badness is only spoiled goodness. And there must be something good first before it can be spoiled.
 C. S. Lewis, Mere Christianity (1952). copy citation

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Author C. S. Lewis
Source Mere Christianity
Topic goodness good
Date 1952
Language English
Reference
Note Adapted from a series of BBC radio talks made between 1942 and 1944
Weblink https://www.dacc.edu/assets/pdfs/PCM/merechristianitylewis.pdf

Context

“but no one ever did a cruel action simply because cruelty is wrong—only because cruelty was pleasant or useful to him. In other words badness cannot succeed even in being bad in the same way in which goodness is good. Goodness is, so to speak, itself: badness is only spoiled goodness. And there must be something good first before it can be spoiled. We called sadism a sexual perversion; but you must first have the idea of a normal sexuality before you can talk of its being perverted; and you can see which is the perversion, because you can explain the perverted from the normal, and cannot explain the normal from the perverted.” source