Emotion can be the enemy, if you give into your emotion, you lose yourself. You must be at one with your emotion, because the body always follows the mind.
Low aim, not failure, is the crime.
Simplicity of expression rather than complexity of form.
A good fighter must sense rather than perceive his chance to strike.
A good martial artist does not become tend but ready, not thinking but jet not dreaming. Ready for whatever may come.
The martial arts are ultimately self-knowledge. A punch or a kick is not to knock the hell out of the guy in front, but to knock the hell out of your ego, your fear, or your hang-ups.