1: Bayes Theorem is a time-tested way to use probabilities to solve complex problems. Bayes Theorem is the handiwork of an 18th-century minister and statistician named Thomas Bayes, first released in a paper Bayes wrote entitled "An Essay Towards Solving a Problem in the Doctrine of Chances."  

2: There is some debate among economists on whether credit should also be given to another economist, Richard Price, who edited and corrected Bayes' paper in 1763, after his death in 1761.Another wrinkle on Bayes Theorem stems from a 1774 paper by French mathematician Pierre-Simon Laplace, who was apparently unaware of Bayes original thesis. Laplace formalized the Bayes concept and is now viewed by economists as the individual who should share the credit for developing what's known as the "Bayesian probability."

3: Historically, the Bayes Theorem has led to significant breakthroughs. The theorem was used to crack to infamous Nazi Enigma code in World War II. Alan Turing, a British mathematician, used Bayes Theorem to assess the translations culled from the Enigma encryption machine used to crack the German messaging code. Applying probability models, Turing and his staff were able to break down the almost infinite number of possible translations based on the messages that were most likely to be translatable, and ultimately crack the German Enigma code.

4: Interestingly, there is no known portrait of Bayes in existence, and nobody really knows what he looked like (there is a sketched image floating around the internet, but it's never been officially confirmed as the "real Bayes.") But exist he did, and his theory on conditional probability remains widely praised today by mathematicians, businesses and even poker players, all over the world.

5: What Is Bayes Theorem?