Dr. Cliff Post, the Egyptologist believes in The Ancient Aliens Theory. His friend Dr. Kyle Wilson, the marine archeologist believes in the cyclical theory of history.
In the cyclical theory of history, a civilization achieves many advanced technologies and a vast body of scientific knowledge.
That advanced civilization is destroyed either through war or a natural disaster such as volcanoes, earthquakes or a massive flood.
The survivors lose their technologies and their knowledge.
They start over again on a primitive level.
A good example of this phenomenon is the Fall of the Roman Empire which plunged Europe into the Dark Ages.
Then a rebirth occurred in which the sciences and technologies were rediscovered during the Renaissance.
In ancient times, the Alexandria Library in Alexandria, Egypt was destroyed.
The Alexandria Library was said to be a vast repository of ancient knowledge.
Evidence has come to light that the ancient Egyptians have a very advanced knowledge of mathematics and astronomy.
In addition, even with our modern technologies we would be hard pressed to replicate the engineering feats of the ancient Egyptians.
For example, the face of Ramses II was so precisely carved that if it is photographed and placed in a computer program the left side of Ramses is proven to be the exact mirror image of the right side of Ramses face.
In conclusion, the cyclical theory of history shows that throughout history knowledge has been lost and regained repeatedly.