If you know the enemy and know yourself, you need not fear the result of a hundred battles. If you know yourself but not the enemy, for every victory gained you will also suffer a defeat. If you know neither the enemy nor yourself, you will succumb in every battle.

The passage ties strategic readiness to knowledge. Someone who understands both opponent and self can face a hundred battles without fear; knowing only oneself means each win is matched by a loss; knowing neither means defeat every time. Self-knowledge alone is not enough without understanding the adversary.

Context reviewed 29 September 2026