Who said "When capable, appear incapable. When active, inert."?

This quote is attributed to Sun Tzu.

When capable, appear incapable. When active, inert. - Sun Tzu

"When capable, appear incapable. When active, inert."

Sun Tzu

Military Strategist Chinese 544–496

"All warfare is based on deception."

"Know your enemy and know yourself."

"If you know the enemy and know yourself, you need not fear the result of a hundred battles."

"The supreme art of war is to subdue the enemy without fighting."