以人为鉴

Explanation: Refers to the success or failure of others as their own warning. 　　Source: "Wine Patent book" The ancients have Yanyue 'No one in the water prison, when the people monitoring. '"In order; supervisor, Mirror", mirrors. "Mandarin Wu" He has given his people the king, no view of the water. "Wei Zhao note cited" book, "Kam said, No one in the water, when the people Kam." 　　Examples: With copper as a mirror, can be positive or dressed; to the ancient as a mirror, we can see the rise and fall, ~, can be advantages and disadvantages. ★ "New Book of Tang Wei Zheng Biography" Thesaurus:  To people as a mirror