A cow cannot be very good or very bad; a dog can be both better and worse; a child better and worse still; an ordinary man, still more so; a man of genius, still more so
 C. S. Lewis, Mere Christianity (1952). copy citation

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Author C. S. Lewis
Source Mere Christianity
Topic genius cow
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

“‘Why did God make a creature of such rotten stuff that it went wrong?’ The better stuff a creature is made of—the cleverer and stronger and freer it is—then the better it will be if it goes right, but also the worse it will be if it goes wrong. A cow cannot be very good or very bad; a dog can be both better and worse; a child better and worse still; an ordinary man, still more so; a man of genius, still more so; a superhuman spirit best—or worst—of all. How did the Dark Power go wrong? Here, no doubt, we ask a question to which human beings cannot give an answer with any certainty. A reasonable (and traditional)” source