One day a professor was discussing a particularly complicated concept with his pre-med students. A student rudely interrupted to ask, "Why do we have to learn this pointless information?"
"To save lives," the professor responded quickly, and continued the lecture.
A few minutes later, the same student spoke up again. "So how does physics save lives?" he persisted.
"It keeps the ignoramuses like you out of medical school," replied the professor.
this one ALWAYS makes me laugh. :D