"It goes up and down depending upon what is on each side. It is a relationship."
"It is like a comparison that makes what happens happen."
"You have to have two things and whether they are different or the same—in terms of weight here—makes the outcome what it is."
"The can crushes because of the greater air pressure on the outside than the inside of the can—that makes it a relational causality."
"You have to have some science knowledge to understand this one. The evaporating water leads to less air pressure inside than outside of the can."