A Bayesian and a frequentist are out for a drive...

Photo by Cary Wolinsky

A Bayesian and a frequentist are out for a springtime drive in the country. The Bayesian notices a flock of sheep on the hillside, and says, "Look, the sheep have been shorn." The frequentist replies: "Well, on the sides facing us!"

[Meaning: The Bayesian is using prior knowledge to infer that the sides of the sheep away from the viewer have also been shorn, but the frequentist refuses to use prior knowledge.]