故經之以五事,校之以計,而索其情,一曰道,二曰天,三曰地,四曰將,五曰法。
The art of war, then, is governed by five constant factors, to be taken into account in one's deliberations, when seeking to determine the conditions obtaining in the field. These are: (1) The Moral Law; (2) Heaven; (3) Earth; (4) The Commander; (5) Method and discipline.