Dewey: Dad, do I have to circle the whole thing? I can't find any more rocks.
Hal: Son, look, we might be in the desert, but we are still civilized people, and civilized people put up arbitrary boundaries that they will fight to the death to protect. I'm pretty sure we passed some nice-sized rocks when we turned into the camp.
Dewey: That's half a mile away!
Hal: Don't be silly. Two miles, easy.