Truth-Inducement in Greek Myth

Although Achilles is fated to be the greatest warrior the Greeks had ever known, his mother tries to keep him out of the Trojan war by disguising him as a girl. Her plan is foiled only by Odysseus’ clever use of what we now call “game theory,” a sub-field of economics that often deals with truth-telling and truth-inducement. Odysseus pierces Achilles’ disguise by employing what is known as a “separating equilibrium.” Odysseus himself is recruited to fight at Troy only after a separating equilibrium establishes his own sanity. In game theory, separating equilibria can be used to induce truth. For example, assume that a person is either of type X or type Y. No one but this person initially knows his type and this person wants people to think he is of type X. If the individual is rational, asking him what his type is will provide no useful information. To achieve truth-inducement, one would have to create circumstances in which type X and type Y would act differently or have different characteristics. Separating equilibria, commonly taught in undergraduate economics courses, provide a unique and useful approach to studying truth-inducement in Greek myth.1 Such an econom-