Zen in the martial arts

is an excellent book by Joe Hyams (isbn 0-87477-101-3). As usual I'm going to quote from a few pages:
At least empty your cup and try.
Those who are patient in the trivial things in life and control themselves will one day have the same mastery in great and important things.
The martial artist develops through practice until it becomes mechanical and then spontaneous.
When you lose your temper, you lose yourself - on the mat as well as in life.
The proper system is to think twice more. Patience is part of it. To avoid being intimidated - think more and react less.
Try softer. When one eye is fixed upon your destination, there is only one eye left with which to find the way.
To know and to act are one and the same.
Relaxation and concentration go hand in hand. But too much concentration defeats itself.
Most of the time we generate our own fears, and this is especially true when we confront an unfamiliar situation that shatters confidence.
Years ago I thought too much about what I had to do, laboured over it, put off difficult chores, waited for the mood to be right or the creative juices to flow. Now I just do it without conscious effort. It flows because the work and I are one, and not in conflict with each other.
The only reason men fight is because they are insecure; one man needs to prove that he is better or stronger than another. The man who is secure within himself has no need to prove anything with force, so he can walk away from a fight with dignity and pride.