Proteus in Greek mythology is a sea god who attended Poseidon. Proteus had the power of changing his own form or appearance at will. Hence, Proteus refers to a person who changes his appearance or principles with ease.
Protean: The adjectival form of Proteus is protean. Protean means of or like Proteus, someone very changeable, readily taking on different shapes and forms; something that can change quickly and easily, variable.
Michel Houellebecq, the French essayist, poet, and novelist, mentions Proteus in his novel Submission: “So it goes, in the remaining Western social democracies, when you finish your studies, but most students don’t notice right away because they’re hypnotised by the desire for money or, if they’re more primitive, the desire for consumer goods (though these cases of acute product-addiction are unusual: the mature, thoughtful majority develop a fascination with that ‘tireless Proteus’, money itself). Above all they’re hypnotised by the desire to make their mark, to carve out an enviable social position in a world that they believe and indeed hope will be competitive, galvanised as they are by the worship of fleeting icons: athletes, fashion or Web designers, film stars and models.”
Proteus is sea-god, or god of rivers or oceans. Homer refers to him as the Old Man of the Sea (The Old Man and The Sea is one of Ernest Hemingway’s famous novels). His name also figuratively refers to change, elusive sea change, constant changing nature of the sea; versatility, mutability, for he could assume many forms. There is also a ring of positive connotation when something or someone is referred as protean, and also to a person who changes his or her principles.