And so you say, okay, there's four possibilities of one party. And if we assume people aren't shaking their own hands, which we are assuming, or they're always going to shake someone else's hand, then for the other party, there's only three other, for each of these four possibilities, who's this party, there's three possibilities, who's the other party. And so you might say that there's four times three handshakes. Since there's four times three, I guess you could say possible handshakes. And what I'd like you to do is think a little bit about whether this is right, whether there would actually be 12 handshakes. Well, you might have thought about it, and you might say, well, you know, this four times three, this would count, this is actually counting the permutations. This is counting how many ways can you permute four people into two buckets, the two buckets of handshakers, where you care about which bucket they are in, whether they're handshaker number one or handshaker number two.