Homer: Aw, twenty dollars...I wanted a peanut!
Homer's brain: Twenty dollars can buy many peanuts!
Homer: Explain how.
Homer's brain: Money can be exchanged for goods and services.

Bart: The guys who wrote this cartoon don't know squat. Itchy should have tied Scratchy's tongue with a taut-line hitch, not a sheet bend.
Lisa: Come on, Bart. Cartoons don't have to be 100% realistic.