Ragged Clown

It's just a shadow you're seeing that he's chasing…


Probabilities or Proof?

January
2007

Bob moved his blog and when I popped over to check it out, I saw that he had been continuing our discussion about Belief in Belief without me 🙁

From Bob’s comments,

Since there is no proof of the existence AND THERE IS NO PROOF OF THE NON-EXISTENCE of God or FSM, any position taken on the matter, other than agnosticism, is pure faith. Without proof that God does not exist, it is possible that God might actually exist.

– Bob

By a pleasant happenstance, I just read the chapter in Stephen Pinker’s How the Mind Works where he talks about scientific proofs and how inappropriate they are for everyday circumstances. According to Pinker, our ancestors on the savanna evolved sophisticated mental machinery for dealing with probabilities but formal proofs … not so much.

The number of domains outside of pure maths where proofs are appropriate, or even possible, is vanishingly small and only a logician would claim that belief in something improbable and disbelief in something improbable are in any way equivalent. Fortunately, most of the rest of us deal in probabilities and most of us would conclude that the possibility of an entity existing

  1. which violates many of the known laws of nature and
  2. for which there is absolutely no evidence

is so close to zero it is not worth considering.

Bob seems to be asserting that, given a proposition that is almost certainly false, the only reasonable position to take is to say “I don’t know” and that any other position requires an unreasonable leap of faith.


I cannot prove that I am not a brain in a vat. I cannot prove that you exist. I cannot prove that I existed this morning. I have no need to prove them. It would not be useful to prove them. The evidence to support those positions is overwhelming, reasonable and requires no leap of faith. The opposite positions – that I am a brain in a vat or that you do not exist or that I did not exist this morning – require an unreasonable leap of faith.

There is no god. I am certain of it.