Any man will be able, after sufficient practice, to accomplish remarkable feats of strength, but he may go only so far and no farther. There is a limit to human physical strength that no one can exceed.
Gichin FunakoshiYou must be deadly serious in training. When I say that, I do not mean that you should be reasonably diligent or moderately in earnest. I mean that your opponent must always be present in your mind, whether you sit or stand or walk or raise your arms.
Gichin FunakoshiStudents of any art, including Karate-do must never forget the cultivation of the mind and the body.
Gichin Funakoshi