I always thought that we human beings are pinnacle of Humanity but I feel this thinking is not correct. There has been a civilizations prior to Sumerians that were far more advanced than we human beings.
So who was it ?
Atlanteans : http://en.wikipedia.org/wiki/Atlantis
Edgar Cayce was an extra ordinary human being, he made 14000 prediction out of which 12000 are already true. He was the one who predicted earth will be shifting poles in future. Edgar Cayce also talked about lost civilization of Atlantis (after Plato).
One of the most remarkable predictions from Edgar Cayce was about Hall of Records located underneath Sphinx. These records are last writings from Atlanteans. There is lot of information available on web and books written from Edgar Cayce for his predictions. Check this out : http://listverse.com/2012/01/06/top-10-predictions-from-edgar-cayce/
The level of technology reached when Atlantis was at its peak was far superior to our own. The people from Atlantis are the one who created Sphinx and pyramid of Egypt. The Atlanteans were spiritually evolved human being, they had access to more than three dimensions.
The reason why Scientific/Archaeologist community doesn’t believe that Sphinx is built around 10000 B.C is because it will defy Darwin’s theory of evolution. This is the reason why information about existence of Atlantis will be always opposed by Scientific community.
I would suggest you to watch this award winning documentary from NBC about Sphinx. It will change your thought about life and human existence.
If this video is not enough to satisfy your desire to know about life than my suggestion will be to read this book.