“Pretend inferiority and encourage his arrogance”

This quote from Sun Tzu says that is better to make your enemy think you are inferior to him, to a degree that leads him to underestimate you and blunder. Regardless of arrogance level, it is usually beneficial o have greater ability than your enemy thinks you have.

If your enemy thinks you have a certain skill and aptitude level, he is unlikely to be prepared for your true level, and will thus not be able to react to what you do in as efficient way as if he had been expecting it.

But this goes beyond surprising your enemy with your actual ability. If the enemy views you so low that he disregards you, he is more likely to do things that leave him in a more vulnerable position. That is when you strike.

Take Chess as an example. Against most players of good ability, I wouldn’t try checkmate moves that they can obviously see and block, leaving my important pieces vulnerable.

But if I were going against someone who I knew (or thought) could not see these checkmate moves, I might try them, for a quick victory. If I did that against someone who happened to be a skilled chess player, it would immediately put me in a disadvantage, as they would read my moves, and quickly take or attack my important pieces.

This is why underestimation of, and arrogance toward, your opponents can lead to terrible outcomes. And why pretending inferiority and encouraging the enemy’s arrogance can lead to your victory.