The art of war is of vital importance to the State. It is a matter of life and death, a road either to safety or to ruin. It is governed by five constant factors namely the Moral Law, Heaven, Earth, the Commander, method and discipline, when seeking to determine the conditions obtaining in the field. Hiding order beneath the cloak of disorder is simply a question of subdivision; concealing courage under a show of timidity presupposes a fund of latent energy; masking strength with weakness is to be effected by tactical dispositions. The art of war teaches us to rely not on the likelihood of the enemy's not coming, but on our own readiness to receive him; not on the chance of his not attacking, but rather on the fact that we have made our position unassailable. Prohibit the taking of omens, and do away with superstitious doubts. Then, until death itself comes, no calamity need be feared.