Mmm. Twinkies. Wait, where were we? Oh, that's right. Number 2. Charlie tells us a story about rats, pleasurable rewards, and electric shock. It's a very interesting experiment if you can put the whole animal-testing thing aside.
What do we learn from this? "The rat or mouse would put up with a lot more voltage for the pleasure. Even more than for the food" (2.3.2). Pleasure trumps all.