as man is something added to animal which can be understood if rational be taken away.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic understanding animal
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

“It would seem that the hypostases remain if the properties or relations are mentally abstracted from the persons. For that to which something is added, may be understood when the addition is taken away; as man is something added to animal which can be understood if rational be taken away. But person is something added to hypostasis; for person is "a hypostasis distinguished by a property of dignity." Therefore, if a personal property be taken away from a person, the hypostasis remains.” source