Mathematical Digest

Short Summaries of Articles about Mathematics
in the Popular Press

"God's Number is Up," by Michael Shermer. Scientific American, July 2004, page46.

In the The Probability of God, author Stephen D. Unwin uses Bayes'Theorem and his "Divine Indicator Scale" to calculate the probability of God'sexistence. Unwin begins his calculations with a naive estimate of 1/2 for theprobability, and comes up with a probability of 2/3 that God exists. MichaelShermer, whose column is called "The Skeptic," also starts with 1/2 and usesBayes' Theorem, but assigns different values to the parameters in Unwin'sDivine Indicator Scale. Shermer determines that the probability of God'sexistence is 1/50. Shermer regards the calculations as little more than an"entertaining exercise in thinking," and concludes that "the question of God'sexistence is a scientifically insoluble one."

--- Mike Breen