This is a follow-up to this post. To some extent it will be repetitive of what was in that post, and I beg the reader's indulgence for that repetition. But the argument I am answering has surfaced yet again (never mind where), and it just has so many things wrong with it that I have decided to take another whack at it, in the hopes of unconfusing anybody else who has been confused by it.
The argument goes roughly like this. (No, I'm not precisely quoting anyone. I am paraphrasing.)
Suppose that God revealed himself by a sign or wonder, such as by speaking from the heavens, by raising Jesus from the dead, or even by putting some words into an unlikely place, such as writing "Yahweh alone is God" in the stars or in the cell. Such an event would not be taken by an atheist to be from God. The atheist would decide that both he and everyone reporting the event to him were massively hallucinating rather than conclude that the event was really evidence of the existence of God. Hence, signs and wonders can be evidence of the activity of God only to those who already believe on other grounds that God exists. Therefore, they do not constitute independent evidence that God exists. Therefore, we shouldn't make arguments first to atheists from signs and wonders. Instead, we should convince them first that God exists by arguments such as philosophical arguments from natural theology.
Let me try to break down a few of the many things wrong with this argument.
First, this argument wrongly assumes that something cannot constitute independent reason to believe something I already believe. That isn't true. Suppose that I get ten e-mails that appear to be from my friend Jeff. Regardless of what order the e-mails come in, each one provides some independent reason to believe that Jeff exists. It is not as though, once I already believe it, the new e-mails no longer provide independent reason for believing in his existence. That probability just gets higher and higher as I receive additional e-mails. It's true that I'm more prone to conclude that a new e-mail is from Jeff if I already believe that Jeff really exists and isn't a spam-bot, but it doesn't follow that the additional e-mails are doing no work to support the proposition, "Jeff exists" simply because they happen to come later in the series. In fact, they obviously do provide additional reason to believe that Jeff exists, a reason that has its own force.
Second, this argument, consistently applied, would have made it impossible for the revelation of Yahweh to "get off the ground" with the people of Israel, because it would always have required previous evidence for Yahweh's existence before His self-revelation could get started. What we find in Scripture is that God revealed Himself to His people by signs and wonders from the outset. They didn't require or receive a philosophical prolegomenon. Rather, God was the God who brought them up out of the land of Egypt and out of the house of bondage. God made the bush burn. God told Moses to make it clear to the people that he was truly a messenger by giving Moses the power to do signs and wonders. If it were never possible to take signs and wonders to be from God if one didn't have a philosophical prolegomenon, then the specific revelation of Yahweh could never have happened.
This has a parallel in human relationships. Take the example above concerning e-mails. If I always had to have previous evidence that Jeff exists before accepting any e-mail as being from Jeff, the correspondence couldn't get started. I would be justified in dismissing the first e-mail as possibly being from a spam-bot or being a hallucination because I was previously a "Jeff agnostic" or "Jeff skeptic" and didn't know about Jeff's existence. Jeff's revelation of himself to me could never get off the ground.
Third, this argument confuses the direction a piece of evidence points with the conclusion one draws. I realize that this is a slightly technical point, but let me try to make it clear by examples. Suppose that I have a very negative view, based on previous evidence, of Joe's character. I've decided that Joe is just manipulative and utterly self-serving. Then along comes my shrewd friend Bill who tells me a credible-sounding story of Joe's behaving with apparent altruism within Bill's own knowledge.
Perhaps I do not conclude either that I've been wrong about Joe or that Joe has reformed. Perhaps I remain skeptical. Perhaps I hold open the possibility that Bill has been duped by a clever plan of Joe's to make himself look good. However, if Bill gives me a sufficiently detailed account of an apparently purely altruistic act, that is some evidence that points in the direction of Joe's good character. I may reasonably hold out for more evidence before changing my mind (because I did have evidence before of Joe's bad character), but my probability concerning the proposition, "Joe is right now simply a self-serving jerk" should, rationally, shift because of the evidence that Bill brings.
It's important not to think that a piece of evidence must do all the work on its own, that it must be enough to make a skeptic conclude that God exists or to draw some other conclusion against which he previously believed himself to have some evidence, in order to realize that the evidence points away from the skeptic's previous position and should cause the skeptic's probabilities to change. That is the point of a cumulative case. Different arguments and pieces of evidence do their work, and the reasonable skeptic can change his mind gradually as a result of the accumulated evidence coming in. Therefore, to say that a skeptic will not conclude that God exists from a report of a miracle should not be taken to mean that the report does not point in the direction of God's existence and that it should have no impact upon the skeptic.
Fourth and perhaps most importantly, this argument conflates what a skeptic will or might do with what a skeptic may rationally do. The former is psychology and sociology. The latter is epistemology. We mustn't conflate the two. It may well be true that a particular skeptic "would not be persuaded though one should rise from the dead." It may well be true that such a skeptic will adopt any wild, ad hoc theory rather than believe that a miracle has taken place. But this is a statement about that skeptic's psychology, not about what is rational. Is he rational to be willing to believe anything, including a lot of independent people's mass hallucination, rather than believe that a miracle has taken place? No. That would be a desperate theory rescue for his own naturalism, and we shouldn't imply that it is anything better.
In fact, there are plenty of objections--good, bad, and ugly--that have been raised against various metaphysical arguments for God's existence. If we are just talking about what a skeptic will do or might do, it could just as easily be predicted that he will bring up this or that objection and reject those arguments as well! Why not? If we're willing to postulate a skeptic so stubborn and determined that he'd rather believe that he and everyone else is hallucinating rather than believe that a miracle has happened, he can easily, in fact probably more easily, come up with some "reason" to reject all of Aquinas's Five Ways!
But if we are talking about what is rational, if we are doing epistemology rather than psychology and sociology, then we should recognize that detailed, credible evidence of miracles does support the existence of God and that a skeptic who will do anything rather than take such evidence seriously is being irrational.
It would be difficult to over-stress the importance of this last point. It is simply facile to say or even to imply that, if an atheist will or could reject an argument for Christianity that one doesn't favor (or that one thinks needs to be kept in its place, meaning subordinate to or subsequent to one's own favored arguments), this means the argument is no good. Everyone can play at that game. I can pick any argument for God's existence or for Christianity and drum up an extremely plausible scenario in which an atheist dismisses it stubbornly. But if he's being unreasonable to do so, that's the important point for the epistemology of religion. Arguments can never overcome the human will to disbelieve if that will is strong enough. Man can use his free will to warp and confuse his own mind, to dismiss things that shouldn't be dismissed. That is a sign of the will to evil, the fall of mankind, sin nature. It isn't a defect in the arguments.
It should be obvious that a person who would rather believe that he is hallucinating all the reports than believe that there is some evidence that Jesus rose from the dead is being unreasonable. It is no help to the cause of Christ to bring up such wild scenarios, point out that a skeptic could adopt them, and then use that as a club against the argument from miracles.
Finally, one more small epistemological point: If the argument from miracles has no independent force, it doesn't magically acquire it for a person who already believes that God exists. This is extremely confused. It isn't possible to deny all independent force to the argument from miracles and then to try to revive its force for the person who is already a theist. This would be like saying that an e-mail that appears to be from my friend Jeff has no force in favor of his existence if I don't already believe that he exists on some non-e-mail basis and then to turn around and say that, voila, it really has some kind of unspecified epistemic value for me once I already believe in his existence. Epistemology doesn't work that way. Be careful: If you work hard to argue that an argument is forceless when you don't want it, you can't expect to whistle the argument up later like an obedient dog when you do want it.
Consider: The Jews believed that they had independent evidence that Jesus could not be who He said He was. Why weren't they justified, despite (and in a sense because of) their Judaic theism, in believing that they were hallucinating the reports of Jesus' resurrection rather than conclude that they had been wrong and that Jesus really was the Son of God? Why not? What is sauce for the atheist goose is sauce for the 1st century Jewish gander. If we're going to place all the weight on one's independent, prior probabilities and "diss" the argument from miracles, then it is arbitrary to say that the evidence for a miracle should rationally overcome one's prejudice in favor of a contrary religious presupposition but cannot possibly rationally tell against a person's contrary irreligious presupposition.
As I have said many times before, evidence is evidence. Take it or leave it. Don't try to make it dance to your own tune.