Error can never be corrected by error, and evil cannot be vanquished by evil.
 Leo Tolstoy, The Kingdom of God Is Within You (1894). copy citation

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Author Leo Tolstoy
Source The Kingdom of God Is Within You
Topic evil error
Date 1894
Language English
Reference
Note Translated by Constance Garnett
Weblink http://www.gutenberg.org/cache/epub/4602/pg4602-images.html

Context

“To injure another because he has injured us, even with the aim of overcoming evil, is doubling the harm for him and for oneself; it is begetting, or at least setting free and inciting, that evil spirit which we should wish to drive out. Satan can never be driven out by Satan. Error can never be corrected by error, and evil cannot be vanquished by evil. True non-resistance is the only real resistance to evil. It is crushing the serpent's head. It destroys and in the end extirpates the evil feeling. Q. But if that is the true meaning of the rule of non-resistance, can it always put into practice?” source