Only those who intuitively know the nature of men as they are as a rule, and thus comprehend the individuality of the person before them, will understand how to manage him with certainty and rightly.
 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 individuality certainty
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

“In practical life the intuitive knowledge of the understanding is able to guide our action and behaviour directly, while the abstract knowledge of the reason can only do so by means of the memory. Hence arises the superiority of intuitive knowledge in all cases which admit of no time for reflection; thus for daily intercourse, in which, just on this account, women excel. Only those who intuitively know the nature of men as they are as a rule, and thus comprehend the individuality of the person before them, will understand how to manage him with certainty and rightly. Another may know by heart all the three hundred maxims of Gracian, but this will not save him from stupid mistakes and misconceptions if he lacks that intuitive knowledge. For all abstract knowledge affords us primarily mere general principles and rules;” source