DS6's most recent line of logic:
Background: We're in the van, driving home from daycare. We having been talking about something completely separate from the following conversation:
DS: Mom, you know there's no vampires on this Earth, right?
Me: Yeah, how do you know that?
DS: It's easy. See, if there was a vampire he would have to bite a person and that person would become a vampire. Then there would be two vampires and they would both have to bite people so then there would be 4, and then they bite people and there's 8, and then 16, see...?
DS: Well, pretty soon if all the vampires keep biting people like that then everyone would be a vampire. And since you're not a vampire and I'm not a vampire then that means not everyone's a vampire so that must mean that no one's a vampire.
This is the kind of weird conversation that I don't think is happening in the vehicle next to me at the stop light.