From a reader:
. . . I’m confused by some of your epistemic terms. You reject [in the first article referenced below] the view that we can “rigorously prove” the existence of God, and several times say that theistic arguments are not rationally compelling, by which you mean that there are no arguments “that will force every competent philosophical practitioner to accept their conclusions on pain of being irrational if he does not.“
Okay, so far I’m tracking with you. But then you go on to say that “[t]here are all kinds of evidence” for theism (not just non-naturalism), while the atheist “fails to account for obvious facts (consciousness, self-consciousness, conscience, intentionality, purposiveness, etc.) if he assumes that all that exists is in the space-time world. I will expose and question all his assumptions. I will vigorously and rigorously drive him to dogmatism. Having had all his arguments neutralized, if not refuted, he will be left with nothing better than the dogmatic assertion of his position."
So how is the atheist not irrational on your view, assuming he is apprised of your arguments? Perhaps the positive case for theism and the negative case against naturalism don’t count as demonstrations in a mathematical sense, but I’m not sure why they’re not supposed to be compelling according to your gloss on the term.
The term 'mathematical' muddies the waters since it could lead to a side-wrangle over what mathematicians are doing when they construct proofs. Let's not muddy the waters. My claim is that we have no demonstrative knowledge of the truth of theism or of the falsity of naturalism. Demonstrative knowledge is knowledge produced by a demonstration. A demonstration in this context is an argument that satisfies all of the following conditions:
1. It is deductive
2. It is valid in point of logical form
3. It is free of such informal fallacies as petitio principii
4. It is such that all its premises are true
5. It is such that all its premises are known to be true
6. It is such that its conclusion is relevant to its premises.
To illustrate (6). The following argument satisfies all of the conditions except the last and is therefore probatively worthless:
Snow is white
Either Obama is president or he is not.
On my use of terms, a demonstrative argument = a probative argument = a proof = a rationally compelling argument. Now clearly there are good arguments (of different sorts) that are not demonstrative, probative, rationally compelling. One type is the strong inductive argument. By definition, no such argument satisfies (1) or (2). A second type is the argument that satisfies all the conditions except (5).
Can one prove the existence of God? That is, can one produce a proof (as above defined) of the existence of God? I don't think so. For how will you satisfy condition (5)? Suppose you give argument A for the existence of God. How do you know that the premises of A are true? By argument? Suppose A has premises P1, P2, P3. Will you give arguments for these premises? Then you need three more arguments, one for each of P1, P2, P3, each of which has its own premises. A vicious infinite regress is in the offing. Needless to say, moving in an argumentative circle is no better.
At some point you will have to invoke self-evidence. You will have to say that, e.g., it is just self-evident that every event has a cause. And you will have to mean objectively self-evident, not just subjectively self-evident. But how can you prove, to yourself or anyone else, that what is subjectively self-evident is objectively self-evident? You can't, at least not with respect to states of affairs transcending your consciousness.
I conclude that no one can prove the existence of God. But one can reasonably believe that God exists. The same holds for the nonexistence of God. No one can prove the nonexistence of God. But one can reasonably believe that there is no God.
The same goes for naturalism. I cannot prove that there is more to reality than the space-time system and its contents. But I can reasonably believe it. For I have a battery of arguments each of which satisfies conditions (1), (2), (3) and (6) and may even, as far as far as I know, satisfy (4).
"So how is the atheist not irrational on your view, assuming he is apprised of your arguments?"
He is not irrational because none of my arguments are rationally compelling in the sense I supplied, namely, they are not such as to force every competent philosophical practitioner to accept their conclusions on pain of being irrational if he does not. To illustrate, consider the following argument from Peter Kreeft (based on C. S. Lewis), an argument I consider good, but not rationally compelling. I will argue (though I will not prove!) that one who rejects this argument is not irrational.
The Argument From Desire
- Premise 1: Every natural, innate desire in us corresponds to some real object that can satisfy that desire.
- Premise 2: But there exists in us a desire which nothing in time, nothing on earth, no creature can satisfy.
- Conclusion: Therefore there must exist something more than time, earth and creatures, which can satisfy this desire.
This something is what people call "God" and "life with God forever."
This is surely not a compelling argument. In fact, as it stands, it is not even valid. But it is easily repaired. There is need of an additional premise, one to the effect that the desire that nothing in time can satisfy is a natural desire. This supplementary premise is needed for validity, but it is not obviously true. For it might be -- it is epistemically possible that -- this desire that nothing in time can satisfy is artificially induced by one's religious upbringing or some other factor or factors.
Furthermore, is premise (1) true? Not as it stands. Suppose I am dying of thirst in the desert. Does that desire in me correspond to some real object that can satisfy it? Does the existence of my token desire entail the existence of a token satisfier? No! For it may be that there is no potable water in the vicinity, when only potable water in the immediate vicinity can satisfy my particular thirst. At most, what the natural desire for water shows is that water had to have existed at some time. It doesn't even show that water exists now. Suppose all the water on earth is suddenly rendered undrinkable. That is consistent with the continuing existence of the natural desire/need for water.
But this is not a decisive objection since repairs can be made. One could reformulate:
1* Every type of natural, innate desire in us corresponds to some real object that can satisfy some tokens of that type of desire.
But is (1*) obviously true? It could be that our spiritual desires are not artificial, like the desire to play chess, but lacking in real objects nonetheless. It could be that their objects are merely intentional. Suppose our mental life (sentience, intentionality, self-awareness, the spiritual desires for meaning, for love, for lasting happiness, for an end to ignorance and delusion and enslavement to base desires) is just an evolutionary fluke. Our spiritual desires would then be natural as opposed to artificial, but lacking in real objects.
Why do we naturally desire, water, air, sunlight? Because without them we wouldn't have come into material existence in the first place. Speaking loosely, Nature implanted these desires in us. This is what allows us to infer the reality of the object of the desire from the desire. Now if God created us and implanted in us a desire for fellowship with him, then we could reliably infer the reality of God from the desire. But we don't know whether God exists; so it may be that the natural desire for God lacks a real object.
Obviously, one cannot define 'natural desire' as a desire that has a real and not merely intentional object, and then take the non-artificiality of a desire as proof that it is natural. That would be question-begging.
My point is that (1) or (1*) is not known to be true and is therefore rationally rejectable. The argument from desire, then, is not rationally compelling.
As for premise (2), how do we know that it is true? Granting that it is true hitherto, how do we know that it will be true in the future? The utopian dream of the progressives is precisely that we can achieve here on earth final satisfaction of our deepest desires. Now I don't believe this for a second. But I don't think one can reasonably claim to know that (2) is false. What supports it is a very reasonable induction. But inductive arguments don't prove anything.
In sum, the argument from desire, suitably deployed and rigorously articulated, helps render theistic belief rationally acceptable. But it is not a rationally compelling argument.