"Sour-grape" vs "The grass is greener on the other side"

• "The grass is always greener on the other side" suggests that people spend much of their time longing for things they don't have.
• In Aesop's fable of "The Fox and the Grapes", the fox walked away from the grapes he desired because he could not reach it, concluding that the grapes were probably sour anyway. This tale teaches that failure can make future success appear less attractive.

In a study, people who see grass as greener on the other side predict higher happiness with future success. Participants that reacted like Aesop's fox would try to distance themselves from failure. It suggests that initial failure made people underestimate how good it would feel to succeed.