To me, this story is ultimately a discussion about the merits of knowledge and the merits of faith. The main character, first as a way to escape his situation and, later on, out of his own curiousity, becomes wrapped up in the search for a perfect understanding of how the universe works. However, along the way, he comes to learn that simply knowing that the universe works (essentially having faith in it), is just as, is not more, rewarding. In the end, the obsessive search for perfect knowledge of the universe proves to be self-destructive, while perfect faith that it does work proves to be freeing.
A lot of other things happen here, of course, but they're all too complicated to go into here. Suffice to say that true enlightenment also leads to learning that Elton John is truly awesome. I'll let you ruminate on that, while I go do enjoy the rest of Friday night.