Some first-year medical students were attending their first Anatomy class. They gathered around a table where a real dead body had been placed for study. The professor began the class by telling them that every good doctor must have two important qualities. “The first,” he said, “is that a doctor must never be disgusted by anything in the human body.” To demonstrate, he inserted his finger into the dead body’s anus, then put the same finger in his mouth and tasted it. He then asked the students to repeat what he had done. The students were shocked and hesitated for several minutes. But eventually, one by one, they did the same thing. Each of them inserted their fingers into the body’s anus and then tasted their fingers. When everyone had finished, they all stood there frowning and feeling uncomfortable. The professor then looked at them and smiled. “The second most important quality of a doctor,” he said, “is observation.” He continued, “I inserted my middle finger, but I tasted my index finger.” Moral lesson: Always pay attention and learn to observe carefully.