As the philosophy professor looked out over his 8:00 am class he noticed that half of them were sound asleep, and the remaining students were struggling to keep their eyes open. Near the back of the class sat Betty, bright eyed and bushy tailed, eagerly taking notes.

After class, the professor stopped Betty and asked, "Betty, why is it that half way through my lecture I notice that most of the students are sleeping, but there you are wide awake rapidly writing notes."

Betty replied, "Well, sir, the night before our class, I remove my contacs,and place them in the fridge. The next morning I put them on before class."