Wednesday, December 12, 2012

A Minimal Ontological Argument Without S5

1. Necessarily, everything that exists is either contingent or necessary. (Definition)

2. Necessarily, something exists. (Premise)

3. Possibly, nothing contingent exists. (Premise)

4. Therefore, something necessary exists. (From 1 - 3)

Reductio ad absurdum:

5. Nothing necessary does exists. (Assumption)

6. Necessarily, if nothing necessary exists, then it's possible for nothing to exist. (From 1 and 3)

7.  (6) contradicts (2).

8. Therefore, (5) is false and something necessary exists.


The argument is logically airtight.  If the premises are true, then there's no escaping the conclusion.  Premises (1) and (3) are either true by definition or true on any realistic account of ontology.  The key premise is (2).  Is it necessarily the case that something exists?  One could certainly defend cosmological arguments and the PSR, but I'd like to see another type of argument.  Can it be shown that "possibly, nothing exists" (possibility of ontological nihilism) is contradictory or absurd?


  1. Can it be shown that "possibly, nothing exists" (possibility of ontological nihilism) is contradictory or absurd?

    Maybe, but it strikes me that it can be shown that, if true, it is a completely vacuous statement, on the level of "orange shine donkey" Consider: if nothing exists, then there is a plausible case to be made that nothing is real. This would seem to include the affirmation that things like the laws of mathematics are not real - still more, socially constructed things like the rules of language would not be real. Therefore, if it is true that "necessarily, nothing exists", and the previous points are also true, then it seems that the statement becomes utterly meaningless. Not even wrong, if you like. Just a thought.

  2. I accept your argument because I hold to a form of realism with respect to abstract objects. After all, if literally nothing existed, it would still be *true* that nothing existed.

  3. This is somewhat off topic, but it concerns Ontological Arguments like Plantinga's I guess. Some atheists object by saying that "necessary existence" is not a great-making property, and that we have no reason to think it is so.

    But I was thinking, is the ability to "cause something," or the ability "to make use of one's powers" a great-making property? After all, what is greater, a God who can, at any time and any place, share his goodness with other beings or a God that fails to share his goodness with other beings?

    On one hand, “contingent existence” is not a GMP, because a being with CE can fail to exercise its ability to act or cause.

    However, if "necessary existence" entails the ability to cause or act without ever failing to do so, which I think is a GMP, does that mean that “necessary existence” is a GMP?

    In other words, if A entails B, and B is a GMP, does it follow that A is a GMP?

  4. Do you mean that if A entails B, and A is a GMP, then B is a GMP? That's the only way I can think it would be logically valid.

    I think you'll find more atheists denying the possibility premise (possibly, a maximally great being exists) than you'll find denying that necessary existence is greater than contingent existence. Some atheists will do the latter, but like you, I think it's just obvious that NE is greater than CE. Clearly a being that can act in all possible worlds is greater than one that can act in only one possible world.

  5. Here's another way of defending (2).

    If literally nothing exists in w1, then not even possibility exists in w1. However, whatever is possible is necessarily possible. Hence, if X is possible in w2, then it is possible in all possible worlds, including w1. This argument makes use of S5 in the form of "if possibly p, then necessarily possibly p."

    Moreover, if not even possibility exists in w1, then w1 is not possible! Or so it seems. :) This argument doesn't use any form of S5.