Allaying Hunger with Pictures of Cakes

In the Three Kingdoms Period (220-280), the king of the Wei, Cao Rui, wanted to select a very capable man to work for him. He said to his ministers: 'When choosing a talented person, always beware of one with a false reputation. A false reputation is just like a picture of a cake; it can' t relieve hunger.' 

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Later, this idiom came to be used to mean comforting oneself with unrealistic thoughts, without solving practical problems.

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