Long ago, there were three sexes: male, female, and a union of the two. Each person was built like a ball, with two faces looking opposite directions. Though fast and strong, originally humans were neither agile nor bold. Like antelope, they would roam in herds, and lived happily and complacently where food was plentiful.
The gods were displeased, because humans spent no time worshiping them, made no fine arts, and any god-child unfortunate enough to be raised amongst them would grow up utterly bereft of noble desires. They considered annihilating the whole race, as they had the giants.
After long reflect, Zeus said, "I think I have a plan to give them ambition. I shall give them a twist, and turn one face around, so that it can only stare inside. Like a bubble of air in dough, I'll place a bit of nothingness in the center of each one, and turn that inner face to look at it. It will be the same nothingness of which we ourselves are made." And it was done.
The new humans became anguished and miserable, because they feared the pocket of divine nothingness in their hearts. They devoted themselves to material possessions or gluttony to try to fill their void. Zeus saw that they were dying and took pity on them. He turned their generative organs to the front, for this was not always their position, so humans now sewed their seed not like grasshoppers in the ground, but in one another.
The other gods objected. "They will think only of joining together to try to regain a false semblance of their original form, and when they cannot they will be despondent," Apollo cried. So Zeus bestowed one final gift. He gave each person a special compass, which would point them in the direction of the next few steps on the twisty trail to happiness. Sometimes it would point toward other people, sometimes to other places, sometimes to contemplation, and sometimes to creation.