whoever will breed a boy to be good for anything when he comes to be a man, must by no means spare him when young, and must very often transgress the rules of physic
 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 meaning rules
Date 1580
Language English
Reference
Note Translated by Charles Cotton
Weblink http://www.gutenberg.org/files/3600/3600-h/3600-h.htm

Context

“They will not endure to see them return all dust and sweat from their exercise, to drink cold drink when they are hot, nor see them mount an unruly horse, nor take a foil in hand against a rude fencer, or so much as to discharge a carbine. And yet there is no remedy; whoever will breed a boy to be good for anything when he comes to be a man, must by no means spare him when young, and must very often transgress the rules of physic: “Vitamque sub dio, et trepidis agat In rebus.” [“Let him live in open air, and ever in movement about something.” —Horace, Od. ii., 3, 5.] It is not enough to fortify his soul; you are also to make his sinews strong;” source