There is no opponent. Because the word "I" does not exist.

A good fight should be like a small play, but played seriously. A good martial artist does not become tense, but ready. Not thinking, yet not dreaming. Ready for whatever may come. When the opponent expands, I contract. When he contracts, I expand. And when there is an opportunity, I do not hit. It hits all by itself.

— Bruce Lee, Enter the Dragon