Man no longer follows instinct with the old natural fidelity. He has developed into a reasoning creature, and can intellectually cling to life or discard life just as life happens to promise great pleasure or pain.
 Jack London, The People of the Abyss (1903). copy citation

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Author Jack London
Source The People of the Abyss
Topic pain fidelity
Date 1903
Language English
Reference
Note
Weblink https://en.wikisource.org/wiki/The_People_of_the_Abyss

Context

“I, for one, from what I know of canals and workhouses, should choose the canal, were I in a similar position. And I make bold to contend that I am no more insane than Ellen Hughes Hunt, her husband, and the rest of the human herd. Man no longer follows instinct with the old natural fidelity. He has developed into a reasoning creature, and can intellectually cling to life or discard life just as life happens to promise great pleasure or pain. I dare to assert that Ellen Hughes Hunt, defrauded and bilked of all the joys of life which fifty-two years' service in the world had earned, with nothing but the horrors of the workhouse before her, was very rational and level-headed when she elected to jump into the canal.” source