War is not courtesy but the most horrible thing in life; and we ought to understand that and not play at war. We ought to accept this terrible necessity sternly and seriously. It all lies in that: get rid of falsehood and let war be war and not a game.
 Leo Tolstoy, War and Peace (1869). copy citation

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Author Leo Tolstoy
Source War and Peace
Topic courtesy falsehood
Date 1869
Language English
Reference
Note Translated by Louise and Aylmer Maude
Weblink http://www.gutenberg.org/files/2600/2600-h/2600-h.htm

Context

“And then the determination of the troops would be quite different. Then all these Westphalians and Hessians whom Napoleon is leading would not follow him into Russia, and we should not go to fight in Austria and Prussia without knowing why. War is not courtesy but the most horrible thing in life; and we ought to understand that and not play at war. We ought to accept this terrible necessity sternly and seriously. It all lies in that: get rid of falsehood and let war be war and not a game. As it is now, war is the favorite pastime of the idle and frivolous. The military calling is the most highly honored.
“ But what is war? What is needed for success in warfare? What are the habits of the military?” source