Really every child is to a certain extent a genius, and the genius is to a certain extent a child.
 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 extent
Date 1819
Language English
Reference
Note Translated by R. B. Haldane and J. Kemp
Weblink http://www.gutenberg.org/files/40868/40868-h/40868-h.html

Context

“On what, then, the likeness between childhood and genius depends I scarcely need to express further: upon the surplus of the powers of knowledge over the needs of the will, and the predominance of the purely intellectual activity which springs from this. Really every child is to a certain extent a genius, and the genius is to a certain extent a child. The relationship of the two shows itself primarily in the naïveté and sublime simplicity which is characteristic of true genius; and besides this it appears in several traits, so that a certain childishness certainly belongs to the character of the genius.” source