than 200 years ago, the Reverend
Thomas Bayes described a general
solution for the computation of conditional probabilities in an
excellent article entitled "An
essay towards solving a problem in the doctrine of changes".
article was published after Bayes' death in 1763
in the Philosophical
Transactions of the Royal Society, London (53, 370-518).
method described by Bayes is of pivotal importance for the theory
of evaluation of diagnostic tests. The term "theorem"
is not really justified; in fact, Bayes' formula is a mathematical