Mencius - Book 4, Part 1, Chapter 20

Mencius said, 'It is not enough to remonstrate with a sovereign on account of the mal-employment of ministers, nor to blame errors of government. It is only the great man who can rectify what is wrong in the sovereign's mind. Let the prince be benevolent, and all his acts will be benevolent. Let the prince be righteous, and all his acts will be righteous. Let the prince be correct, and everything will be correct. Once rectify the ruler, and the kingdom will be firmly settled.'
~ James Legge translation via nothingistic.org ~

Go here to read the introductory post to this serialized version of the Works of Mencius.