Do you understand what Bob said about background radiation? I don't understand what you are replying to. So the universe had a start. The only thing I know of that probably didn't have a start is existence itself, because non-existence only exists as a concept juxtaposed to the concept of existence. Reality has substance. Non-existence has zip. Something existed before the Big Bang or it was something out of nothing, a contradiction. So, where in all this is math leading the reality horse? And how much more top-down can you get than with reality exists, A is A? Everything, knowledge-wise, starts with observation. After induction, deduction, but I see the temptation to let the latter run off on its own resulting in all kinds of nonsense. --Brant This is my position as well. Causality assumes existence and is only possible within existence. To discuss the how is to enter into science and out of philosophy.