A doctor of the insane asylum is examining three insane people. If they pass the test, the three will be released from the insane asylum, but if they fail, they will be detained for five years. The doctor took the three lunatics to an empty, waterless swimming pool and told them to jump. The first madman immediately jumped into it and broke his leg. The second lunatic also jumped into the pool as per the doctor's instructions and broke his arm. The third madman, however, did not agree to jump at all. The doctor exclaimed, ‘Hey, you did a great job! Go, you're free. But tell me one thing, why didn't you jump into the pool? ' The madman replied without hesitation, "Look, Doctor, I don't know how to swim at all!"