While most of what you say seems right, I think the issue regarding Plantinga's Modal OA is a little more complicated, Given that Thomists reject that particular modal ontology, how far does mere heuristic semantics can take us? Do you think it suffices for OA that such semantics be merely useful or does it require that they really give us insight into correct metaphysics? 

And I guess some Aristotelians don't want to appeal to possible worlds even merely heuristically, they offer alternative semantics.  

Last edited by Calhoun (2/13/2018 2:39 pm)

Miguel wrote:

Personally, my problem with the OA as a standalone argument is how we can successfully argue for the possibility of God without using additional arguments. Contrary to the universe, contingent things etc which we come to know and interact with through our senses in our ordinary (and philosophical) lives, it is harder to discuss the modal possibility of a transcendent being such as God. If we can argue for the first premiss in the ontological argument, then we probably can also give a more direct, clearer argument for God's existence (e.g. Leibnizian cosmological arguments). I think the OA can be useful to perform a modal weakening of premisses in cosmological arguments (or other arguments for God's existence), e.g. Scotus's, Gale-Pruss, etc. If it's at least possible that the universe/contingent things could have an explanation, and that seems undeniable even to those who wrongly reject PSR, and that explanation is a necessary being, then that necessary being exists.

As a standalone argument, however -- which is how OAs have typically been discussed -- it is not very good, in my opinion.

I don't know about that.

In fact, every argument of natural theology need, at least, good developpment of metaphysic thesis which are front door of metaphysics systems, sometimes only one, sometimes more.
In the case of the ontological argument, you need to defend basics of a modal ontology and, also, what is the link beetween epistemic possibility and ontological possibility. If you can succesfuly defend that we posses a good guide to ontological possibility, then the ontological argument will work, and it's as hard as any other theological argument.
For example, I think that the cosmological argument is maybe harder on this point, especially the rationalist version: you need to defend a version of the principle of sufficient which is easy to accept, but enough to make the case that the necessary being that you've proved is God. That's clearly not an easy task.

"only to point out that what a lot of people care about is really more realist Scholastic Aristotelianism". That describes the position I lean to. Is the doctrine of the transcendentals more of a scholastic notion or a Thomistic flavour?

DanielCC wrote:

I actually think Plantinga's Modal Ontological Argumenty is more epistemically respectible than Thomism, the Total System. The latter relies on highly controversial and oblique metaphysical topics like the Real Distinction and what view of existence it entails (if it's the property view them it's in even worse shape). This isn't a worry to general Thomistic sympathiser though since most points of Thomism e.g. epistemology, soul-body relationship, God's relationship to the world, and many if not all of the Five Ways can be formulated without it. As long they have a sucessful natural theology and account of hylemorphic dualism they don't care so much about abstract issues re existence. (That is not meant as a negative against this people - only to point out that what a lot of people care about is really more realist Scholastic Aristotelianism)

Calhoun wrote:

While most of what you say seems right, I think the issue regarding Plantinga's Modal OA is a little more complicated, Given that Thomists reject that particular modal ontology, how far does mere heuristic semantics can take us? Do you think it suffices for OA that such semantics be merely useful or does it require that they really give us insight into correct metaphysics? 

And I guess some Aristotelians don't want to appeal to possible worlds even merely heuristically, they offer alternative semantics.  

Possible world semantics are only needed to express modal notions in the language of extensionalist logic though. Plenty of people, providing they admit that it makes sense to talk of modality, appeal to Plantinga's argument without accepting his account of possible worlds as conjunctions of Platonic propositions. Aside from maybe Lewis modal concretism the OA is neautral to what account of possible worlds one gives, if one feels the need to give one at all.

One can even just formulate the argument without talk of possible worlds all together (Malcom and Harteshorne, the individuals who revived the modal argument, did just that). Theists e.g. Scotus and Leibniz, have got on fine with the argument centuries before we had possible worlds. It's still the same general argument.

Regarding Aristotelianism, non-strict Thomist Aristotelian theists e.g. Lowe, actually tend to give the argument a fairer hearing than Thomists.

Miguel wrote:

Personally, my problem with the OA as a standalone argument is how we can successfully argue for the possibility of God without using additional arguments. Contrary to the universe, contingent things etc which we come to know and interact with through our senses in our ordinary (and philosophical) lives, it is harder to discuss the modal possibility of a transcendent being such as God. If we can argue for the first premiss in the ontological argument, then we probably can also give a more direct, clearer argument for God's existence (e.g. Leibnizian cosmological arguments). I think the OA can be useful to perform a modal weakening of premisses in cosmological arguments (or other arguments for God's existence), e.g. Scotus's, Gale-Pruss, etc. If it's at least possible that the universe/contingent things could have an explanation, and that seems undeniable even to those who wrongly reject PSR, and that explanation is a necessary being, then that necessary being exists.

As a standalone argument, however -- which is how OAs have typically been discussed -- it is not very good, in my opinion.

Although I think more needs to be done to justify the possibility premise the theist and (this includes the Thomist) is obliged to defend it any way. The standard way of defending God's possibility is by defending the coherence of the great-making properties*, something the theist will have to do any way since to deny them constitutes an ontological disproof of God. There are of course other forms of Ontological Argument i.e. those that reason from the nature of pure perfections to the compossibility of such properties and thus the possibility of an entity possessing them, that do not have this problem.

*One might say that the atheist can reply 'Sure, they appear coherent but this is not enough to justify belief in actual possibility, as for all we know they're not' but they can reply this way to anything which 'appears' coherent. Likewise the same response becomes avalible to the theist the next time the atheist attempts to object to any of the divine attributes - 'Sure, they appear incoherent but that is not enough to justify belief in their actual impossibility'.

(Nor do I think we are in that bad an epistemic position. We have direct acquaintance with value properties, with knowledge, and with power properties, something even the Thomist grants with their account of the Transcendentals. Far from being abstract this are probably some of the most fundamental features of the world and our experience of it)

 

No, they are not obliged to give a direct defense of the posibility of God or the coherence of great-making properties. They may need to defend it only in a dialectical context in which the coherence of God is being doubted. But if we know God exists because of another argument, then we indirectly come to know God is possible and coherent.

It will simply depend on how one asseses the plausibility of different theses. If I am more convinced that, e.g. PSR is true and the explanation of the universe is to be found in a being like God, then I am convinced that God exists and, indirectly, that He is possible. If someone finds e.g. reasons to doubt the coherence of great-making properties to be more plausible than PSR, certain arguments for the existence of God etc., then he might make that move. Otherwise we can just make a moorean shift on all such arguments. Which is why a direct defense of the coherence of God, although useful, is not necessary for theists.

Considering the OA as a standalone argument, the probability of the first premiss is equal to that of the existence of God. So it is not weaker than the conclusion.




Also, weekly reminder that existence is a predicate.

After having read a recent article (in Spanish) on the ontological argument by a strict-observance Thomistic philosopher, the flaw in modern versions of the argument from Malcolm, Hartshorne and Gödel is quite clear: they confuse logical possibility with physical possibility, or logical necessity with physical necessity, with "physical" used in the scholastic sense of "real" or "actual", not in the modern sense of "material".

It is clear that God cannot (in either the logical or the physical sense of possibility) come to exist, because in that case He would be contingent. Therefore,

- in terms of possibility, even though God's existence is logically possible, if He did not exist his existence would be physically impossible. But physical impossibility does not entail logical impossibility, just as logical possibility does not entail physical possibility.

- in terms of necessity, even though God's nonexistence it not logically necessary, if He did not exist his nonexistence would be physically necessary. But physical necessity does not entail logical necessity, just as logical non-necessity does not entail physical non-necessity.
 

Last edited by Johannes (11/03/2018 3:05 pm)