I was explaining “endangered” and “extinct” to Phineas. He suggested that “ghosts” were extinct, and I said “no, because ghosts never existed.”

He said they had, and I said there was no evidence.

Phineas: “What about tree werewolves?”
Me: “Those don’t exist either.”
P: “Yes they do.”
Me: “No, because there’s no evidence of them. So we can just assume they don’t exist because it doesn’t matter either way.”
P: “Tree werewolves live inside trees and they’re what makes the leaves fall off the trees.”
Me: “No… we pretty much understand what makes leaves fall off. It’s the changes in light and temperature that signal that winter is coming. You could put a tree inside a lab in the summertime and simulate autumn and its leaves would fall off…“
P: “That just proves tree werewolves. Because how else could it make sense for a tree’s leaves to fall off in the middle of summer?!”