Where did the Big Bang come from

Last March, astronomers(working with data from a NASA satellite circling the Earth since 2001) concluded that time began 13.7 billion years ago, a trillionth of a second after the Big Bang. At that instant the universe expanded from submicroscopic to astronomical size in the blink of an eye. Why would it want to do that?

Thomas Nagel, the philosopher, recently pointed out that if we are to believe evolutionary explanations, and therefore that the necessary seed material (or energy) existed at the time of the Big Bang, we have to realize that there is no scientific explanation for the existence of that material in the first place. A complete understanding of evolution would involve answering a question as complex as evolution itself: "How did such a thing come into existence?" We have done nothing but push the problem one step back.