In part 1 of my World Building series, I talked about constructing a fantasy world from the Top-Down, starting with a million-mile view and zooming down to the continents, the countries, the cultures, economies, and so on. But this is only one method for creating a world...
My science fiction universe, Terran Shift, was simply too large to start at the top. The universe, after all, is quite a large place. Even limiting my current work to just our solar system gives me dozens of planetary bodies to design and populate. Expanding into other solar systems increases the workload exponentially. So when designing this universe I felt it was more logical to use a Bottom-Up design method.
I started with a handful of ideas, a few pivotal moments in our near future that give a good indication of where we as a species are going. Next I filled out the near future - a timeline for the next 500 years. Then I plotted how and when we would expand into the solar system and beyond. When designing from the Bottom-Up, you have to begin with your characters and the stories that change their lives, then move out from there to design their surroundings, countries, factions, planets, and so on. You end up molding your universe around the characters you created, essentially creating a network of supporting cultures and people to allow your plot to play out.
This method has some benefits. It's especially good for designing a science fiction universe that has a large scope. Even for a fantasy world, this method allows you to detach your thought process from the world itself and concentrate on the people and their stories. Perhaps you want to construct a fantasy world rich with political intrigue and characters. Designing the landscape of that world is not nearly as important as the people in it -- once you know the people and their motivations, you can tailor the landscape for the needs of the story. This method lets you create any plot you want and then construct the elements it requires to function as you get around to them. If nothing else, that means you can get into the story faster and worry about building the world around it later.
And that is one of the biggest drawbacks. I often find myself making references to things in one story and then contradicting it in another, both in the same universe. I'm talking about big glaring errors as well as subtle ones. For example, I have a story that starts on Mars, and the first draft took place about fifty years too early. The problem was that I didn't have anything definitive planned on Mars at that point -- just a few bullet points on my timeline, nothing more. I had to flesh out the world design for our colonies on Mars in order to see the best way to fix the errors I had made.
Solving problems like this could be done by switching perspective to Mars and designing that new world with the same Bottom-Up mentality. Or, you can adopt a hybrid approach...
In part 3, I'll discuss a hybrid of the Top-Down and Bottom-Up construction methods.