Any pain through which a man can live at all becomes unfelt as soon as it becomes habitual. Pain consists not in that which is now endured but in the strong memory of something better that is still recent.
 Samuel Butler, The Note-Books of Samuel Butler (1912). copy citation

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Author Samuel Butler
Source The Note-Books of Samuel Butler
Topic pain memory
Date 1912
Language English
Reference
Note
Weblink http://www.gutenberg.org/files/6173/6173-h/6173-h.htm

Context

“Does it not seem as though he too must have committed some crime for which his sentence is to be for ever grasping after that which becomes non-existent the moment he grasps it? But then I suppose it would be with him as with the rest of the tortured, he must either die himself, which he has not done, or become used to it and enjoy the frightening as much as the killing. Any pain through which a man can live at all becomes unfelt as soon as it becomes habitual. Pain consists not in that which is now endured but in the strong memory of something better that is still recent. And so, happiness lies in the memory of a recent worse and the expectation of a better that is to come soon.
Ignorance of Death i
The fear of death is instinctive because in so many past generations we have feared it.” source