Reverend Thomas Bayes of Tunbridge Wells in Kent, England, was a Georgian gentleman scientist. These wealthy, independent, male citizens practiced science as a passionate hobby and not a profession. Many were priests. Church provided easy and respectable means of an ample income and vast spare time to indulge scientific queries. By most accounts, Bayes was a hopeless preacher, but an ingenious mathematician. At some point in his life, exactly when is not known, he devised a formula to work out various probability distributions of an uncertain event. And then; he forgot about it. Richard Price, Bayes’ friend, submitted this formula to Royal Society in 1763, two years after his death, under the title, 'An essay towards solving a problem in the doctrine of chances'.  Bayes’ theorem, as the formula came to be called, had no utility in Bayes’ lifetime. Today it is considered a landmark in the history of probability science and is used for: spam filtering, weather forecasting, DNA ...