Lieh Tzŭ had Lao Shang for his teacher, and Po Kao Tzŭ for his friend. When he had fully mastered the system of these two philosophers, he rode home again on the wings of the wind. Yin Shêng heard of this, and became his disciple. He dwelt with Lieh Tzŭ for many months without visiting his own home. While he was with him, he begged to be initiated into his secret arts. Ten times he asked, and each time received no answer. Becoming impatient Yin Shêng announced his departure, but Lieh Tzŭ still gave no sign. So Yin Shêng went away, but after many months his mind was still unsettled, so he returned and became his follower once more. Lieh Tzŭ said to him: 'Why this incessant going and coming?' Yin Shêng replied: 'Some time ago, I sought instruction from you, Sir, but you would not tell me anything. That made me vexed with you. But now I have got rid of that feeling, and so I have come again.' Lieh Tzŭ said: 'Formerly, I used to think you were a man of penetration, and have you now fallen so low? Sit down, and I will tell you what I learned from my Master. After I had served him, and enjoyed the friendship of Po Kao, for the space of three years, my mind did not venture to reflect on right and my wrong, my lips did not venture to speak of profit and loss. Then, for the first time, my Master bestowed one glance upon me — and that was all. 'At the end of five years a change had taken place; my mind was reflecting on right and wrong, and my lips were speaking of profit and loss. Then, for the first time, my Master relaxed his countenance and smiled. 'At the end of seven years, there was another change. I let my mind reflect on what it would, but it no longer occupied itself with right and wrong. I let my lips utter whatsoever they pleased, but they no longer spoke of profit and loss. Then, at last, my Master led me in to sit on the mat beside him. 'At the end of nine years my mind gave free rein to its reflections, my mouth free passage to its speech. Of right and wrong, profit and loss, I had no knowledge, either as touching myself or others. I knew neither that the Master was my instructor, nor that the other man was my friend. Internal and External were blended into Unity. After that, there was no distinction between eye and ear, ear and nose, nose and mouth: all were the same. My mind was frozen, my body in dissolution, my flesh and bones all melted together. I was wholly unconscious of what my body was resting on, or what was under my feet. I was borne this way and that on the wind, like dry chaff or leaves falling from a tree. In fact, I knew not whether the wind was riding on me or I on the wind. Now, you have not spent one whole season in your teacher's house, and yet you have lost patience two or three times already. Why, at this rate, the atmosphere will never support an atom of your body, and even the earth will be unequal to the weight of one of your limbs! How can you expect to walk in the void or to be charioted on the wind?' Hearing this, Yin Shêng was deeply ashamed. He could hardly trust himself to breathe, and it was long ere he ventured to utter another word.