Dr brewer recounts the story of Ancaeus, the helmsman of Jason’s ship Argo in Greek mythology. ‘He was told by a slave that he would never live to taste the wine of his vineyards. When a bottle made from his own grapes was set before him, he sent for the slave to laugh at his prognostications; but the slave made answer, “There’s many a slip ‘twixt the cup and the lip.” At this instant a messenger came in, and told Ancaeus that the Calydonian boar was laying his vineyard waste, whereupon he set down his cup, went out against the boar, and was killed in the encounter.’
Hence nothing is certain until you possess it.