Homer: Okay. Okay, think back to your training! (he thinks)
Trainer: Now, Homer, this may very well save your life one-day. This... Homer?
(We see Homer is playing with a Rubik's cube.)
Homer: Yeah?
Trainer: Please, pay attention. This button here controls the emergency override circuit. In the event of a meltdown, push this button and only this button.
Homer: Ooh, a side!
Trainer: Simpson!
Homer: What?
Trainer: You see which button I'm pushing?
Homer: Yeah, yeah, yeah. Push the button. Got it. Stupid cube, this is all your fault.