Great, I'd been trying to think of a quote from that show for this thread. Loved it.

Katara and Sokka's polar opposite reactions to the fortune teller both seem like good rationalist attitudes. Sokka's the sceptic in the quote. Katara corners her and asks her absolutely everything she can think of, just in case she's for real.

Sokka gets extra points for living in a world where magic undeniably exists, but still looking for rational explanations.

Though my other favourite quote from him when he fails to explain something is "Thats avatar stuff, that doesn't count" (The Swamp) Not sure if that counts as compartmentalising or him acknowledging a lack of necessary expertise in a given area.