Huang Tingjian has been troubled by things that he can't write with a pen and his pen is dull for many years, so he took a boat across the Three Gorges that night and saw the boatmen leaning forward and backward rhythmically in a certain space, pushing out the paddles to save them, and going back and forth, in harmony with nature. Huang Tingjian realized how to use a pen naturally by the boatman's action of rocking the paddle.