19 July 2005

Precise nonsense


An alert reader sends this article which reports that an Oxford professor of religion has calculated that "It is 97 per cent certain that God raised Jesus Christ from the dead — based on sheer logic and mathematics, not faith..."

This is a great example of the misuse of seemingly precise mathematical reasoning on nebulous premises to arrive at absurd conclusions, which are nevertheless taken seriously because they've been "mathematically proven". Let's have a look at the argument, shall we?
This conclusion was reached after a complex series of calculations. In simplified terms, it began with a single proposition: the probability was one in two that God exists.

Next, if God exists, the probability was one in two that he became incarnate. Further, there was a one in 10 probability that the gospels would report the life and resurrection of Jesus in the form they do.

Finally, the clincher: the probability that we would have all this evidence if it wasn't true was one in 1000.
Oh, where to start? First up, the probability of the existence of God. I assume the "reasoning" went something like this: either God exists, or not. Two possibilities, therefore the odds are 1 in 2.

Um, no. Either the world will make a quantum leap to an orbit around Alpha Centauri tomorrow, or it won't. Are the odds of this therefore 1 in 2? If you think they are, I want to make some bets with you.

In fact, the only evidence for the existence of God is that most people really want it to be true. The lack of evidence doesn't make it false — rather, the problem is that there's no way to prove or disprove the proposition, no way to settle the argument.

The odds of incarnation seemed to have been arrived at the same way. Any other calculation would have involved knowledge of the, by definition, unknowable. I can't imagine how the one in ten figure for the gospels was arrived at — I think it was invented out of whole cloth. The same for the 1 in 1000 figure for having writings about something that isn't true. (Imagine a future archaeologist coming upon all the writings on MiddleEarth — should he assume it really existed?)

Using these absurd inputs, we get 50% God exists x 50% incarnation x 10% gospels = 2.5% percent all of that happened. Multiply that by 99.9% (since we have so much "evidence"), and we get 2.4975% chance that God exists and became incarnate and the gospels recorded the truth and the preponderance of the "evidence" reflects reality. If the article is reporting the "odds" correctly, the headline is backwards — it's 97% likely that God did not raise Christ from the dead.

If you're going to make an argument this stupid, you should at least get your math straight.

The truth value of the resurrection is a matter of belief, not knowledge; mythos, not logos. Trying to drag it into the realm of the rational debases both reason and belief.