If, however, by man's fruit we understand a product of man, then human actions are called fruits: because operation is the second act of the operator, and gives pleasure if it is suitable to him.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic action understanding
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/17897/pg17897-images.html

Context

“For a man has both a field and a tree, and yet these are not called fruits; but that only which is last, to wit, that which man intends to derive from the field and from the tree. In this sense man's fruit is his last end which is intended for his enjoyment.
If, however, by man's fruit we understand a product of man, then human actions are called fruits: because operation is the second act of the operator, and gives pleasure if it is suitable to him. If then man's operation proceeds from man in virtue of his reason, it is said to be the fruit of his reason: but if it proceeds from him in respect of a higher power, which is the power of the Holy Ghost, then man's operation is said to be the fruit of the Holy Ghost, as of a Divine seed, for it is written (1 John 3:9) : "Whosoever is born of God, committeth no sin, for His seed abideth in him."
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