Reply #70: I have a general worry about this type of answer

[Stunster]

Currently popular scientific theorizing posits 'string theory' and a 'multiverse'. Let's think about that for a minute.

I'm not suggesting that string physics is incompatible with a multiverse, nor am I suggesting that a correct string physics might not one day be shown to entail the existence of a multiverse. But I am saying that string physics, in its current formulations, does not entail a multiverse. There are in fact millions and millions of solutions to string physics equations that would involve something much less than a multiverse.

I'm aware of one model in which the solution involves a brane of infinite dimension, which I suppose can be shown to suggest a multiverse (the Randall-Sundrum model), and Susskind and Linde who also propose multiverse models are now incorporating insights from string theory. But string theory as such, as currently understood, does not entail a multiverse, and some string theorists are even hopeful that string theory will render the multiverse hypothesis superfluous (for example, Brian Greene, author of THE ELEGANT UNIVERSE).

String theory itself is highly controversial within physics, of course.

But let's cut to the chase. The point I'd make is that there is no way string physics or any other physics can avoid positing an unobservable, spaceless, timeless, infinite reality of some sort. Let me explain why.

Let's suppose that string physics, or some other development in physics, becomes scientifically established, and is shown to entail a multiverse. Immediately we'd want to know why there is any such thing as this physics, and why there is any such thing as a multiverse. Well, there's two ways to go at this point.

One way (that favored by Greene) is to say that the physics will turn out to logically necessary and that this follows from the mathematics exhibiting it. But how would this ultimate theory establish the validity of mathematical reason itself---the very mathematical reason that underlies the ultimate theory?

After all, the construction of the theory would be presupposing the validity of the mathematical reasoning involved, and it would be suggesting that mathematical reason is valid not only for this universe, but for the multiverse as a whole. And why would this universally valid Mathematical Reason be such as to instantiate anything in physical reality, not least ourselves, who can appreciate and grasp and understand it? Or to put it another way, why is there something (even this multiverse generating mathematics), rather than nothing at all? Hawking famously asked why the equations would go to the bother of making anything like a universe, and one could ask the same thing about the string (or whatever) equations that make a multiverse. Why, in other words, would the equations be self-instantiating in physical reality. Maybe you'd need another equation for that.

One would seem to be left with the choice of either theism, or a form of mathematical Platonism, and in either case, one would be positing a non-physical unobservable something as being responsible for both the multiverse and our reasoning about it. Moreover, mathematics itself is an infinite abstract structure. And it's physically invisible.

The trouble with Platonism as an account of reason is that if the Platonic entity itself is suitably to be grasped by mind, then it's deeply puzzling why it should not be intimately connected with mind (or intellect, or consciousness), and in fact be the content of a mind, or intellect, or consciousness. We never encounter Platonic entities as freestanding objects---they are always encountered as contents of minds. But an infinite mental content, such as mathematics is, would need an infinite mind, or intellect, or consciousness to comprehend it.

There is a way around this problem though. And that is to invoke once again the principle of natural selection. It would go like this: We get this universe because it is naturally selected within a multiverse. And we get the multiverse described by the equations of string theory (or whatever the final theory is) because it is naturally selected within a multiverse of multiverses. And we get the multiverse of multiverses because it is naturally selected by a multiverse of multiverses of multiverses.... And so on, ad infinitum.

But either way, you have to end up positing a physically unobservable infinite. Either, Mathematical Reason. Or, an infinity of universes/multiverses.

But the point of going this route was to avoid having to posit a physically unobservable infinite. But the point turns out to be self-defeating. And we see this ahead of time. E.g. the Randall-Sundrum model posits an infinite brane. Obviously we could not observe an infinite brane, even if we had a reason to infer that there must be one. Well, similarly, we could not observe a theistic God, even if we had reason to infer that there must be one (as an explanation of mathematical order, rational consciousness, moral, aesthetic and religious experience, and the existence of a physical world intelligible to mathematical reasoning. Cf. Wigner's famous remark about the 'unreasonable' efficacy of mathematics). But if the natural selection principles themselves lead us to posit an unobservable infinite, how are they superior to the theistic hypothesis?

I have to laugh when atheists complain that God 'doesn't explain anything' and then are driven by science itself to posit things like infinite branes, and an infinity of universes, and maybe even an infinity of multiverses, for heaven's sake, etc---none of which our finite minds could grasp or observe, and which are of course forever so.

Then there's the issue of consciousness. Doubtless more conceptual work is needed on all sides. Even from a scientific viewpoint, I think more and more we are finding that notions such as 'information' are fundamental and irreducible. Philosopher David Chalmers talks about matter being information from the outside, and consciousness being information from the inside. One can think of God as self-subsistent Reason--one can conceptualize God as unlimited, pure information communicating itself to itself, which just is, or which eternally generates, Consciousness, and therefore also Value. It generates Value (goodness, love, beauty, etc) because this unlimited self-communicating, self-revealing information is eternally united in harmony with itself, and thus is eternally One and Whole. (These concepts are also partly inspired by and suggestive of St Augustine's theology of the Trinity, which he suggests we try to grasp on an analogy with the operations of intellect/knowledge and will/love of the mind.)

And if one runs with Chalmers' idea that information is matter from the outside, the reason we don't see God is not so much that God isn't physical---it's rather that God is infinite. God is the unlimited self-communicating rational consciousness that knows the mathematics of string theory (or whatever the ultimate theory is). Or, God is the infinite self-communicating consciousness that grasps the infinity of multiverses, or multiverses of multiverses, etc.

So the reason we don't 'see' God is that there's just too much information for anyone looking at this unlimited information from the outside to be see it---finite minds can only fully comprehend finite information. But 'inside' the unlimited information , it's infinite consciousness--God fully comprehends Godself---and thus all of reality is ultimately intelligible (though not by us), because God is an unlimited act of rational understanding and self-communicating information.

In short, if your epistemology requires observation and rational intelligibility, and yet your ontology is infinite or quasi-infinite, then you need an infinite mind to 'do' the observing and rational understanding of that ontology, which of course will include itself.

Science kind of gets there in the end, but I suspect religion had it essentially figured out a long time ago. :-)