Attack by Stratagem:

Thus we may know that there are five essentials for Victory:

(1) He will win who knows when to fight and when not to fight.
(2) He will win who knows how to handle both superior and inferior forces.
(3) He will win who's army is animated by the same spirit throughout all its ranks.
(4) He will win who, prepared himself, waits to take the enemy unprepared.
(5) He will win who has military capacity and is not interfered with by the sovereign

Victory lies in the knowledge of these five points.

Hence the saying: If you know the enemy and know yourself, you need not fear the result of a
hundred battles. if you know yourself and not the enemy, for every victory gained you will also
suffer a defeat. If you know nether the enemy nor yourself you will succumb in every battle.