Stephen Wolfram

the simplest candidates that could conceivably have that property do have that property.

And that's what the principle of computational equivalence might suggest.

But this principle of computational equivalence, one question about it is, is it true for the physical world?

It might be true for all these things we come up with, the Turing machines, the cellular automata, whatever else.

Is it true for our actual physical world?

Is it true for the brains, which are an element of the physical world?

We don't know for sure, and that's not the type of question that we will have a definitive answer to because there's a sort of scientific induction issue.

You can say, well, it's true for all these brains, but this person over here is really special and it's not true for them.

And the only way that that cannot be what happens is if we finally nail it and actually get a fundamental theory for physics, and it turns out to correspond to, let's say, a simple program.

If that is the case, then we will basically have reduced physics to a branch of mathematics.

In the sense that we will not be, you know, right now with physics, we're like, well, this is the theory that, you know, this is the rules that apply here.

But in the middle of that, you know, right by that black hole, maybe these rules don't apply and something else applies.

And there may be another piece of the onion that we have to peel back.

But if we can get to the point where we actually have, this is the fundamental theory of physics.

Here it is.

It's this program.

Run this program and you will get our universe.

Then we've kind of reduced the problem of figuring out things in physics to a problem of doing some what turns out to be very difficult, irreducibly difficult mathematical problems.

But it no longer is the case that we can say that somebody can come in and say, whoops, you know, you were right about all these things about Turing machines, but you're wrong about the physical universe.

We know there's sort of ground truth about what's happening in the physical universe.