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But I do not think so. For if the rule for our universe is at all simple, then I expect that to introduce a new phenomenon, however esoteric, will involve modifying some basic part of the rule, which will also affect even common everyday phenomena.

But why should we believe that the rule for our universe is in fact simple? Certainly among all possible rules of a particular kind only a limited number can ever be considered simple, and these rules are by definition somehow special. Yet looking at the history of science, one might expect that in the end there would turn out to be nothing special about the rule for our universe—just as there has turned out to be nothing special about our position in the solar system or the galaxy.

Indeed, one might assume that there are in fact an infinite number of universes, each with a different rule, and that we simply live in a particular—and essentially arbitrary—one of them.

It is unlikely to be possible to show for certain that such a theory is not correct. But one of its consequences is that it gives us no reason to think that the rule for our particular universe should be in any way simple. For among all possible rules, the overwhelming majority will not be simple; in fact, they will instead tend to be almost infinitely complex.

Yet we know, I think, that the rule for our universe is not too complex. For if the number of different parts of the rule were, for example, comparable to the number of different situations that have ever arisen in the history of the universe, then we would not expect ever to be able to describe the behavior of the universe using only a limited number of physical laws.

And in fact if one looks at present-day physics, there are not only a limited number of physical laws, but also the individual laws often seem to have the simplest forms out of various alternatives. And knowing this, one might be led to believe that for some reason the universe is set up to have the simplest rules throughout.

But, unfortunately perhaps, I do not think that this conclusion necessarily follows. For as I have discussed above, I strongly suspect that the vast majority of physical laws discovered so far are not truly fundamental, but are instead merely emergent features of the large-scale behavior of some ultimate underlying rule. And what this

From Stephen Wolfram: A New Kind of Science [citation]