Usually when someone wants to study something, they should first clearly understand its principle. Stand upright from the bottom of your feet, set your eyes with a steady gaze, grasp with a firm hand, and if you haven’t gone to the utmost, don’t stop. If you have this kind of determination, you can grasp this one thing. Even if you never make it to the summit, don’t stop half way down the road, or else how can you be called a serious person?
Le Yu Tang. Attributed to Huang Yuanji.