It's almost certainly some paraphrasing of Sun Tzu.

Hence to fight and conquer in all your battles is not supreme excellence; supreme excellence consists in breaking the enemy’s resistance without fighting.

For to win one hundred victories in one hundred battles is not the acme of skill. To subdue the enemy without fighting is the acme of skill.

Copying Sun Tzu's homework is a pretty common way to write wise leader characters. You've probably seen a dozen variations on this.