Mightily miffed at not being invited to the wedding of Peleus and Thetis, Achilles's parents, the goddess Eris shows up anyway and throws a golden apple of discord among the guests. On the apple is written the legend "To the fairest."

Not surprisingly, all the goddesses present want to claim that exalted title for themselves, and Hera, Athena, and Aphrodite fight over the golden apple. As none of them is prepared to back down, some kind of contest will need to be held in order to determine who really is the fairest.

Zeus is not prepared to do this himself as it will cause him all kinds of bother. So instead, he heaps this onerous responsibility onto the shoulders of Paris, the Trojan prince. Paris has a reputation as a wise and fair judge, and so it's thought that he would be the ideal person to decide which goddess is the fairest.

In a bull-judging competition, he chose the god Ares disguised as a bull over his own prize animal as the former was clearly superior. It's this kind of fair-minded, impartial judgment that Zeus wants to see Paris use in deciding which goddess is the most beautiful.

In the event, Paris chooses Aphrodite after she offers him the bribe of the most beautiful woman in the world, Helen, the wife of the Spartan king Menelaus. In due course, Helen elopes with Paris, precipitating a long, drawn-out war between the Greeks and the Trojans.