No wise man is the cause of another man becoming worse.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic cause
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

“But God does not will that evil should not exist; otherwise, since various evils do exist, God's will would not always be fulfilled. Therefore God wills that evil should exist. On the contrary, Augustine says (Qq. 83,3) : "No wise man is the cause of another man becoming worse. Now God surpasses all men in wisdom. Much less therefore is God the cause of man becoming worse; and when He is said to be the cause of a thing, He is said to will it." Therefore it is not by God's will that man becomes worse.” source