I am not sure, David, I follow your reasoning. How can it be a non-sequiter to ask "How did the Universe begin ?" The fact that you do not wish to believe it started with the 'big bang' like a magician producing a dove from up an apparently empty sleeve does not invalidate the question or the answer. The fact is that it is the logical explanation for its existence as theory stands today, and if you wish to state that you might as well say God created everything in seven days, you may do so : it is a free society !