1
Sun Tzu said: The good fighters of old first put themselves beyond the possibility of defeat, and then waited for an opportunity of defeating the enemy.
2
To secure ourselves against defeat lies in our own hands, but the opportunity of defeating the enemy is provided by the enemy himself.
3
Thus the good fighter is able to secure himself against defeat,
but cannot make certain of defeating the enemy.
4
Hence the saying: One may KNOW how to conquer without being able to DO it.
5
Security against defeat implies defensive tactics; ability to defeat the enemy means taking the offensive.