Dear Mr. Dawkins,
I have just watched a talk show program featuring you and noticed that you have made a grave mistake in your reasoning. You stated that the probability for the existence of god is somewhere between zero and one but must certainly be very low. This assumption contradicts the fact that there is no evidence that could either prove or disprove that a god exists. Therefore -- as it is a binary decision -- the correct probability is exactly 0.5 for each of the two events.