When a man says about something he wants to do, ‘It can’t be wrong because it doesn’t do anyone else any harm,’ he is thinking only of the first thing.
 C. S. Lewis, Mere Christianity (1952). copy citation

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Author C. S. Lewis
Source Mere Christianity
Topic wrong harm
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

“When people say in the newspapers that we are striving for Christian moral standards, they usually mean that we are striving for kindness and fair play between nations, and classes, and individuals; that is, they are thinking only of the first thing. When a man says about something he wants to do, ‘It can’t be wrong because it doesn’t do anyone else any harm,’ he is thinking only of the first thing. He is thinking it does not matter what his ship is like inside provided that he does not run into the next ship. And it is quite natural, when we start thinking about morality, to begin with the first thing, with social relations.” source