A man becomes another's slave not only by being overcome by him, but also by subjecting himself to him spontaneously
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic overcoming subject
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

“which desire might be inordinate, unless it were subordinate to reason, a matter that is subject to the free-will. Reply Obj. 1: The crowd of demons are the cause of all our evils, as regards their original cause, as stated. Reply Obj. 2: A man becomes another's slave not only by being overcome by him, but also by subjecting himself to him spontaneously: it is thus that one who sins of his own accord, becomes the slave of the devil. Reply Obj. 3: The devil's sin was irremediable, not only because he sinned without another's suggestion; but also because he was not already prone to sin, on account of any previous sin;” source