Mencius - Book 5, Part 1, Chapter 6C

'When the kingdom is possessed by natural succession, the sovereign who is displaced by Heaven must be like Chieh or Châu. It was on this account that Yî, Î Yin, and Châu-kung did not obtain the throne.

'Î Yin assisted T'ang so that he became sovereign over the kingdom. After the demise of T'ang, T'âi-ting having died before he could be appointed sovereign, Wâ'i-ping reigned two years, and Chung-zin four. T'âi-chiâ was then turning upside down the statutes of T'ang, when Î Yin placed him in T'ung for three years. There T'âi-chiâ repented of his errors, was contrite, and reformed himself. In T'ung be came to dwell in benevolence and walk in righteousness, during those three years, listening to the lessons given to him by Î Yin. Then Î Yin again returned with him to Po.

'Châu-kung not getting the throne was like the case of Yî and the throne of Hsiâ, or like that of Î Yin and the throne of Yin.

'Confucius said, "T'ang and Yü resigned the throne to their worthy ministers. The sovereign of Hsiâ and those of Yin and Châu transmitted it to their sons. The principle of righteousness was the same in all the cases."'
~ James Legge translation via nothingistic.org ~

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