Copyright: the fox and the grapes
The Fox and the Grapes is one of Aesop's Fables.
The fable is about a fox who notices a bunch of grapes that are out of his reach. He makes several attempts to get them (to no avail) before giving up on them, concluding the grapes must be sour (i.e. not yet ripe).
The fable is where the expression "sour grapes" comes from.
This tag implicates aesop's_fables (learn more).