One day Dr. Joseph Bell (Sir Arthur Conan Doyle's medical school mentor and the inspiration behind Sherlock Holmes) assembled a group of students around a patient's bed to demonstrate the deductive method of diagnosis.
"Aren't you a bandsman?" he asked the sick man. Yes, the man politely nodded. "You see, gentlemen, I am right," Bell continued. "It is quite simple. This man has a paralysis of the cheek muscles, the result of too much blowing at wind instruments. We need only inquire to confirm. What instrument do you play, my man?" The patient's reply? "The big drum, Doctor."
[More often than not, Bell was correct. He first impressed 18-year-old Arthur Conan Doyle by correctly deducing that a patient was a left-handed cobbler: "Notice," he explained, "the worn places in the corduroy breeches, where a cobbler rests his lapstone." Bell later wrote the preface to Doyle's first mystery, A Study In Scarlet.]