A man who thinks himself a chicken is to himself as ordinary as a chicken. A man who thinks he is a bit of glass is to himself as dull as a bit of glass.
 G. K. Chesterton, Orthodoxy (1908). copy citation

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

Context

“but it requires two eyes to see the picture. And similarly even the wildest poetry of insanity can only be enjoyed by the sane. To the insane man his insanity is quite prosaic, because it is quite true. A man who thinks himself a chicken is to himself as ordinary as a chicken. A man who thinks he is a bit of glass is to himself as dull as a bit of glass. It is the homogeneity of his mind which makes him dull, and which makes him mad. It is only because we see the irony of his idea that we think him even amusing; it is only because he does not see the irony of his idea that he is put in Hanwell at all.” source