Mencius - Book 3, Part 2, Chapter 9B

'After the death of Yâo and Shun, the principles that mark sages fell into decay. Oppressive sovereigns arose one after another, who pulled down houses to make ponds and lakes, so that the people knew not where they could rest in quiet; they threw fields out of cultivation to form gardens and parks, so that the people could not get clothes and food. Afterwards, corrupt speakings and oppressive deeds became more rife; gardens and parks, ponds and lakes, thickets and marshes became more numerous, and birds and beasts swarmed. By the time of the tyrant Châu, the kingdom was again in a state of great confusion.

'Châu-kung assisted king Wû, and destroyed Châu. He smote Yen, and after three years put its sovereign to death. He drove Fei-lien to a corner by the sea, and slew him. The States which he extinguished amounted to fifty. He drove far away also the tigers, leopards, rhinoceroses, and elephants; and all the people was greatly delighted. It is said in the Book of History, "Great and splendid were the plans of king Wan! Greatly were they carried out by the energy of king Wû! They are for the assistance and instruction of us who are of an after day. They are all in principle correct, and deficient in nothing."

'Again the world fell into decay, and principles faded away. Perverse speakings and oppressive deeds waxed rife again. There were instances of ministers who murdered their sovereigns, and of sons who murdered their fathers.

'Confucius was afraid, and made the "Spring and Autumn." What the "Spring and Autumn" contains are matters proper to the sovereign. On this account Confucius said, "Yes! It is the Spring and Autumn which will make men know me, and it is the Spring and Autumn which will make men condemn me."
~ James Legge translation via nothingistic.org ~

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