For knowledge always comes to things from without, and therefore must for ever remain outside them.
 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 self-knowledge
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

“From this whole inquiry it follows with certainty and distinctness that it is absolutely impossible to attain to the comprehension of the inner nature of things upon the path of mere knowledge and perception. For knowledge always comes to things from without, and therefore must for ever remain outside them. This end would only be reached if we could find ourselves in the inside of things, so that their inner nature would be known to us directly. Now, how far this is actually the case is considered in my second book.” source