War is a vital matter of state.
It is the field on which life or death is determined and the road that leads to either survival or ruin, and must be examined with the greatest care. The Art of War represents the earliest existing codification of military and political strategy, and is probably the most widely-read work on strategy in history. Sun Tzu's book is widely studied by the business and military communities today. During this period, the ruling Chou Dynasty gradually collapsed, and power drifted into the hands of increasingly independent provincial nobles. The tone of the text, which may easily be read as an exercise in Taoist philosophy, is profoundly influenced by both the increasing violence of the end of the Spring and Autumn period and by changes in the prevailing military technology.