A philosophical inquiry into arguments offered to defend advancing bad ends, deceiving, exploiting and despoiling, enforcing unjust laws, keeping confidences to the detriment of others or society and other seemingly wrongful actions by adversary professions such as law, business, and government. Applbaum (public policy, Harvard U.) finds that such justifications as rules of the game, fair play, consent, equilibrium, and institutional authority are weaker than most people assume.