Science and mathematics are well suited for describing the "how"; details on what we can observe or theorize. Philosophy and theology are more concerned with the "why" (or you might say the "who"); the meaning or purpose of existence and how to live life for the greater good. So I totally agree with Livio that they do operate on parallel planes. Personally I find the "why" much more interesting than the "how".
Throwing the word "God" on a book about science and mathematics is a good tactic for grabbing attention, which is of course helpful in selling a book.
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