We believe human begins have existed for only a small fraction of cosmic history, because human race has been improving so rapidly in knowledge and technology that if people had been around for millions of years, the human race would be much further along in it's mastery.
Stephen HawkingA model is a good model if first it interprets a wide range of observations in terms of a simple and elegant model, and second if the model makes definite predictions that can be tested, and possibly falsified, by observation.
Stephen HawkingAs we shall see, the concept of time has no meaning before the beginning of the universe. This was first pointed out by St. Augustine. When asked: What did God do before he created the universe? Augustine didn't reply: He was preparing Hell for people who asked such questions. Instead, he said that time was a property of the universe that God created, and that time did not exist before the beginning of the universe.
Stephen Hawking