The understanding of the stupidest man becomes keen when objects are in question that closely concern his wishes
 Arthur Schopenhauer, The World as Will and Representation (1819). copy citation

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Author Arthur Schopenhauer
Source The World as Will and Representation
Topic question concern
Date 1819
Language English
Reference
Note Translated by R. B. Haldane and J. Kemp
Weblink http://www.gutenberg.org/files/40097/40097-h/40097-h.html

Context

“Difficult circumstances, which impose upon us the necessity of certain achievements, develop entirely new talents in us, the germs of which were hidden from us, and for which we did not credit ourselves with any [pg 437] capacity. The understanding of the stupidest man becomes keen when objects are in question that closely concern his wishes; he now observes, weighs, and distinguishes with the greatest delicacy even the smallest circumstances that have reference to his wishes or fears. This has much to do with the cunning of half-witted persons, which is often remarked with surprise.” source