What man knoweth the things of a man, but the spirit of a man that is in him?
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic spirit
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

“Our mental concept is hidden by a twofold obstacle. The first is in the will, which can retain the mental concept within, or can direct it externally. In this way God alone can see the mind of another, according to 1 Cor. 2:11: "What man knoweth the things of a man, but the spirit of a man that is in him?" The other obstacle whereby the mental concept is excluded from another one's knowledge, comes from the body; and so it happens that even when the will directs the concept of the mind to make itself known, it is not at once make known to another;” source