James D. Macdonald said:
That's the secret of building alien/fantasy worlds too: Don't explain: Show.
There's one important caveat to this I feel compelled to add to this, though it may have been addressed already in this thread, but I am still catching up on the first hundred-odd pages.
You, the writer, must have everything explained to the reader's satisfaction. Just don't put the explanation in the story.
What does that mean? I mean you have all the details worked out somewhere - on paper, in your head, whatever - and the actions you are showing all fit within that model of reality. All writers must do this, but it is particularly important for SF&F because you are creating the world from scratch.
"I got in my car and headed for Long Island" is a good example of this, but think about all the things both you and the reader know about this. Now pretend your reader is living 150 years ago. Presumably you've already established that this "car" is essentially a horseless carriage that runs on distillates of petroleum, and it is not uncommon for people to travel at 70 miles per hour. So the reader of 1855 says a-ha! Since it is 35 miles from City Hall in Manhattan to the city of Babylon, Long Island, the trip will only take half an hour!
Well, no. At this point you might feel compelled to explain that it will take some time to get out of the city, or at least onto the highway, due to lights and traffic and so forth, and in fact it will take somewhat longer than an hour under the best circumstances.
But instead of explaining, you should do what would work for a modern reader: show the protagonist waiting in his car at a light that takes a good five minutes before he can turn onto Houston Street; show his frustration with the accident stopping traffic on FDR drive. And there's no need to justify the time it takes with a detailed route and velocity-time profile. You have it worked out, so it is simply what happens.
This is a real-world example, but it's the same for a future, alien or fantasy world. In this example you are working out the details consistent with a particular model of reality – the model you already have in your head of how early 21st century automobiles, cities and roads work. But that model didn't get there because somebody sat down and explained it all to you over an intense week-long seminar, it's there from experience. So when you're writing SF&F, you first need to construct a realistic model of how your imagined world works in your own head. Then your job is presenting readers with enough
experiences to reconstruct that same model themselves. Explain it and they'll forget and misunderstand. Show them, and keep showing them things that work according to the same equations and mental maps, and eventually they'll get it. It's more fun that way, too.
I suspect the first step is the reason many people feel compelled to start stories with the several-page explanation of the "how the Zylarks who had wisely ruled Nudsimia 500 years ago" variety. They instinctively know that they need to get this all worked out, so they write it down. That's good. I suppose what I'm trying to say here boils down to this:
don't ever skip this step. But, this is not the beginning of the ms. Take it and post it on the corkboard over your desk where you can refer back and refine it as needed. Now you can start writing about the things that happen in your story.
What I've said is focused on SF&F, but I suspect it is the same for all fiction writers. You can take shortcuts since contemporary readers already have their model of how the modern world works established. But you will at least have to establish characters and how they think and behave. And perhaps you will have to create a fictitious neighborhood in Des Moines, or get people's heads around the corporate culture at ABWidgetCo. And you might just want to adjust your readers' model of how the real world works while you're at it. That's what it's all about in the end, isn't it?
