God and physics or Who is this Kalam person, anyway?

[nameandnature]

Over at Ex-apologist's blog, the former apologist links to a paper and a response to it which straddle the boundary between physics and theology. I'm a sucker for this sort of stuff. The paper is J. Brian Pitts's Why the Big Bang Singularity Does Not Help the Kalam Cosmological Argument for Theism, and the response comes from William Lane Craig, who revitalised the Kalam argument for the existence of God.

There are some real physicists reading this, so I'd be interested to know what you think of this stuff. I've left a comment over on the ex-apologist's blog, which I've pasted below:

I love this stuff: it combines physics, philosophy and religion. I don't think Craig's response addresses Pitts's paper terribly well: they appear to be talking past each other. I have a physics degree gathering dust and a passing acquaintance with the philosophy of science, and I don't find Craig terribly convincing (but then, I'm also an ex-Christian atheist, so I wouldn't, would I?)

Craig seems to have misunderstood Pitts. Craig says the Kalam does not rely on a singularity but merely on the universe having a finite age, but as a matter of fact, Craig does appear to argue that the Big Bang singularity represent divine intervention, so Pitts's Cosmic Destroyer argument seems to have some force. When Pitts makes this argument, he accepts, for the sake of the argument, Craig's own claim that the past singularity of the Big Bang represents God's creative intervention, and asks why someone who accepts that claim would not also say that God intervenes destructively in black holes. The idea that God would do so probably seems silly to Christians, but Pitts says that on Craig's own argument, this feeling of silliness isn't well motivated. On the other hand, if the feeling of silliness is correct, perhaps Craig is wrong about singularities. A third possibility is for Craig to find some way to distinguish between the singularities, but Craig does not address this directly in his response.

Pitts's thoughts about possible other theories aren't necessarily an expression of Pitts's theological commitments (whatever those may be). The reference to van Fraassen is a clue (and the fact that this stuff is published in a philosophy of science journal): Pitts is talking about the arguments between scientific realism and more empiricist philosophies of science which owe something to logical positivism, such as van Fraassen's own constructive empiricism. He's taking a middle position: the unobservable objects posited by theories are meaningful but we ought to be careful about how far we believe they are real (van Fraassen says we can have no grounds to do so, though, contra positivism, we can accept that our theories meaningfully make such claims about unobservables; realists say there are grounds for believing in unobservables). Craig appears to be quite a bit more of a realist about General Relativity than Pitts, or indeed than working physicists like Sean Carroll.

The references to Bach-Weyl and so on are waved away (I'm no expert, but I think in that specific case, rightly, since as far as I can tell Pitts is talking about an early, failed attempt at a unified theory of gravity and electromagnetism), but the possibility of a theory which does not give lengths (durations) to curves should worry Craig, unless he is completely committed to GR. What does it mean to say "the Universe began to exist" on such a theory, or if the universe looks like Carroll thinks it does? Dennett: "What Professor Craig does, brilliantly and with a wonderful enthusiasm, is he takes our everyday intuitions—our gut feelings about what’s plausible, what’s counterintuitive, what couldn’t possibly be true—and he cantilevers them out into territory where they’ve never been tested, in cosmology where whatever the truth is, it’s mindboggling." (thanks to Daniel Fincke for that one).

Comments

[andrewducker]

It all seems remarkably silly to me.

[nameandnature]

I wonder about the silliness heuristic sometimes: clearly there are clever people who take some silly ideas seriously, so I worry I might be missing something if I don't look at them, but on the other hand there's a finite amount of time to look at stuff. Eliezer has some tips, but would probably regard theism as silly.

[andrewducker]

Absurdity is, as Eliezer (kind of) points out, just your subconsciousses way of pointing out that the suggest form of reality that has been suggested does not correspond with our existing experience.

Silliness is when people tie themselves in knots discussing said absurdity in attempts to either justify or discount it.

Err, well, this post I suppose. What else?

[wmconnolley.livejournal.com]

"William Lane Craig, who revitalised the Kalam argument for the existence of God." - the link, to wiki, is full of {{cn}}'s for various non-obvious "facts".

I liked He defines "begins to exist" as "comes into being," which appears to pointlessly replace one vague phrase with another vague phrase.

Re: Err, well, this post I suppose. What else?

[wmconnolley.livejournal.com]

Not to mentioon that Craig's arguements from infinity, at least as represented by the wiki article, are twaddle.

Re: Err, well, this post I suppose. What else?

[gjm11.livejournal.com]

The nearest thing I know of for a justification for the claim "whatever begins to exist has a cause" is that if you, like, imagine something not being there, and then, y'know, being there, well, ah, it seems like something must have made it happen, know what I mean?

And perhaps "comes into being" conjures up a picture that encourages that sort of crystal-clear thinking, whereas e.g. "exists at a set of spacetime points that doesn't include an infinite sequence whose pairwise intervals are negative and bounded away from 0" doesn't.

[simont]

I idly wonder if the "whatever begins to exist has a cause" people apply the same principle to spontaneous creation of particle/antiparticle pairs.

[gjm11.livejournal.com]

That's my favourite counterexample to the claim. Especially as it's just about the only example, apart from the beginning of the universe itself, of something actually beginning to exist (as opposed to already-existing stuff being rearranged).

[gjm11.livejournal.com]

Although of course it's not known that the creation of particle-pairs is really causeless. (One can say it's caused by the laws of physics, or something, but of course that's not a good line for the Kalamitous to take because it rather undermines their subsequent claim that "conceptual analysis" of the cause of the universe shows that it must be a person with, surprise surprise, roughly the attributes Christians traditionally ascribe to their god. :-) )

[(Anonymous)]

First cause argument has nothing to do with singularities. Aquinas pointed that out, oh, years ago. Point, missed (see what I did there?).

S.

[nameandnature]

The idea that the universe began to exist has something to do with Craig's version of the first cause argument. Though Craig rightly says that it need not have begun in a singularity, he also seems quite keen to defend theories which have singularities, so it does look like he thinks there's something significant about them.

If a first cause argument cannot be challenged by any sort of physical discovery or theorising, it seems the pretty empty to me: who are we to tell the universe what it must be like?

[(Anonymous)]

Then Craig needs to go back to Aquinas, or Aristotle, and think more deeply about what 'cause' means and how it doesn't necessarily have to do with time (and indeed can't, really, in the case of the first cause).

S.