So is it conceivable that the ultimate model for our universe could be based on a multiway system? At first one might not think so. For our everyday impression is that our universe has just one definite history, not some kind of whole collection of different histories. And assuming that one is able to look at a multiway system from the outside, one will immediately see that different paths exist corresponding to different histories.
But the crucial point is that if the complete state of our universe is in effect like a single string in a multiway system, then there is no way for us ever to look at the multiway system from the outside. And as entities inside the multiway system, our perception will inevitably be that just a single path was followed, corresponding to a single history.
If one were able to look at the multiway system from the outside, this path would seem quite arbitrary. But for us inside the multiway system it is the unique path that represents the thread of experience we have had.
Up until a few centuries ago, it was widely believed that the Earth had some kind of fundamentally unique position in space. But gradually it became clear that this was not so, and that in a sense it was merely our own presence that made our particular location in space seem in any way unique. Yet for time the belief still exists that we—and our universe—somehow have a unique history. But if in fact our universe is part of a multiway system, then this will not be true. And indeed the only thing that will be unique about the particular history that our universe has had will be that it is the one we have experienced.
At a purely human level I find it rather disappointing to think that essentially none of the details of our existence are in any way unique, and that there might be other paths in the multiway system on which everything would be different. And scientifically it is also unsatisfying to have to say that there are features of our universe which are not determined by any finite set of underlying rules, but are instead in a sense just pure accidents of history associated with the particular path that we have happened to follow in a multiway system.
In the early parts of Chapter 7 we discussed various possible origins for the apparent randomness that we see in many natural systems. And if the universe is described by a multiway system, then