Friday, September 18, 2015

Necessary Existence

I forgot to post an update earlier in the month that my and Josh Rasmussen's book manuscript Necessary Existence was sent off to the publisher for review. This book contains a bunch of arguments, some of them developed on this blog, others by Josh alone, some in correspondence by the two of us, all of which contend that there is at least one concrete necessary being, where an entity is concrete if and only if it is possible that it causes something.


Philo Lehmar said...

Sounds exciting! Will there be material on the gap problem of the cosmological argument?

Alexander R Pruss said...

No, since our target is arguing there is a necessary being, not arguing there is a God. We happen to think there is only one concrete necessary being and it's God, but that's not a thesis of the book.

David Gordon said...

Do you know yet when the book will be published?

Alexander R Pruss said...

It's under contract, but there needs to be final review, and even if it's accepted, there will no doubt be revisions. All this will take time.

Alex Jones said...

Can we expect this volume to be released anytime soon?

Alexander R Pruss said...

We just got encouraging referees' reports. If all goes well, a final version will be done by December.

Michael Gonzalez said...

I'm really looking forward to this book! I would love a set of arguments to show that at least one necessary being exists. Personally, I've always thought you could go from that directly to a good argument that there can only be ONE necessary being, and that that unique necessary being must be omnipotent.

You start with this weak version of the PSR:

1) Whatever exists has an explanation of its existence, either in contingency on some external cause, or in the necessity of its own nature.

Then posit that omnipotence is possible, but that two omnipotent beings cannot logically co-exist. As a corollary of that, it seems to me that nothing could ever cause an omnipotent being to exist, since such a being would also have to be omnipotent, and then they would co-exist.

The conclusion follows something like this:

2) In the possible worlds in which an omnipotent being exists, it is not dependent on any external cause.

3) Therefore, in the worlds where an omnipotent being exists, it does so by the necessity of its own nature (disjunction on 1, 2).

4) If a being possibly necessarily exists, then it necessarily exists (S5).

5) Therefore, a single omnipotent being exists necessarily (3, 4).

The next step is to show that it is the only NECESSARY concrete entity, and that seems to follow from this:

6) Necessary entities are not dependent on any external being for their existence.
7) In worlds with an omnipotent being, EVERY other concrete entity is dependent on that omnipotent one for their existence (at least, for their continued existence).
8) Therefore, there is no concrete necessary entity other than the one omnipotent one (5, 6, 7).

Anyway, I'll keep refining this line of thought, but I'll definitely make use of your arguments for there being at least one concrete necessary entity at the start of such arguments (and probably in defenses of the ontological argument).

Michael Gonzalez said...

I guess 6 might be called into question (actually lots of the steps in it might be... it's just a sketch at the moment, and has been for years). But, it's an interesting line of thought, to me.