MUDD: I lied.
KIRK: He lied. Everything Harry tells you is a lie. Remember that. Everything Harry tells you is a lie.
MUDD: Listen to this carefully, Norman. I am lying.
NORMAN: You say you are lying, but if everything you say is a lie then you are telling the truth, but you cannot tell the truth because everything you say is a lie. You lie. You tell the truth. But you cannot for. Illogical! Illogical! Please explain.
(Smoke comes out of Norman's head.)
NORMAN: You are human. Only humans can explain their behaviour. Please explain.
KIRK: I am not programmed to respond in that area.
(Norman goes blank.)
SPOCK: I believe they are all immobilised, Captain.