but men, so soon as ever they are grownup, applying themselves to certain habits, engaging themselves in certain opinions, and conforming themselves to particular laws and customs, easily alter, or at least disguise, their true and real disposition; and yet it is hard to force the propension of nature.
 Michel de Montaigne, The Essays of Michel de Montaigne (1580). copy citation

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Author Michel de Montaigne
Source The Essays of Michel de Montaigne
Topic custom opinion
Date 1580
Language English
Reference
Note Translated by Charles Cotton
Weblink http://www.gutenberg.org/files/3600/3600-h/3600-h.htm

Context

“The symptoms of their inclinations in that tender age are so obscure, and the promises so uncertain and fallacious, that it is very hard to establish any solid judgment or conjecture upon them. Look at Cimon, for example, and Themistocles, and a thousand others, who very much deceived the expectation men had of them. Cubs of bears and puppies readily discover their natural inclination; but men, so soon as ever they are grownup, applying themselves to certain habits, engaging themselves in certain opinions, and conforming themselves to particular laws and customs, easily alter, or at least disguise, their true and real disposition; and yet it is hard to force the propension of nature. Whence it comes to pass, that for not having chosen the right course, we often take very great pains, and consume a good part of our time in training up children to things, for which, by their natural constitution, they are totally unfit.” source