With a discrete random variable, you can count the values. You can list the values. Let's do another example. Let's let random variable Z be the number of ants born tomorrow in the universe. Now, you're probably arguing that there aren't ants on other planets, or maybe they're ant-like creatures, but they're not going to be ants as we define them, but how do we know? The number of ants born in the universe, maybe some ants have figured out interstellar travel of some kind. The number of ants born tomorrow in the universe, that's my random variable Z.