The mind is naturally free, not a slave; only what it does willingly, of its own accord, succeeds.
 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 mind
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

“And upon this also depends the fact that the former always speak only of what they have read, while the latter, on the contrary, speaks of what he has thought, and that they are, as Pope says: “For ever reading, never to be read.” The mind is naturally free, not a slave; only what it does willingly, of its own accord, succeeds. On the other hand, the compulsory exertion of a mind in studies for which it is not qualified, or when it has become tired, or in general too continuously and invita Minerva, dulls the brain, just as reading by moonlight dulls the eyes.” source