A college physics professor was explaining a particularly complicated concept to his class when he was rudely interupted by a pre-med student.
“Why do we have to learn this stuff?” one young man blurted out.
“To save lives,” the professor responded before continuing the lecture.
A few minutes later the student spoke up again.
“So how does physics save lives?”
The professor stared at the student for a long time without saying a word.
Finally the professor continued.
“Physics saves lives,” he said, “because it keeps certain people out of medical school.”