Chinese idiom：朝三暮四
朝三暮四 
Zhao(1)San(1)Mu(4)Si(4)
Three in the morning, four in the evening — Play fast and loose
In the Warring States Period (475-221BC), there was an old man who had a barrel of monkeys. They spent so much time together that the old man was able to communicate back and forth with the monkeys and they often had a whole bunch of fun. Every day, the old man liked to feed them a little treat: Chestnuts. But after a few years, he realized he had to cut back on the luxuries.
"From now on, I'll give each of you three chestnuts in the morning and four in the evening. What do you say to that?" The monkeys replied they didn't like that at all, no sir, and angrily bashed their hands against the walls.
Easy now, easy!" said the old man. "Alright. Instead I'll give you four chestnuts for breakfast and three for supper. How about that?" he said. The monkeys immediately calmed down as this sounded like a much better proposal...to an unthinking ape.
In the past, this idiom meant there's one sucker born every minute. But nowadays it's used to describe someone who doesn't know his mind and vacillates back and forth.
Chinese idiom：朝三暮四