Bill: I think we need more systems.
Nick: Systems? Why? What makes you say that?
Bill: Well, in the Other World...
Nick: Let me guess, they have a lot of systems?
Bill: Well, yes.
Nick: Is that a good thing?
Bill: I'm not quite sure...
Nick: Well, I guess that's why I'm here. What sort of systems did you have in mind?
Bill: I was thinking... money.
Bill: Yes. Money is a very important system in the Other World. Just about everything depends on it.
Nick: I'm intrigued! How does it work?
Bill: Well, say I wanted some food.
Nick: Don't you always?
Bill: Very funny, Nick.
Nick: I'm sorry. Go on?
Bill: Well, if I wanted this food from someone else, they wouldn't just give it to me.
Nick: I suppose. If they needed it, they would probably want something in return.
Bill: Right! Something that they want. Like maybe I have some extra water.
Nick: Okay, so you make a trade, and both of you get the things you want. That's not money, is it?
Bill: No, but I'm getting there. Now, say I didn't have any water to give, but I still wanted food.
Nick: You could give them something else that they wanted.
Bill: Only they don't want anything I have.
Nick: So you're stuck!
Bill: Right! Unless I can convince them they do want something I have.
Nick: How would you do that?
Bill: Well, I might tell them that I have some other goods to give them that they could trade with someone else to get water.
Nick: So you get food, they get water, and someone else gets what you started with. Sounds good to me! But I'm guessing this isn't money either?
Bill: Right. So, say I don't have anything they could trade someone else for water, either, because the person with water doesn't want it.
Nick: Then you could trade them something that they could trade to someone else that the someone else could trade to another person for something they want?
Bill: I could, but isn't that awfully complicated?
Nick: This is where money comes in, isn't it?
Bill: You bet! The idea of money is to find something everyone wants, so you can always trade it. So what does everyone want?
Nick: Food and water?
Bill: Not if they already have lots! It has to be something you can never have too much of.
Nick: Hm... But then you may not want to trade it?
Bill: Good thought! So it has to be something no one wants, but everyone wants.
Nick: I'm not sure I like this money idea, Bill. It seems sort of, I don't know, impossible.
Bill: Well, what you do is make something nobody wants into something everyone wants.
Nick: Like what?
Bill: Like slips of paper, or metals made into little shapes.
Nick: Really, Bill?
Bill: Yes! So then if you wanted food, you would give some slips of paper or pieces of metal to someone with food, and they would want them because they could trade them to someone else to get whatever they want!
Bill: We could call the metal pieces... "Coin" because they would make a noise kind of like that when you drop them, and call the paper slips... Well, they don't make a noise, but we could call them... "Bill", named after me, since I thought of it. Coins and bills!
Bill: And coin.
Bill: What's wrong, Nick?
Nick: Bill, for this to work, you would have to convince every single person to pretend they want those worthless things, or else the system would fall apart! There is no way you could get everyone to assign some sort of value to pieces of junk, and no one is going to want to trade for them if they can't trade them again to someone else.
Bill: Yes, but---
Nick: And how would you decide how much everything is worth in these 'bills' and 'coins'? Someone who has almost enough water wouldn't want to trade very many of them for a little more, but someone who just spend a week in the desert might be willing to give all of theirs! It's too hard to regulate!
Bill: Well, it works in the Other World... They love the stuff...
Nick: Bill, what have we learned about the Other World?
Bill: "Not everything I see in the Other World is a good idea."
Nick: Right, Bill. It was a good try, though.
Bill: Thanks, Nick...
Nick: No, really! It was much better than that silly castle idea. I think you're getting the hang of this.
Bill: Really? Well, I've got a few other ideas...