Wednesday, September 03, 2008

A Necessary Being or Just a Collection?

In Chapter 7 of his Metaphysics (paperback, second edition), Peter Van Inwagen discusses the cosmological argument for the existence of a necessary being. He critiques traditional formulations which invoke the Principle of Sufficient Reason (PSR), and then presents some versions which rely on premises weaker than the traditional PSR. He thinks some of these versions have more merit (but none support a truly compelling argument in his view).

Below I look at one of the versions he discusses, which I found interesting and helpful for the purpose of exploring an argument I’ve been favoring. A key premise in both arguments has to do with whether the sum of everything that exists is actually an entity or being in its own right.

The first premise of the argument from Van Inwagen’s book relies on the following principle: “Every being has this feature: the fact that it exists has an explanation” (p.125). If we accept this principle then, Van Inwagen argues, it is plausible to suppose that here are no beings which are both independent and contingent. To be independent means there can be no explanation in terms of other beings: therefore, given that we demand some explanation for existence, the only answer can be that the being’s non-existence must be impossible. Its existence is necessary rather than contingent. It follows that we can construct what might be called a Monist or Pantheist cosmological argument (my labels):

Monist or Pantheist Cosmological Argument (adapted from Van Inwagen, p.125):

1. There are no independent and contingent beings (premise)
2. There is a being which is the totality of all beings: the world (premise)
3. The world is an independent being (follows from 2)
4. The world is not a contingent being (from 1 and 3)
5. The world is a necessary being (follows from 4)

I think there are good reasons to accept premise 1, but I want to discuss here the fact that even if one accepts it, many would reject the second premise. As Van Inwagen explains, a naturalist typically has no problem seeing the contingent objects in the world as mutually dependent, without any need to postulate a world-being. Traditional theists also reject premise 2, since they see the necessary being as being distinct from its contingent creation. When it comes to our actual world, I also would reject premise 2: I don’t see a good reason to consider the totality of things an additional fundamental thing (I have a post related to this topic here).

The form of this argument, however, helped bring out an implied premise in my own modal realist version of the cosmological argument (first sketched here). This is the premise that the sum of all metaphysical possibilities is a kind of totality-entity in a way that the sum of all actual things is not.

Let me lay out the argument as follows (note that while I will use the term “beings” to be consistent with the discussion above, this would not normally be my choice):

Modal Realist (or Panentheistic) Cosmological Argument:

1. There are no independent and contingent beings (premise)
2. Modal Realism is correct: all possible as well as actual beings exist (premise)
3. There is a being which is the totality of all beings: let’s call this the “megaverse” (premise)
4. The megaverse is an independent being (follows from 3)
5. The megaverse is not a contingent being (from 1 and 4)
6. The megaverse is a necessary being (follows from 5)

So the question I want to ponder is this: is premise 3 here more defensible than the similar premise 2 in the earlier argument? I think so, but I haven’t argued directly for this before.

My preliminary thoughts go something like this.

Certainly, the megaverse is metaphysically exhaustive in a way that the actual world is not, and so has a better claim to independence and necessary existence. But could it just be a “mere” collection of possible and actual beings rather than a totality entity/being?

Recall that in David Lewis’ model of modal realism, the set of possible worlds is indeed a mere collection. For Lewis, each world is causally distinct (the actual world is simply the one we find ourselves in). In my preferred model, on the other hand, there is an intimate connection between the actual and the possible at the level of each individual event. Each causal event is an actualization of a possibility. So there is a continual closeness or adjacency therefore between what we see as actual and what is possible. The actual “world” is a causal network of events embedded in a larger framework of possible events (more related discussion here). So the “megaverse” is not a collection of distinct worlds, but is better seen as this transcendent framework which our ever-evolving actual “world” fits into.

Still, this doesn’t seem to rule out that at the level of events (rather than “worlds”); we could view the megaverse as a “mere” collection.

I’ve been scratching my head on this, and have some more thoughts, but I’ll save them for a follow-up post.

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