The madman is not the man who has lost his reason. The madman is the man who has lost everything except his reason.
 G. K. Chesterton, Orthodoxy (1908). copy citation

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Author G. K. Chesterton
Source Orthodoxy
Topic reason
Date 1908
Language English
Reference
Note
Weblink http://www.gutenberg.org/cache/epub/130/pg130-images.html

Context

“He is not hampered by a sense of humour or by charity, or by the dumb certainties of experience. He is the more logical for losing certain sane affections. Indeed, the common phrase for insanity is in this respect a misleading one. The madman is not the man who has lost his reason. The madman is the man who has lost everything except his reason. The madman's explanation of a thing is always complete, and often in a purely rational sense satisfactory. Or, to speak more strictly, the insane explanation, if not conclusive, is at least unanswerable;” source