Albuquerque said:
It seams to me that we must assume such kind of nothingness is possible in the first place and yet we don´t have any good reason to believe so...on its own premiss nothingness cannot be time dependent thus it does not follow a moment from where it can transit to something without contradicting its own conceptual terms...
(I apologise for my far from bright English which is not my first language)
They are still two separate arguments. In one, the debate is whether nothingness is itself a true possibility. In the other, the debate is whether nothingness actually existed (for a while, until something arose).
So in considering nothingness as a possibility, we can agree it must have no properties at all - no time, no space. It is not even an empty world.
And there is where the probability argument in fact slips up. It depends on some firm notion of countable worlds to get off the ground. And true nothingness could have nothing that smacks of a worldliness, such as change or development - any kind of temporal progression.
True nothingness, by its definition could never spawn an actual world. So the existence of something proves that there was never "a time of nothing". And yet is still seems an active possibility. There could still have been a nothing (as an alternative to our existence and how it came about).
To finally eliminate nothingness as even a possibility, further work is needed. We have to have an argument which says our world came about through this process, and logically this is the only kind of origin it could have had. And look, as the "complementary other" to existence, it exhausts all other possibilities. There is now no room for nothingness even as a logical possibility.
In other words, we employ the usual logic of metaphysical dichotomies.
Nothing vs something is a very weak kind of dichotomy. For the reasons discussed, it does not really work as the terms are not mutually exclusive and jointly exhaustive. No-thing is a simple negation, based on trying to subtract away all things (or actually, just the "some" that are taken to exist). And as you point out, we cannot finally subtract away time or space, or at least the potential for change, the potential for stability too, in any intelligible way. We can subtract to create an empty world, but not a non-world.
What we need is the kind of complex negation that is a strong dichotomy. In which the two polar alternatives cover every possibility and are definitely related by their very lack of relation - it is the total metaphysical exclusivity that exhausts the need for any further consideration of other possibilities.
As I said earlier in the thread, this leads us to some form of the arguments of Anaximander, Aristotle, Hegel and Peirce. Where what are opposed are vagueness and crispness, replacing the weaker thesis and antithesis of nothing and something.
The vague is a notion of a fundamental state that admits to development - the vague can always become something. As a state of pure potential, it is not a nothing (that is a possibility it excludes). But it is also as near a nothing as possible. Likewise, a pure potential can become anything. So it is also as near an everythingness as possible. It is an infinity of degrees of freedom as yet unconstrained, but by the same token, unformed.
Somethingness then becomes the emergence of constraints, of limits, of form. And the cause of this emergence employs all four of Aristotle's causes (whereas the "something from nothing" kinds of argument usually just appeal to some kind of local effective cause - a triggering event).
With the notion of vagueness, we can not only subtract away all things, we can also dissolve away any idea of space and time - so get rid of both the contents and the container to have less than an "empty world".
All sorts of things flow from this view. For instance, when now asking the question "why anything", the only alternative is that things might have remained forever vague. But this is illogical, forbidden, because constraints could also exist. The question can now be answered in terms of the inevitabilty of constraints.
Of course, you still have to construct that model. And people like Peirce, or Geoffrey Chew with his bootstrap approach to particle physics, have attempted such models. But at least the metaphysics gives a clear idea of what the model needs to be about - the development of global systems constraints.
So the Why Anything? argument is useful because it reveals the inadequacy of nothingness as a global concept (no-things can only be localised particulars of some crisply actual world). And even of effective causes as the way to get everything started (again, effective causes are only local and particular).
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