Mental patients

Two mental patients were walking next to a swimming pool. One jumped into the pool and the other jumped in to save him. Their doctor saw the rescue and called the rescuer to his office. "Due to your actions, it appears your mental state is fine," the doctor said to the patient, "You can go home to your family, but before you do, you should know that the person you saved hung himself today." The patient replied, "He didn't hang himself, I hung him there to dry."