He makes the argument that there are still things that science can't explain (consciousness, emotions, hope, etc.) and therefore a pure science worldview doesn't make sense. Until we can fully explain things, including the reason they happen, then religion has a place in human society. In his view, science cannot be a replacement for religion because it does not answer the "why".
So 500 years from now, with science still not able to create or explain consciousness, not able to recreate the big bang ( on a small scale of course ), will science state with certainty that God is the answer?
Here on earth, it seems impossible that humans would be the only life form to develop intelligence. Shouldn't natural selection produce smarter and smarter prey and predators? Primates fight each other. The first one smart enough to find a club and use it as a weapon would have a natural selection advantage over others.