Mencius, Book 3, Part 1, Chapter 1.
1. When the duke Wan of T'ang was crown prince, having to go to Ts'oo, he went by way of Sung, and visited mencius.
2. Mencius discoursed to him how the nature of man is good, and, when speaking, always made laudatory reference toYaou and Shun.
3. When the crown prince was returning from Ts'oo, he again visited Mencius. Mencius said to him, "Prince, do you doubt my words? The path is one, and only one.
4. "Shing Kan said to the duke of Ts'e, 'They were men. I am a man. Why should I stand in awe of them? Yen Yuen said, 'What kind of man was Shun? What kind of man am I? He who exerts himself will also become such as he was.' Kung-ming E said, 'King Wan is my teacher. How should the duke of Chow deceive me by those words?'
5. "Now, T'ang, taking its length with its breadth, will amount, I suppose, to fifty li. It is small, but still sufficient to make a good kingdom. It is said in the 'Book of History,' 'If medicine do not raise a commotion in the patient, his disease willnot be cured by it.' "
Text source: The Works of Mencius. Translated by James Legge.