For we know man vaguely as man before we know how to distinguish all that belongs to human nature.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic human nature
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

“For we know a house vaguely before we know its different parts. So likewise principles of definition are known before the thing defined is known; otherwise the thing defined would not be known at all. But as parts of the definition they are known after. For we know man vaguely as man before we know how to distinguish all that belongs to human nature. Reply Obj. 4: The universal, as understood with the intention of universality, is, indeed, in a way, a principle of knowledge, in so far as the intention of universality results from the mode of understanding by way of abstraction.” source