Taffer said:
But these new physical laws are only based on what we know about our own universe. This is not what I am talking about. Let me explain with an analogy.
I would prefer if you could explain it with not yet another analogy, but let's try and see...
Imagine that we are computer programs running in a very large computer generated virtual reality. This VR consists of the entire universe.
Since this terminology caused some trouble between you and CplFerro: what you call "universe", I call "world", reserving the term "universe" for the totality of everything that exists, that is, the sum of all world. So I would say: "Imagine that our world is just a VR within a computer simulation hosted in a computer in a superworld". But this is just a question of terminology, that is, not something very important.
Now imagine that you and I start thinking about the nature of the universe, which is to say the nature of the universe as we observe it. You can say "but I can imagine a different universe, because I can imagine different physical laws", but I would respond "this is not a different universe, nor are they new physical laws". I'll explain further. A computer program inside a computer generated VR can not, but its very nature, exist outside the computer.
It seems to me you are confusing "modeling" and "creating". I can model a world that is outside our world. I just can't create it, per definition, since I can't do anything outside our world, since if I could, this "outside" would be part of our world.
We can assume that we are the same; we are unable to exist outside the universe. This includes any way of gaining knowledge about what is outside the universe.
No, it doesn't include this. We are, per definition, unable to exist outside our world, but that doesn't mean that we are unable to get knowledge about what is outside our world. Assume we would stumble upon some data within our virtual world that says "PentiumIII". That would allow us to learn something about the superworld our world is part of, namely, that our world is running on a certain type of machine.
Now the computer programs do not know that they are, in fact, living inside a computer VR.
In your example, maybe. But not necessarily so. And even if they do not know, they may consider it. Like we are considering this possibility. And they can still model different worlds. Those models of alternative worlds would be, of course, still subprocesses within the VR, but they would be possible.
So they are unable to imagine a different universe. What I am talking about when I say a "different universe" is this: a different universe to these programs inside the VR would be that they are actually living inside our 'real' universe; they are no longer a program and are flesh and blood humans. However they can never imagine this as they do not know they are inside a computer to begin with.
They can never
be outside the box. But they can
imagine it.
Assume the people inside the VR built their own virtual computer that runs its own virtual virtual reality, containing its own inhabitants. And this virtual virtual world would contain another computer, simulating a whole world with all details. And so on and so on, infinitely (that would require an infinite computer, but such a world wouldn't be impossible).
I furthermore assume that all those virtual<sup>n</sup> realities are completely identical. Or, another alternative version, follow identical physical laws. Or, a third alternative, follow different laws.
In any such a world, it would be extremely surprising if the inhabitants of the basic VR, looking at an infinite chain of increasingly virtual worlds, would never ever imagine that they are living in a VR.
They might even argue that the rule of parsimony allow them to infer that they are living in a virtual world, and that the chain of virtual worlds contained within each other expands in both directions: that is, not only does every world includes another world, every world is also included in another world.
Otherwise, they would have to assume the existence of a world that is the "uppermost" world. Since they never observed such a world, Occam's law forbids them to assume that such a world exists.
Therefore, they conclude, they
know that their world is just a virtual reality.
Now lets think about us. Let us assume, for the moment, that there is something outside our universe. However, just like the computer programs, we cannot know the nature of this. Thus any 'new universe' we try to imagine is just an extrapolation of our old universe; it is not different in any significant way.
It seems to me that you agree that we can imagine different physical laws. But they wouldn't be, according to you, "different in any significant way". To me, that seems to be a completely arbitrary label.
New physical laws are not really new, they are just what we get when we imagine away our current laws. But what about new laws? For all we know, what exists outside our universe is another universe with entirely different physical laws, but it is impossible to imagine them.
And once again, you seem to say that we can't imagine new laws. I, on the other hand, would say that the really difficult part is
not to imagine new laws. Aristotle's or Newton imagined laws different from the laws of our world.