A Minimal Modal Ontological Argument for Naturalism

One can run a minimal modal ontological argument for naturalism with just two simple premises:  

1. Possibly, there is a necessarily existent extended thing (i.e., the two properties are compossible).

2. What's necessary doesn't vary from possible world to possible world.

3. Therefore, there is a necessarily existent essentially extended thing.

(2) follows from Axiom S5 of S5 modal logic, and most philosophers accept S5, so it's fairly uncontroversial. So the argument comes down to the plausibility of (1). But (1) just says that necessary existence and extension are compossible properties, which seems more plausible than the theistic possibility premise in the corresponding modal ontological argument for theism. For the truth of the latter premise requires acceptance of the compossibility of a large swath of exotic properties, such as omnipotence, omniscience, moral perfection, immateriality, and the capacity for creating individuals and/or stuffs out of nothing. Therefore, it appears that one has more reason to accept the minimal modal ontological argument for naturalism than the standard modal ontological argument for theism.

2 comments:

linford86 said...

Hm. As you know, there a variety of views in philosophy of physics according to which space-time -- and so spatio-temporal extension -- is not fundamental. Consider, for example, Sean Carroll's version of Everettianism, in which, ultimately, there only the universal wavefunction.

This suggests a different ontological argument:

1*. Possibly, there is a necessarily existent universal wavefunction (i.e., the properties of being neccessarily existent and of being a universal wavefunction are compossible).

2*. What's necessary doesn't vary from possible world to possible world.

3*. Therefore, there is a necessarily existent universal wavefunction.

Nonetheless, there seems to be a fairly intuitive reason as to why we should deny this argument, even if its not obvious which of the two premises we should deny. Unless I'm mistaken, we could propose the following argument for proving the necessary existence of any kind of entity that you'd like, so long as the property of being an entity of that kind is compossible with being necessarily existent:

1**. Possibly, there is a necessarily existent thing of kind K, where being necessarily existent and an instance of kind K are compossible.

2**. What's necessary doesn't vary from possible world to possible world.

3**. Therefore, there is a necessarily existent thing of kind K.

I think we should deny 3** and so we should deny the conjunction of 1** and 2**. At least one of 1** and 2** are probably false, but I don't know which one we should deny. One thought is that no concrete entity could be necessarily existent; after all, plenty of philosophers have denied that concreta could be necessarly existent. If so, since all instances of any kind are concreta, no instance of a kind could be necessarily existent, and so the property of being an instance of any kind is not compossible with necessary existence. If that's right, we should deny premise 1**.

exapologist said...

Great comment! I have those worries as well. I've written another version in a new post.

Review of Ekstrom's <i>God, Suffering, and the Value of Free Will</i>

  Kevin Timpe reviews the book for NDPR .