Calhoun wrote:

Since PPC comes up often here, here is an interesting criticism of Feser's argument and use of PPC in it.

 
I just lazily skimmed through it, might read it more carefully later on. Is he sayi that it is possible for the first cause to only have universals eminently, as in, as a power to create them, and not as abstractions in a mind?

If so, then regardless of any responses to that, would it be possible or somethhing to have the power to create rationality without being itself rational? This is a more specific case of PPC than the one based solely on the creation of any things. We know there are thinking beings in creation and rationality, but can a non-thinking being have the power to create and sustain thinking beings and rationality? It seems absurd to me.

Also, if rationality is a power, then if the first cause is omnipotent shouldn't it also have rationality or the power of thought in some sense?

Miguel wrote:

From what I said about teleology I think modal collapse would not be an adequate answer to fine-tuning, should've made that clear. The main way out from FT would be a multiverse without Boltzmann brains, but there are some issues with the multiverse hypothesis as an explanation, I think.

Atheists can come up with three hypotheses to try to avoid creation ex nihilo.

A. Multiverse + eternal inflation

This has three problems:

1. It's inherent lack of scientific status makes it unacceptable even for some atheists.

2. The specific type of inflation consistent with the conclusions of Planck 2015 requires highly fine-tuned initial conditions to start.

See the irony? Inflation was originally postulated to avoid initial fine tuning, i.e. to enable the possibility that the universe began to exist in arbitrary, highly chaotic initial conditions. Now observations imply that in fact there was inflation, but of a type that requires initial conditions even more fine-tuned than those that atheist scientists originally tried to avoid!
 
3. Additionally, the well known Borde-Guth-Vilenkin theorem [1] states that any cosmological model which is inflating -- or just expanding sufficiently fast -- must be incomplete in null and timelike past directions, i.e. it cannot extend indefinitely into the past. So, it does not explain at the physical level how the universe came to exist.

B. Cyclic cosmology

This comes in two basic flavors, depending on whether entropy is reset or conserved at each bounce, with each flavor having a different refutation.

If entropy is reset to zero at each bounce, then all cycles start in the same initial conditions and therefore should evolve in the same way. But we know that the expansion of the universe in "this cycle" is accelerated and will last forever. Therefore there could not have been any previous cycle.

If entropy is conserved at each bounce, and there is a positive cosmological constant, as we know is the case, then there can be only a finite number of cycles, each of them of greater extension in time and volume than the previous, until there comes a cycle when the cosmological constant "takes over" and the universe starts to expand acceleratedly and irreversibly, which could be the case of the present cycle [2]. In contrast with the entropy-resetting flavor of the hypothesis, the refutation of this flavor refers only to its not explaining at the physical level how the universe came to exist.

C. Hartle and Hawking's no boundary proposal

Two 2017 studies [3] [4] show that this hypothesis leads to initial perturbations getting unsuppressed and out of control, which is grossly inconsistent with observations.


References

[1] Borde, Guth & Vilenkin (2003), Inflationary spacetimes are not past-complete.
https://arxiv.org/abs/gr-qc/0110012

[2] Barrow & Dabrowski (1995), Oscillating Universes.
http://adsbit.harvard.edu//full/1995MNRAS.275..850B/0000850.000.html

[3] Feldbrugge, Lehners & Turok (2017), No smooth beginning for spacetime.
https://arxiv.org/abs/1705.00192

[4] Feldbrugge, Lehners & Turok (2017), No Rescue for the No Boundary Proposal.
https://arxiv.org/abs/1708.05104

Last edited by Johannes (3/06/2018 10:07 am)

Another point that has not been mentioned is that immanent teleology aka physical intentionality commits one to a powers theory of modality. Press and others have shown though that from a powers theory + S5 (that all possibilities are necessary and thus not subject to change) one can derive the existence of an omnipotent necessary being.

This, rather than the Fifth Way, would be a better point to press against those who uphold immanent teleology and naturalism.

Miguel wrote:

DanielCC wrote:

Another point that has not been mentioned is that immanent teleology aka physical intentionality commits one to a powers theory of modality. Press and others have shown though that from a powers theory + S5 (that all possibilities are necessary and thus not subject to change) one can derive the existence of an omnipotent necessary being.

This, rather than the Fifth Way, would be a better point to press against those who uphold immanent teleology and naturalism.

 
Where has he shown this?

In the essay 'The Actual and the Possible' and in his book on powers. The nub of the argument is that if one accepts a powers theory and the claim that the total of contingent beings could have been different (that is that there could have been completely different contingent beings) then one ends up with a necessary entity with the power to bring this about.

The powers theory also arguably commits one to the PSR (though I think the latter is more fundamental)

Last edited by DanielCC (3/06/2018 4:35 pm)

Some empirical evidence maybe: defend the idea that no quantum deterministic model works?