We believe that a man who, at thirty, has not the qualities of a general, will never have them; that he, whose glance cannot take in at once a tract of several leagues as if from every point of view, who is not possessed of that presence of mind which in victory leaves no advantage unimproved, and in defeat employs every resource, will never acquire such capacity.
 Montesquieu, Persian Letters (1721). copy citation

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Author Montesquieu
Source Persian Letters
Topic defeat victory
Date 1721
Language English
Reference
Note Translated by John Davidson
Weblink https://en.wikisource.org/wiki/Persian_Letters

Context

““never to advance officers whose patience has been worn out as subalterns; we look upon them as men whose minds have been narrowed by detail; and who, through a constant application to small things, are become incapable of great ones. We believe that a man who, at thirty, has not the qualities of a general, will never have them; that he, whose glance cannot take in at once a tract of several leagues as if from every point of view, who is not possessed of that presence of mind which in victory leaves no advantage unimproved, and in defeat employs every resource, will never acquire such capacity. Therefore we employ in brilliant services those great, those sublime men, on whom Heaven has bestowed not only the courage, but the genius of the hero; and in inferior services those whose talents are inferior.” source