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In this scene from The Princess Bride, my favorite movie ever,Westley(The Dread Pirate Roberts) challenges Vizzini to a duel of wits.  In this duel Westley will poison one of without Vizzini knowing which of the cups is poisoned. Vizzini will then choose which cup each of them will drink.  As we see Vizzini spouts many arguments as to why Westley would or would not choose to poison one cup or the other. Finally, he believes he knows which cup is safe and drinks from it. Westley drinks form the other. Just as Vizzini is laughing and advising Westley to “never go against a Sicilian when death is on the line,” Vizzini drops dead. We can see though that each of Vizzini’s arguements are self-contradictatory as if Westley comes to the same conclusion, he would instead put the poison in the other cup. Systematic Actions can be thought through and defeated by the other player, therefore one must be unsystematic or random in order to win.

However the game being played is one of asymmetric information. Princess Buttercup was surprised to  find that Westley had put the poison in the cup he placed closer to himself. He replys with a tidbit of information that Vizzini would surely have liked to know, “They were both poisoned, I have been building up immunity to Iocaine for years.”  Vizzini didnot know that Westley’s payoffs differed from his and thus was not able to see him poisoning both cups.