In the days of primitive man, they didn't understand that the Sun went around the Earth.

Caveman Zog always saw the sun go down before retiring for the night. But when he woke up the next morning and stepped out of his cave, ready to greet the day, he noticed that the sun was always up in the sky and on the opposite side from where it went down.

Zog was a smart and curious caveman so he decided to figure out how it worked. One night, he camped outside the cave and forced himself to stay awake all night. Hours went by in the dark while he pondered how the sun worked... and then all of a sudden it dawned on him!