experiences you've ever had. why? >> zero gravity was amazing. i could have gone on and on. being confined to a wheelchair doesn't bother me as my mind is free to roam the universe, but it felt wonderful to be weightless. >> larry: what, stephen, to you most hope people take away from your new book "the grand design? ?" in your opinion, it's a great book with a lot of important points. what is the most important point in the book? that science can explain the universe and we don't need god to explain why there is something rather than nothing and why the laws of nature are what they are. >> larry: what quality or lesson would you most like to pass on