So, where do you start?
There are many methods to start building your world, but one of the most important things about Worldbuilding, is Economy.
Economy!?
Yeah, Economy.
Most people, when they hear the word Economy, think money: the buying and selling of resources. But Economy is much more than monetary transactions, and in understanding that, we can then learn how to apply that to Worldbuilding.
Put simply, Economy teaches us that everything has a cost, but that cost is not always money. Let me demonstrate that for you.
I want you to give me cookies. Imagine all the ways you can supply me with cookies (provided we are in the same location, and you have the means to do it). The two main ways you could get me cookies is to either buy a package of them or make them. The question then becomes: how much does it cost for either option?
As an example, let’s say a package of cookies costs $5, and buying all the ingredients to make cookies, let's say $15 (I’m sure it’s more than that). But as we established, there are more costs than just monetary ones. For instance, we have to go to the store. We have to take a car to get there. A car uses gas, which adds to our cost. We can represent that in dollar amounts. But it is not just going to the store, it's also coming back. So we can estimate a gallon of gas (really far store) for whatever your local price is.
Then there is time. If you weren't buying me cookies, you could be doing something else worthwhile (or not). Time to drive to the store, time to find the cookies, time to buy them, time to drive back home. In the case of making cookies, that too is a factor of time. Furthermore, we have to use the oven, which requires energy.
As we can see, to get me cookies is not just a cost of your hard earn money, but one of time and energy.
Now that we have expanded our understanding of cost, let us discuss how this affects Worldbuilding.
Imagine a king in a medieval castle, and he is served chicken. Could be from a farm, or a wild chicken from the nearby forest. Before he eats, he picks up some salt to put on his chicken. Where did that salt come from? How is the king able to use salt with his meal?
What ways could the castle servants have obtained salt? Perhaps the salt is mined for. Look at that, suddenly our kingdom has a salt mine. Or, maybe they live near the coast, and use the ocean to get salt, which involves workers and processing. Suddenly you know more of the geography and some of the land’s inhabitants. Perhaps it is neither of those things, and they buy it from a merchant. Where did the merchant get it from? A neighboring country? Look at that, you've expanded the world.
Salt has to come from somewhere. Knowing where it originates helps you better understand your world. Now, this may just be a background detail that doesn't make it into your story. You don't need to write: “The king picks up salt, which was purchased from a merchant who got the salt from a neighboring country that they have an established trade with.”
Just say: “The king picked up salt.”
Let's give another example. Your soldiers go into battle with their swords. Where did the swords come from? Blacksmiths made them. What metals did the blacksmiths use? Maybe this story with soldiers in a battle takes place during the ancient age, and they use bronze swords. Bronze is a combination of copper and tin. Was this society fortunate enough to have both copper and tin mines? Or did they have one metal, and trade for the other? Have neither and traded for both?

Economy is the place you start when you build your world. You know what your characters will do. They’ll fight in a sword duel, or fly across the universe in a space ship. They will need to eat, and drink, and sleep. So the question becomes, not only how they do this, but how do they come to being able to do these things. When we can understand that, it reveals more about your world and makes your story more complete.
It is imperative to remember that things have a cost. If you want something to appear in your story, you need to understand where it came from and how it came into being. You need to take me to your world, and immerse me in it. I want to feel like I’m there. The more a writer knows about their fictional world, the more a reader can feel connected to the story.
Find Christopher D. Votey at his website and on Twitter.
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