The Art of War
tr. by Lionel Giles (1910)
If you know neither the enemy nor yourself, you will succumb in every battle.–p. 25, II:18.
Anger may in time change to gladness;
Vexation may be succeeded by content.
But a kingdom that has once been destroyed
Can never come again into being;
Nor can the dead ever be brought back to life.
Hence the enlightened ruler is heedful,
And the good general full of caution.
This is the way to keep a country at peace and an army intact.
–p. 159, XII:20-22.