as by whiteness a thing is white, and by manhood a thing is man.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic manhood
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

“to the hypostasis as to that which has being—and to the nature as to that whereby it has being. For nature is taken after the manner of a form, which is said to be a being because something is by it; as by whiteness a thing is white, and by manhood a thing is man. Now it must be borne in mind that if there is a form or nature which does not pertain to the personal being of the subsisting hypostasis, this being is not said to belong to the person simply, but relatively;” source