The Proteus Problem

In Greek mythology, the “Old Man of the Sea,” whose name was “Proteus,” was assigned the duty of guarding a large herd of seals, the property of the god “Poseidon.” At noon each day Proteus would appear out of the sea and take his place on the rocks, with the seals gathered around him. Among his many talents, Proteus had the ability to look into the future and speak only the truth. But if someone wanted to learn something from Proteus, a problem in communication arose. It seems that Proteus was a “shape-shifter.” This meant that he could take any shape he wished. When someone asked him a question, he would avoid answering by reshaping himself into a tree or a lion or a dragon or water or fire, and so on. This frightened or discouraged most people. But if a person persisted, and really held on tightly to Proteus, the “Old Man of the Sea” eventually would answer the question, regardless of the shape…