognizant except of singulars: for every sensitive power knows by individual species, since it receives the species of things in corporeal organs. But the intellect is cognizant of universals, as evidenced by experience. Therefore intellect differs from sense.
Moreover. The knowledge of the senses does not extend beyond things corporeal. This is clear from the fact that sensible qualities, which are the proper objects of the senses, are only in corporeal things, and without them the senses know nothing. On the other hand the intellect knows things incorporeal, for instance, wisdom, truth, and the relations of things. Therefore intellect and sense are not the same.
Again. Sense knows neither itself nor its operation: for sight neither sees itself, nor sees that it sees, but this belongs to a higher power, as is proved in De Anima. But the intellect knows itself, and knows that it understands. Therefore intellect is not the same as sense.
Further. Sense is corrupted by an excelling sensible. But intellect is not corrupted by the excellence of the intelligible; in fact, he who understands greater things, can afterwards better understand lesser things. Therefore the sensitive power differs from the intellective.
|Source: St. Thomas Aquinas, The Summa Contra Gentiles, trans. by The English Dominican Fathers from the latest Leonine Edition, Benzinger Brothers: New York, 1924.|