I write and lecture a lot about science and religion. A common question I get from religious believers is "How can something come from nothing?" They seem to think it's the final clincher proving the existence of God—or at least some form of supernatural creation. Of course, they don't say how God came from nothing. Or, if they do, they claim God always existed and so did not have to come from anything. But then, why couldn't the universe have always existed? In fact, modern cosmology suggests that it did—that the universe is eternal.