Sunday, September 24, 2006

Miracles (or how not to communicate with rational mortals)

A few months ago, there was a post over at Thinking Christian about the historical accuracy of the Resurrection of Jesus. This got me thinking about the inferences involved in reaching the conclusion that the Resurrection probably happened.

Intuitively, the Resurrection is significant because it is a very unusual event. We have never observed any other resurrections, so scientifically, we can estimate the odds at being around 1 in 10 billion. Or perhaps it's less likely still.

It is this improbability which has to be compared with alternative improbabilities in assessing whether we should infer that the Resurrection happened. For example, would someone write a story saying that it happened if it never occurred? Would the story have been embarrassing to the early church that promulgated it? Well, suppose that we assign a mere 1% chance that the story was fabricated, and another 1% chance that the church would have told a story that was embarrassing. Let's throw in another 1% improbability factor, just for fun. That brings us to 1 in a million odds that the story would have been written if it weren't true.

No help there. The story only becomes plausible when we reach 1 in 10 billion odds. After canceling factors, there's still only a 1 in 10,000 chance that the story is true. A rational person must conclude that the event probably didn't happen.

This isn't proof that the Resurrection didn't occur. It may have. It's simply not rational to conclude that it did.

If you're a god, what is the point of demonstrating your power in an unambiguous way to just a few people, when the rest of the world would be irrational to conclude that the witnesses were telling the truth?

What we have discovered here is a trap set by our intuitions. We intuitively think that miracles (highly improbable one-time events) are an appropriate way for a god to verify his status as deity. This intuition is flawed because it only works if the believer fails to be rational. Instead, the god should demonstrate his power in repeatable, scientifically testable ways, so that rational people will have reason to conclude he is at least god-like in capability.

4 comments:

Ken Brown said...

doctor(logic),

Instead, the god should demonstrate his power in repeatable, scientifically testable ways, so that rational people will have reason to conclude he is at least god-like in capability.

A nice catch-22. If it's testable and repeatable, you’ll call it a natural law and say no god is necessary. If it’s not testable and repeatable, you say it’s too improbable to believe! The more miraculous the miracle, the less probable it is, and thus the less reason you have to believe it, no matter how much evidence it boasts. While the less miraculous the miracle, the less reason you have for concluding it is a miracle at all!

If this kind of calculating rationalism is our only means for judging truth, only a trivial God would be acceptable, and a trivial god is no god at all. This means your epistemology (whether you call this logical positivism or not) does rule out the supernatural by definition, and therefore cannot be used to judge the truth of the supernatural.

Doctor Logic said...

Ken,

You seem to making two claims. The first is about whether a god could be visible to a naturalist. The second is about what kinds of claims we ought to believe.

To the first point: are you saying that it would be impossible for God to show up as a scientifically testable entity with demonstrably ability to suspend what we believe to be physical laws?

Q from Star Trek does this all the time, and no rational character in the show fails to believe in his existence.

Likewise, if we ever met God in a physical way, no one would need to have faith in his existence. In fact, he might be able to demonstrate powers that establish that he could have created the universe. For example, he could move remote galaxies to spell out birthday wishes for the Pope, respond to questions from humans and tell them how to make new discoveries, tell us where to dig up Atlantis, locate missing persons, heal every cancer patient overnight, bring people back from the dead, etc. Miracles by any standard, and yet verifiable, especially if he does it on an ongoing basis.

At that point, you might be a lot more justified in taking on faith that God is eternal, fully omnipotent, fully omniscient, etc. A logical positivist would still reject these attributes because they are unverifiable in principle, but the positivist would have no doubt about the person to whom you are applying the attributes, nor his power over everything we know about the world.

To finish up on the first claim, what should we conclude about the goodness of this alien if he fails to stop a tsunami that kills a 200,000 people? Having faith in his goodness at that point would be truly irrational.


Okay, on to epistemology. You say:

The more miraculous the miracle, the less probable it is, and thus the less reason you have to believe it, no matter how much evidence it boasts.

This isn't true at all. A miracle can be highly improbable and still be believed if the evidence assures us that the alternatives are less likely.

Your alternative epistemology renders probability useless. If your slippers are moved from the armchair to the corner of the room, you ought to believe that pixies moved them and not your wife. The fact that the pixie theory is astronomically improbable is irrelevant to your epistemology.

However, you don't treat like as like. You don't believe the miracles of other cultures, and you don't believe that mundane events were caused by improbable explanations. So when will you apply probablity analysis, and when will you not?

Again, this has nothing to do with logical positivism. None of the claims I'm talking about are inherently unverifiable.

...a trivial god is no god at all.

What's trivial about a God who follows rules and acts in predictable ways? What's trivial about saving lives and acting materially?

I think you have a preconceived notion of what the supernatural means. Supernatural just means inexplicable. However, there's no reason why there might not be spiritual realities that are material in the sense that they exhibit regularities.

Indeed, I would think that the spirit world would just follow a radically different physics to the physical world, not simply be chaotic and unpredictable. Is spiritual reality (if it exists) a place that is immune from inference and rational inquiry?

This means your epistemology does rule out the supernatural by definition, and therefore cannot be used to judge the truth of the supernatural.

Again, this isn't true of probability analysis, nor of my personal philosophy.

Probability analysis says that the supernatural event could have happened, but it's so improbable that it would be irrational to conclude that it actually happened when there are more probable alternative explanations.

My personal philosophy also acknowledges that there might be supernatural events. However, my philosophy rejects that they would impart to us any knowledge, even if probability analysis showed they actually happened. If they did so, they would become naturalistic.

Ken Brown said...

doctor(logic),

are you saying that it would be impossible for God to show up as a scientifically testable entity…? Q from Star Trek does this all the time, and no rational character in the show fails to believe in his existence.

Quite the contrary, I am saying that your own description of probability would entail that the people in Star Trek couldn’t even believe in Q! After all, no matter how grand the miracle he performed, it would always be more probable that they were simply deluded.

The fact is, we don’t judge such events on their probability, we trust our senses and the integrity of the people around us. The probability that Q exists remains astronomical given the sum of human history (he never showed up before!); the characters simply reject the relevance of this improbability. They are right to do so.

You don't believe the miracles of other cultures, and you don't believe that mundane events were caused by improbable explanations. So when will you apply probability analysis, and when will you not?

…I think you have a preconceived notion of what the supernatural means. Supernatural just means inexplicable.


This is silly. Since I believe miracles are possible, I have no a priori reason to deny that they have occurred in other cultures, whether accomplished by my God or some other. You are the one insisting that supernatural can only mean inexplicable, implying that such events will always be less probable than any natural explanation (no matter how far fetched). The only way you are willing to admit that a supernatural event happened, is if it happens so consistently as to become natural! And you think I am the one with the preconceived notions?

Doctor Logic said...

Ken,

Quite the contrary, I am saying that your own description of probability would entail that the people in Star Trek couldn’t even believe in Q! After all, no matter how grand the miracle he performed, it would always be more probable that they were simply deluded.

I don't know why you would say this. Yes, one would certainly want to check that one wasn't deluded, but experimental repeatability resolves that problem. At some point, the weight of the new experimental data exceeds the weight of prior experimental data.

Of course, if Q does a trick just once and leaves no opportunity for us to accumulate supporting evidence, then we would be justified in arguing that Q was a delusion.

The probability that Q exists remains astronomical given the sum of human history (he never showed up before!); the characters simply reject the relevance of this improbability. They are right to do so.

If I win the lottery, I will find myself in a position in which I am observing something highly improbable. However, I do not accept that I won because I dispense with probability. I accept that I have won by my own definitions of what it is to win, and my observations of my bank account. There's no inconsistency between finding something you a priori believed to be highly improbable. Probability is perfectly capable of dealing with surprises.

Since I believe miracles are possible, I have no a priori reason to deny that they have occurred in other cultures, whether accomplished by my God or some other.

Do you believe all reported miracles, or just certain ones? And if you don't believe in all miracles, why not? On probability grounds?

The only way you are willing to admit that a supernatural event happened, is if it happens so consistently as to become natural!

I don't think you follow me. There's a difference between an unexplained event and an inexplicable one.

I believe in the unexplained, of course. If an event were explicable in principle, then it would be a natural event, in principle predictable from prior states.

However, for something to be supernatural, it has to be inexplicable. A claim to supernatural status is a claim not just that the event is unexplained, but that no search for explanation will never terminate. I think Gödel, Church and Turing dispelled that claim.

And you think I am the one with the preconceived notions?

Ken,

I think that there's a contradiction somewhere.

I'll try to put myself into your position.

God is neither random nor inexplicable in principle (e.g., to himself). God is material. Not physical, but material. That is, God's actions are logical, and in principle predictable, even if not predictable by us in practice.

In that case, there is no harm in rendering God visible through scientific means. Maybe not all of his actions will be predictable in the same way that not every event at the Large Hadron Collider is fully predictable. However, I fail to see why science threatens God.

Yet, when the issue of miracles somes up, discussion of science and rational consideration are abandoned. Probability is no longer deemed relevant. Instead, we are asked to rely exclusively on our intuition.