For good natural parts are impaired by sloth; while inferior ability is3 mended by training: and while simple things escape the eyes of the careless, difficult things are reached by painstaking.
 Plutarch, Moralia (c. 100 AD). copy citation

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Author Plutarch
Source Moralia
Topic training escape
Date c. 100 AD
Language English
Reference
Note Translated by Arthur Richard Shilleto
Weblink http://www.gutenberg.org/files/23639/23639-h/23639-h.htm

Context

“But if anyone thinks that those who have not good natural ability cannot to some extent make up for the deficiencies of nature by right training and practice, let such a one know that he is very wide of the mark, if not out of it altogether. For good natural parts are impaired by sloth; while inferior ability is3 mended by training: and while simple things escape the eyes of the careless, difficult things are reached by painstaking. The wonderful efficacy and power of long and continuous labour you may see indeed every day in the world around you. 6 Thus water continually dropping wears away rocks: and iron and steel are moulded by the hands of the artificer: and chariot wheels bent by some strain can never recover their original symmetry: and the crooked staves of actors can never be made straight.” source