We had that “but you can’t prove it” discussion at our beer bash at work the other day. The one where your co-debater suggests that, if you believe something without proof, you are making a leap of faith.

Consider the proposition,

The cow jumped over the moon.

Those who consider the proposition true have no proof. But, according to the faith=belief without proof people, neither do those who consider it false. Both positions require faith because there is no proof either way.

The only rational position, according to the F=BWPs, is to say

“I don’t know whether the cow jumped over the moon”.

Yet everything I know about cows and moons and gravity suggests that it’s extremely unlikely that a cow jumped over the moon. The only evidence that it happened at all comes from an ancient nursery rhyme. One by one, the ancient nursery rhymes have turned out to be made up and I am certain that this one is too.

[At this point, I am obliged to acknowledge that some people believe in transcendental cows that don’t interact with the world as we know it and that ‘moon’ could be a metaphor for very small flowers or for the laughter of children]

Where the F=BWEs trip up, I believe, is in mistaking the standard of mathematical proof for the everyday standard of proof which is closer to the legal, beyond a reasonable doubt. Even in science, there is very little that can be proved to the mathematical standard.

Stanley Fish, in the New York Times (non-firewalled version), has a more sophisticated version of F=BWE theory:

I believe in evolution, Dawkins declares, because the evidence supports it; but the evidence is evidence only because he is seeing with Darwin-directed eyes. The evidence at once supports his faith and is evidence by virtue of it. Dawkins voices distress at an imagined opponent who can’t see the evidence or refuses to look at it because it contradicts his holy book, but he has his own holy book of whose truth he has been persuaded, and it is within its light that he proceeds and looks forward in hope (his word) to a future stage of enlightenment he does not now experience but of which he is fully confident.

PZ Myers at Pharyngula, in Fish has faith; I have confidence based on evidence, says

Fish is playing word games, using an imprecision in the English language to tag disparate phenomena with the same label. He can claim that the “faith” of the scientist is the same as the faith of the pious only because he does not understand the former. Accepting religious faith is to stand still and imagine a journey through a fantasy land, while science is about walking forward on firm footing towards a destination to which we may not have arrived yet, but can see glimmering on the horizon. It simply doesn’t matter that the faith-head is using his reason and imagination to extrapolate and create his fantasy world, so exclaiming that he has a brain and is using it doesn’t rescue him. The scientist will discover something new Fish considers that remarkable and a strong assertion, and unsupported by evidence, but it’s a commonplace consequence of using science and ignoring religion but that isn’t a matter of “faith” at all. It’s about as remarkable as understanding that the sun will rise in the morning.