But the numbers will be easy to deal with just because, well, they're numbers. So let's say I have a set x. And it has the distinct objects in it, the number 3, the number 12, the number 5, and the number 13. That right there is a set. I could have another set. Let's call that set y. I didn't have to call it y. I could have called it a. I could have called it sal. I could have called it a bunch of different things, but I'll just call it y.