, a person is an individual substance of rational nature.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/19950/pg19950-images.html

Context

“29, A. 3, ad 2) . Hence, since our human nature has its proper personality, much more reason was there that Christ's should have its proper personality. Obj. 3: Further, as Boethius says (De Duab. Nat.) , a person is an individual substance of rational nature. But the Word of God assumed an individual human nature, for "universal human nature does not exist of itself, but is the object of pure thought," as Damascene says (De Fide Orth. iii, 11) . Therefore the human nature of Christ has its personality.” source