that follow [6, 7], my guess is that at the lowest level there will just be certain patterns of connectivity that tend to exist, and that space as we know it will then emerge from these patterns as a kind of large-scale limit.

And indeed in general what I expect is that remarkably few familiar features of our universe will actually be reflected in any direct way in its ultimate underlying rule. For if all these features were somehow explicitly and separately included, the rule would necessarily have to be very complicated to fit them all in.

So if the rule is indeed simple, it almost inevitably follows that we will not be able to recognize directly in it most features of the universe as we normally perceive them. And this means that the rule—or at least its behavior—will necessarily seem to us unfamiliar and abstract.

Most likely for example there will be no easy way to visualize what the rule does by looking at a collection of elements laid out in space. Nor will there probably be any immediate trace of even such basic phenomena as motion.

But despite the lack of these familiar features, I still expect that the actual rule itself will not be too difficult for us to represent. For I am fairly certain that the kinds of logical and computational constructs that we have discussed in this book will be general enough to cover what is needed. And indeed my guess is that in terms of the kinds of pictures—or Mathematica programs—that we have used in this book, the ultimate rule for the universe will turn out to look quite simple.

No doubt there will be many different possible formulations—some quite unrecognizably different from others. And no doubt a formulation will eventually be found in which the rule somehow comes to seem quite obvious and inevitable.

But I believe that it will be essentially impossible to find such a formulation without already knowing the rule. And as a result, my guess is that the only realistic way to find the rule in the first place will be to start from some very straightforward representation, and then just to search through large numbers of possible rules in this representation.

Presumably the vast majority of rules will lead to utterly unworkable universes, in which there is for example no reasonable notion of space or no reasonable notion of time.