Decrypting the code

imported from http://maverickphilosopher.typepad.com/maverick_philosopher/2010/07/might-there-have-been-just-nothing-at-all.html

Could There Have Been Just Nothing At All?
No doubt, things exist. At least I exist, and that suffices to show that something exists. But could it have been the case that nothing ever existed? Actually, there is something; but is it possible that there have been nothing? Or is it rather the case that necessarily there is something? Is it not only actually the case that there is something, but also necessarily the case that there is something? I will argue that there could not have been nothing and that therefore necessarily there is something. (Image credit.)

My thesis, then, is that necessarily, something (at least one thing) exists. I am using 'thing' as broadly as possible, to cover anything at all, of whatever category. If I am right, then it is impossible that there have been nothing at all. The type of modality in question is what is called 'broadly logical' or 'metaphysical.'

Note that Necessarily something exists does not entail Something necessarily exists. I am not asserting the second proposition, but only the first. The second says more than the first. In the patois of possible worlds, the second says that there is some one thing that exists in every possible world, whereas the first says only that every possible world is such that there is something or other in it. The first proposition is consistent with the proposition that every being is contingent, while the second is not. So the first and second propositions are logically distinct and the first does not entail the second. I am asserting only the first.

What I will be arguing, then, is not that there is a necessary being, some one being that exists in all possible worlds, but that every world has something or other in it: every possible circumstance or
situation is one in which something or other exists. That is, there is no possible world in which there is nothing at all.

You can think of merely possible worlds as maximal or total ways things might have been, and you can think of the actual world as the total way things are. My thesis is that there is no way things might have been such that nothing at all exists. But if you are uncomfortable with the jargon of possible worlds, I can translate out of it and say, simply, that it is impossible that there have been, or be, nothing at all. As a matter of metaphysical necessity, there must be something or other!

The content of my thesis now having been made clear, I proceed to give a reductio ad absurdum argument for thinking it true.

1. Let S = Something exists and N = Nothing exists, and assume for reductio that N is possibly true.
2. If N is possibly true, then S, which is true, and known to be true, is only contingently true.
Therefore
3. There are possible worlds in which S is false and possible worlds in which S is true. ( From 2, by definition of 'contingently true')
4. In the worlds in which S is true, something exists. (Because if 'Something exists' is true, then something exists.)
5. In the worlds in which S is false, it is also the case that something exists, namely, S. (For an item cannot have a property unless it exists, and so S cannot have the property of being false unless S exists)
6. Every proposition is either true, or if not true, then false. (Bivalence)

Therefore
7. Every world has something in it, hence there is no world in which nothing exists.
Therefore
8. N is not possibly true, and necessarily something exists.

If you disagree with my conclusion, then you must either show that one or more premises are either false or not reasonably maintained, or that one or more inferences are invalid, of that the argument rests on one or more dubious presuppositions