Chapter 31
夫佳兵者，不祥之器，物或惡之，故有道者不處。
君子居則貴左，用兵則貴右。
兵者不祥之器，非君子之器，不得已而用之，恬淡為上。
勝而不美，而美之者，是樂殺人。
夫樂殺人者，則不可得志於天下矣。
吉事尚左，凶事尚右。
偏將軍居左，上將軍居右，言以喪禮處之。
殺人之眾，以悲哀泣之，戰勝以喪禮處之。
Fine weapons are tools of ill omen; creatures loathe them, and so one who has the Way does not abide with them.
The gentleman at home honors the left; in war he honors the right.1
Weapons are tools of ill omen, not the tools of a gentleman; when he has no choice but to use them, calm detachment is best.
He wins but does not think it fine; to think it fine is to delight in killing people.
One who delights in killing people cannot have his way in the world.
In happy affairs the left is honored; in grievous affairs, the right.
The lieutenant general stands on the left, the commanding general on the right: that is to say, they are placed as at a funeral.
When multitudes have been killed, weep for them in grief and sorrow; when a battle is won, observe it with the rites of mourning.
Notes
1. In the old rites the left was the place of life and happy occasions, the right the place of death and mourning.