Book review: Modern Physics and Ancient Faith

Modern Physics and Ancient Faith
by Stephen Barr (2003)

Trying to relate religion and science is a perilous enterprise; philosophy is supposed to be the glue that fits them together.  Professor Barr avoids many dangers by taking a limited goal.  Materialists, he says, often claim that science shows the universe looking more like materialism would expect it to look like than what religion would expect it to look like.  While not a proof of materialism, it would certainly count in its favor.  Barr contests this claim, saying that while it may have been true one hundred years ago, the last century of developments in physics, cosmology, and mathematics have reversed the situation, and the universe now looks much more like what a Christian would have expected.  Of course, the current picture may change again, and even if it doesn’t materialism would remain logically possible.  Still, the “natural reading” of things has moved markedly in our favor.

Barr focuses on a few claims that he treats as natural to the religious worldview:  that the universe had a beginning in time, that it was designed at least partly for our habitation, and that there is an immaterial element in human consciousness.  None of these are demanded by theism, but they have been assumed by theists commonly enough that it is a fair list of things to investigate.  [Materialism is then defined as disbelief in God and an immaterial component of the mind.  Thus, Roger Penrose is called a “materialist” even though he famously (notoriously?) believes in a Platonic realm of mathematical truth.]  The relevant discoveries of modern science are then the big bang theory, anthropic coincidences in the fundamental constants of the universe (that the universe is “fine tuned” for life), the Lucas-Penrose argument from Goedel’s theorem that the human mind cannot be a computer, and the Copenhagen interpretation of quantum mechanics (which seems to place the observer outside the system).  That none of these force a non-materialistic conclusion is granted, but the wild conjectures materialists seem driven to make show that they do fit somewhat uncomfortably in their system.

That’s the plan of the book.  Now some details about specific parts.

I’m not sure, after inflationary theory, that the universe having a beginning is necessarily the most natural assumption anymore, so I would actually call that one a tie for materialists vs. religious.  Barr is very good on showing that a quantum creation of the universe doesn’t vitiate the cosmological argument, because the zero-universe vacuum state is not a metaphysical “nothing” but is already the state of a system with a great deal of structure (non-necessary structure, freely specifiable by the theorist).  Also that having a multiverse / string landscape doesn’t really answer the “fine tuning” design argument, because one must specify the laws of physics just right to get an acceptable multiverse.  This is an interesting and important point, one I think probably true, and I would have liked to hear more how generic appropriate multiverses are for general Lagrangians.  I was pleased to see him making an argument that I have also made, that evolution (and, more generally, the assembly of stars, planets, crystals, etc) is not about order emerging from absolute chaos, but about order arising from deeper order.  (He even provides a sort of measure of order, which I failed to do, based on symmetries.)

The discussion of the argument from Goedel’s theorem is admirably clear.  I was convinced of its power after reading John Searle’s critique of it, in which Searle is willing to reject the validity of mathematics to avoid its conclusion.  That is what asserting that our minds are inconsistent (not merely fallible–I’m grateful to Barr for making the distinction clear to me) formal systems amounts to.  The conclusion that our minds are not formal systems, not purely algorithmic, not computers, is certainly remarkable, but I would not conclude that there is anything immaterial about the mind’s operation.  The algorithmic model may well be an overly narrow model of what a materialistic brain could do.  Barr’s point, though, is his usual modest one:  the evidence confirms religious expectations.

I admit that I am one of those people Barr mentions who refuses to grant consciousness some unique role in quantum mechanics out of sheer prejudice.  However, Barr holds a somewhat subjective version of the Copenhagen interpretation–going so far as to claim that a system can have multiple wavefunctions, one for each observer’s state of knowledge, which while not a fringe view is probably not the majority position (not mine:  I’m much more of a wavefunction realist; only density matrices have probabilities from observer ignorance)–which is in tension with his argument that quantum mechanics shows there to be something special about consciousness.  It seems to me that wavefunction collapse has to be an objective thing to make a claim like that.  What seems more consistent with his own reading of quantum mechanics is that observers play a distinct role in it not because they are special in reality but because they are special in the formulation of the theory; it’s a theory about outsiders’ observations, not a theory of reality as a whole.  This issue aside, I agree with Barr’s arguments against the many-worlds interpretation, against existing pilot wave theories, and against the idea that decoherence somehow makes all these problems go away.


5 Responses

  1. Materialists, he says, often claim that science shows the universe looking more like materialism would expect it to look like than what religion would expect it to look like.

    This seems unpromising. To do such an argument properly, you have to successfully imagine what a Materialist with no actual experience of material reality would reasonably think material reality was likely to look like (same for theist). This seems about as feasible to conduct as Rawls’s thought experiment. It seems like there’s a self-contradiction in the set-up.

  2. “I’m not sure, after inflationary theory, that the universe having a beginning is necessarily the most natural assumption anymore, so I would actually call that one a tie for materialists vs. religious.”

    Whoa, man, real bad take! Please read some William Lane Craig.

    “Inflation” is like neo-Darwinist evolution. It needs to be assumed to make the system work. You will grow a long white beard before Alan Guth gives you a description of a physical mechanism for how it works. What is the inflaton field? Name the laboratory where it has been observed? Crickets.

  3. I don’t understand how a material-appearing universe helps the materialist case. I don’t think very many people seriously consider that the universe is not material-surely the main culprit for this kind of thinking is Descartes. The error of the materialists is not that there is matter (whatever it is, and that has not been demonstrated), but that there is nothing else.

    It seems to me that the desperate multiverse hypothesis, one so absurd that, if true, it would immediately collapse upon being proven, at present fails Ockham’s Razor. Also, is it not just an attempt to kick the ontological can down the road?

    Aquinas did not belive the Universe need be finite. It seems to me this Dark Matter/Energy hypothesis is merely cooking the books for the present theory.

    Anyway, what do we know? What can we know? It’s all just speculation. If one wants to believe something, the only thing not built on sand is Revelation.

  4. […] universe a finite size, we’re presumably talking about non-trivial topologies.  Stephen Barr takes up this question for (if I recall correctly) a closed, spatially universe, and finds that, no, the […]

  5. John Q Public,

    I’m actually pleased by your skepticism. I teach a course on cosmology at my university, and I refuse to cover inflation because it’s too speculative. I do think that the “naturalness” of assuming a t=0 singularity is different now than it was 50 years ago. Then, one could invoke singularity theorems whose only escape was to assume “crazy” equations of state with negative pressure. Now such things don’t seem so crazy.

    1) There is evidence for a nonzero cosmological constant (dark energy), which acts like the inflaton’s energy density, although much weaker. So, stuff like that probably does happen.

    2) Although I don’t believe (or disbelieve) in inflation, I admit that the theory was invented to solve other problems, so shouldn’t be seen as an ad hoc invention to remove an unwanted singularity. The ingredients of the apparatus whereby it is supposed to happen (scalar field, spontaneous symmetry breaking) occur in several other areas of physics. It’s a live possibility.

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