In estimating the number of men of outstanding genius, we must of course only count those who have produced works which have retained through all time an enduring value for mankind.
 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 genius value
Date 1819
Language English
Reference
Note Translated by R. B. Haldane and J. Kemp
Weblink http://www.gutenberg.org/files/38427/38427-h/38427-h.html

Context

“number of really great men of genius that the whole of civilised Europe has produced, both in ancient and modern times, with the two hundred and fifty millions who are always living in Europe, and who change entirely every thirty years. In estimating the number of men of outstanding genius, we must of course only count those who have produced works which have retained through all time an enduring value for mankind. I shall not refrain from mentioning, that I have known some persons of decided, though not remarkable, mental superiority, who also showed a slight trace of insanity. It might seem from this that every advance of intellect beyond the ordinary measure, as an abnormal development, disposes to madness.” source