Walking around my apartment with my keys in my hand.

The Brain: Let's put the keys down over here!

Me: But Brain, that's not their accustomed spot. We won't be able to find them again.

The Brain: Nonsense! I'll remember where they are.

Me: No, Brain. We should put the keys in their accustomed spot. That's the rule.

The Brain: Trust me, I know what I'm doing. (Brain puts keys down not in their accustomed spot.)

Fifteen minutes later.

Me: Yo Brain, I need to go out, where are the keys?

The Brain: The what now?

Me: The keys. I need my keys to go out.

The Brain: Well they must be in their accustomed spot.

Me: No, remember you put them somewhere else, right?

The Brain: That would be crazy. If the keys are not in their accustomed spot we won't be able to find them again.

Me: Scumbag BRAAAAAAAAAAAAAAAAIIIIIIIIIIIIN!!!!! You'll pay for this!!