Archive for April 10th, 2022


How about that Kalam argument?

While we’re talking about philosophical arguments for the existence of God, we should apparently consider the so-called Kalam argument.

In its simplest form it’s nice and short:

  1. Whatever begins to exist has a cause of its beginning.
  2. The universe began to exist.
  3. Therefore, the universe has a cause to its beginning.

This is, obviously, an argument for the existence of God, only if God is defined as “A cause of the beginning of the universe” and nothing further, which doesn’t seem all that significant, but still. There are further associated arguments attempting to extend the proof more in the direction of a traditional (i.e. Christian) God, being “personal” and all, but let’s look at the simple version for now.

I think it’s relatively straightforward that the conclusion (3) follows from the premises (1) and (2), so that narrows it down. Now, are (1) and (2) true?

First we should figure out what we mean by “the universe”, because that matters a lot here. Three possible definitions occur immediately, in increasing size order:

(U1) All of the matter and energy that’s around, or has been around as far back in time as we can currently theorize with any plausibility. All of the output of the Big Bang, more or less.

(U2) Anything transitively causally connected in any way to anything in U1. Everything in the transitive closure of past and future light-cones of me sitting here typing this (which is, at least arguably, the same as everything in the transitive closure of past and future light-cones of you standing there reading this).

(U3) Anything in any of the disjoint transitively-causally-connected sets of things that are picked out in the same way that U2 is, starting from different seed points that aren’t transitively-causally-connected. The “multiverse”, if you will, consisting of all those things that aren’t logically (or otherwise) impossible.

It’s interesting to note here that “the universe” as used in the Kalam can be at most U1. This is because nothing outside of U2 can be causally connected to, can create or cause or otherwise have any effect at all on, anything in U2. Anything that claims to be a cause of U2 or U3 is either not actually a cause, or is part of U2 or U3 by virtual of being causally connected to it.

This works, I think, via (2) in the argument above; U1 might plausibly be said to have begun to exist, but it’s hard to see how U2 or U3 could.

Or, I dunno, is that true? We can certainly imagine U2, that is, this universe right here, somewhat broadly construed but still undeniably this one, did just start up at some time T0. That it could, I suppose, turn out to be a fact that at all times T >= T0 there are some facts to write down about this universe, but at times T < T0 there simply aren’t.

The reaction of Kalam proponents to that suggestion seems to be just incredulity, but in general I don’t see anything wrong with the idea; a universe simply coming into being doesn’t seem logically contradictory in any way. We can certainly write down equations and state transitions that have a notion of time, and that have well-defined states only at and after a particular time; it’s not hard.

So I guess, even if the Kalam must mean U1 by “universe” even in its first premise, (1), there’s no strong reason to think that (1) is true even then. This universe right here, this collection of matter and energy, could have just sprung into existence eight billion years ago or whatever, without any particular cause. Why not?

Premise (2) is less ambitious, and therefore more plausible. Did this particular batch of matter and energy, U1, begin to exist at some time? Could be. I mean, I can’t prove it or anything, and neither can anyone else, but I might be willing to stipulate it for the sake of argument.

(Even U2 might have, although the Kalam proponent probably has to disagree with that: since they want to have a backwards-eternal God creating U1, that means that that God counts as part of U2, which means that U2 is backwards-eternal, and never came into being. So the Kalam folks are still stuck with U1.)

U3 has the interesting property that it doesn’t have a common clock, even to the limited relativistic extent that U1 and U2 have common clocks. Since U3 contains disjoint sections that have no causal connections to each other, it’s not really meaningful to speak of the state of U3 at “a” time, so referring to it beginning to exist (i.e. at “a” time) turns out not to really mean anything. I think that’s neat. :)

If we’re willing to stipulate (1) and (2) as long as “the universe” means only U1, the conclusion isn’t very powerful; we find out only that this particular batch of matter / energy that existed shortly after the Big Bang (or equivalent) must have been caused by something. And fine, maybe it was, but if it was that something was just some earlier and likely quite ordinary piece of U2. Calling that “God” just because it happens to be so long ago that we can’t theorize about it very well seems very far removed from what “God” is usually supposed to mean.

I’ve read various things on the Kalam argument, including the Craig piece linked above, and the counterarguments both don’t seem to actually understand physics and cosmology very well, and are mostly of the “proof by incredulity” variety; Craig writes, for instance,

To claim that something can come into being from nothing is worse than magic. When a magician pulls a rabbit out of a hat, at least you’ve got the magician, not to mention the hat! But if you deny premise (1′), you’ve got to think that the whole universe just appeared at some point in the past for no reason whatsoever. But nobody sincerely believes that things, say, a horse or an Eskimo village, can just pop into being without a cause.

— William Lane Craig

“Worse than magic” is hardly a logical argument, it’s just ridicule. And to state as a raw fact that no one seriously believes the argument one is attacking is, again, content-free. (The bit about Eskimo villages is a silly evasion; what may have come from nothing is for instance an unimaginably hot and dense ball of energy, not a horse. But even for a horse, expressing incredulity that one might appear spontaneously is not a logical argument; more work is required!)

This reminds me of the rather popular fundamentalist Christian statement that everyone knows deep down that God exists, and atheists are simply in denial. This is of course false and silly.

This also reminds me, now that I think of it, of an excellent lecture that I saw the other week, “God is not a Good Theory“. Among other things, the speaker here makes a similar move to my positing a universe that simply springs into being and seeing no contradiction in it; he describes various simple universes and shows that they can be explained perfectly well with no reference to any external God. “All I need to do is invent a universe that God does not play a role in” (a bit before the 10 minute mark). He also talks about the issue of causes with respect to the universe, and briefly mentions the Kalam. Definitely worth a listen.

On the Kalam in general, then, I find it extremely non-compelling. It doesn’t even have a sort of verbal paradox in it to have fun with, the way the Ontological argument does; it’s just weak. So I do wonder why it’s so popular. Thoughts in the comments are most welcome.