I do not think your article makes a solid case for point (2): The universe began to exist. Actually, I do not think such a case can be made other than based on good science, i.e. science validated by empirical observations. 

To note, the observations needed to make such a case are indeed available, and contrary to what many could believe, the decisive observations are not those which attest to the Big Bang, but those since 1998 which attest to the acceleration of the expansion of the universe. I can expand on the subject if anyone is interested.

Last edited by Johannes (7/10/2015 9:20 pm)

Alexander wrote:

I think Ben's argument for (2) needs a bit more work (e.g. look at some objections and answer them), but at base it seems a compelling thought experiment, and shouldn't be dismissed simply because it isn't physics.

An earlier, more detailed/technical version of this argument was published a little over a year ago in Phil. Christi. I've uploaded a final draft of that work (with permission) to the PhilPapers archive, so that it is freely available for download here. That said, this argument is still new and has, so far as I know, yet to engender a response in the literature. In the more recent paper, I've tried to streamline this argument a bit for greater readability and ease of comprehension.

Alexander wrote:

DanielCC wrote:

Out of interest why do you focus on the Tristan Shandy scenario as preferred justification of temporal finitude as opposed to, say, the physical impossibility of Hilbert’s Hotel scenarios?
 

Obviously I can't speak for Ben, but I've never found the Hilbert's Hotel paradox convincing. It seems to begin by treating "infinity" as you would a specific (and hence finite) number, then demonstrating the obvious absurdities that result from this treatment. It also seems to rely more on intuitive "strangeness" (which could easily result from the human inability to properly think about infinity) than actual impossibility. Perhap's I'm mistaken, but this has always been my reading.

Okay, oddly my reaction erred in the other direction. I would dispute the problem with treating infinity as a specific number though: mathematicians work with specific infinites, some larger than other, all the time in Set Theory and other disciplines, and have been doing so for decades now since Cantor's theories first became commonly accepted. A good number of people do think about the infinite on a daily bread-and-butter basis. So I would say the intuitive strangeness follows from our knoweldge of the infinite plus that of the nature of the physical world (this is where I think it's more open to challange).
 
(I prefer Cantor’s term Transfinite for higher than finite numbers but that doesn’t matter here)

Last edited by DanielCC (7/11/2015 9:20 am)

Greetings DanielCC!

DanielCC wrote:

Out of interest why do you focus on the Tristan Shandy scenario as preferred justification of temporal finitude as opposed to, say, the physical impossibility of Hilbert’s Hotel scenarios?

This is a good question. In my opinion, the oddities associated with introducing the concept of infinity in the actual world, as reflected in various thought experiments like that of Hilbert's Hotel (or those suggested by ancient and medieval philosophers like Philoponus, al-Ghazali, and St. Bonaventure), are probably logical absurdities if they are genuine absurdities at all. However, unlike ancient and medieval philosophers, we now know that the concept of infinity, as carefully developed in modern mathematics, doesn't involve any such logical absurdities. This is why Craig has been driven to say that scenarios like Hilbert's Hotel are metaphysically absurd even if they are not also logically absurd, but I remain unconvinced on this point. In particular, it seems more likely to me that these scenarios only seem odd to us because we are accustomed to thinking in finite categories and not infinite ones.

On the other hand, the Tristram Shandy scenario (as analyzed by Robin Small in the 80s) is, in my opinion, doing the right sort of thing, though a bit more work remained to be done.

Secondly as to arguments from modern cosmology surely one would give as support the application of Vilenkin’s theorem to multiverse scenarios?

But even if the BGV theorem can be used to show that the multiverse had a beginning, one could always speculate that, perhaps, this multiverse arose out of some other multiverse with possibly different laws of physics that are not incompatible with an infinite past, etc. Also, this line of reasoning won't necessarily conclude to an uncaused cause since the cause of the multiverse might still be temporal and have a beginning of its own (hence also a cause of its own). I discuss these sorts of problems in the paper.

The real problem here, I think, is that a successful kalam cosmological argument needs to argue for the beginning of the universe, broadly conceived as the entirety of the temporal world; however, modern physical cosmologists tend to argue for the beginning of the universe (to the extent they do at all) in a sense that is too narrow for the purposes of the kalam argument. If what needs to be explained is the beginning of the entire temporal order (and not just the temporal order so far as we know about it), then the cause would have to be timeless (for reasons known to Aquinas et al.), and there can be no such talk of an earlier reigme of the physical universe/multiverse in this case.

Last edited by Ben (7/11/2015 4:04 pm)

DanielCC wrote:

Again true but I don't see why this is a problem per say. Since the opponent has ceded the temporal finitude issue even if the cause of the multiverse is temporal we will be forced to posit an atemporal cause at some point in the series, so why not for parsimony's sake do it there?

I suppose you could, but now what's really doing the philosophical work is the argument against a countably infinite series of consecutive finite temporal intervals that recede into the past and not developments in modern physical cosmology; in which case, one might as well run the kalam argument with the broader conception of universe that I use in the paper. In a sense, the whole point of invoking modern physical cosmology in this context is to provide an independent source of evidence for the second premise apart from any purely philosophical considerations.

Still, you're touching on an interesting point here. In a sense, one can argue from the existence of any mundane temporal entity to the existence of a timeless entity via repeated application of the argument against a countably infinite series of consecutive finite temporal intervals that recede into the past in much the same way Thomistic arguments proceed from the existence of mundane entities to an entity whose essence is its "act" of existence. People who have more energy for this sort of thing then I do right now might be able to bring all these different puzzle pieces together into a more robust/satisfying philosophical theology.