Teacher: "Which is more important to us, the sun or the moon?"
Pupil: "The moon."
Teacher: "Why?"
Pupil: "The moon gives us light at night when we need it but the sun gives us light only in the day time when we don't need it."
Patient: "What are the chances of my recovering doctor?"
Doctor: "One hundred percent. Medical records show that nine out of ten
people die of the disease you have. "Yours is the tenth case I've treated;
the others all died."