At the vet...
Peter: We have to give Max half of this pill tonight. If he poops worm tonight, we give him the other half in a week. If he doesn't, we give it to him in a month.
Me: Boy, I hope he doesn't poop worms.
Peter: Me too. They can really be harmful for dogs.
Peter: And of course, our neighbors' dogs could get them from him.
Peter: They're probably bad for the environment.
Me: Yeah. Listen. That's true and all, but the only reason I don't want him to poop worms is because it would be really, really gross.