In Chinese cosmology, the universe began with one fundamental element: qi(or chi), the vital energy that animates all things and governs matter, time, and space. In some myths, qi was contained in a huge egg until it separated into the dual, complementary elements of yin and yang. Yin represents the passive, female principle of the universe—cold, dark, and earthly. Yang represents the active, male principle of the universe—hot, bright, and heavenly. These forces continuously oppose and balance one another, distinct parts that are necessary for composite whole of the universe.
Within this yin and yang was Pan Gu, who broke forth from the egg as the giant who separated chaos into the many opposites, including Earth and sky. Pan Gu stood in the middle, his head touching the sky, his feet planted on Earth. The heavens and the Earth began to grow at a rate of 10 feet a day, and Pan Gu grew along with them. After another 18,000 years the sky was higher and Earth was thicker. Pan Gu stood between them like a pillar 30,000 miles in height, so they would never again join.
When Pan Gu died, his skull became the top of the sky, his breath became the wind and clouds, his voice the rolling thunder. One eye became the Sun and the other the Moon. His body and limbs turned into five big mountains, and his blood formed the roaring water. His veins became roads and his muscles turned to fertile land. The innumerable stars in the sky came from his hair and beard, and flowers and trees from his skin. His marrow turned to jade and pearls. His sweat flowed like the good rain and the sweet dew that nurtures all things on Earth. Some people say that the fleas and the lice on his body became the ancestors of humanity.
The Flood
Chinese mythology has a couple of flood stories. In one early account, a farmer managed to capture and imprison a thunder God. The farmer's children took pity on the thunder god and released him. In gratitude, the God warned them there was going to be a great flood and gave them a very large gourd to keep them safe from the waters (sounds like a James and the Giant Peach moment).
The brother and sister were the only people to survive the flood, making repopulating the earth a bit tricky. According to one version, the sister puts her brother through many seemingly impossible physical challenges before agreeing to marry him. He completed the tasks, they married, and she had a child. The child was born damaged, without arms and legs. The brother killed the baby by cutting it up and throwing the pieces over the hill. The next day the brother and sister found that the pieces had turned into men and women.
Another account of the Great Flood is said to have occurred during the reign of Emperor Yao. After the flooding began, he sought the advice of his advisors, the Four Mountains, who told him to appoint his distant cousin Gun to control the floods. Gun accepted the commission and chose to steal Xirang, a self-expanding soil, from the supreme deity. He continuously used this soil to build dams and embankments to battle the oncoming flood, but they would not hold and generally collapsed. Gun's son, Yu, spent much of his time studying why his efforts failed. Working with a semi-mythical agricultural master, Yu devised a successful system of flood control, including dams and irrigation canals. He spent much of his time assisting the common workers, even if it meant being away from his own family. His methods were successful, and Chinese culture flourished along the rivers. As his reward, Yu became emperor (Yu the Great).