Actually, it's pretty simple.
Research, and you will know
Even when writers are developing worlds that are all their own, chances are they're based on some part of this world here on Earth. The environment, culture, clothing, etc. will have "real" world equivalents. So if we want to make sure that the details of our world-building make sense, we read up on the places similar to ours, and then write from what we've learned.
Cindy Pon, author of the upcoming SILVER PHOENIX, did just that: "I did a lot of research while writing my novel--buying expensive and beautiful books on Chinese architecture, Chinese costumes, Chinese landscapes... It helped me to build a sense of the world and the setting, which i used for my Kingdom of Xia."
Naturally, fantasy writers will play with the things they've learned, and come up with new and magical twists on what they know... But research still gives a great foundation on which to build.
Experience can be adapted
It might seem as though few of a writer's life experiences would fit into a book about sorcerors or dragons or ghosts. But the great thing about experience is that it can be shaped and altered within a story, to keep the kernel of what we know while adapting it to those unusual situations. I'd say there are three main ways we do this (though these groupings are somewhat arbitrary):
1) Setting. If we've already been to a place our fantasy world is based on (or if our fantasy world is fairly contemporary), our memories can help us describe the sights, sounds, and smells of that world as vividly as if it were completely real. And even if we haven't, we can always draw on similar experiences. Ellen Jensen Abbott, author of WATERSMEET, acknowledges that "the scale of Watersmeet and Seldara (as the whole land is known) is much larger than the White Mountains" which she drew on for inspiration, but she was still able to make much use of her time there "collecting details about trees, forests, streams, mountains, and animals."
2) Quirks and anecdotes. Even in a fantasy world, characters are going to have habits and histories that define them as people. And authors often lift those sorts of details from their lives. Sometimes from themselves: Cindy Pon notes that she based her heroine's love of food and interest in Chinese brush art on her own characteristics. And sometimes from others: Saundra Mitchell, author of SHADOWED SUMMER, says, "I can tell you that my mother used to fry green peppers and onions in our kitchen when I was little, and she had a red scarf she wore to hold back her hair, and that's a rich and pleasant memory for me. No doubt, that's why Iris remembers her mother's red dress; that's why Daddy makes green peppers and onions for dinner."
3) Emotion. People are people, no matter what sort of fantastical events they're facing, and their feelings are going to be much like our own. We may not know what it's like to have our village burned down by an evil warlord, or our sister kidnapped by faeries, but we've all experienced some sort of loss in our lives. And those feelings will tell us how our characters should be feeling. Situations change, but the emotions stay much the same.
Carrie Ryan tells how she did this in her novel, THE FOREST OF HANDS AND TEETH: "There's a scene where Mary, the protag, questions what right she has to believe that her dreams can come true. I pulled a lot of her feelings from an email I once wrote to my fiance wondering what right I had to believe that my dream of ever publishing a book could come true. Whenever I read that scene it still hits home!"
Does it matter?
So, clearly writers of fantasy have many ways of drawing on what they know in their stories. But why should they? Isn't the point of fantasy to take readers beyond everyday experience, into something new and wonderful?
Well, yes, but also no. Try to imagine reading a book where every single thing that happened, and every way the characters responded, was completely different from your own experiences. I expect you'd find it pretty hard to relate to the characters' struggles and to care what happened to them. The things that are familiar--dare I say "real"--in fantasy are what allow us to enjoy the parts that are strange and mystical, to imagine ourselves into the story and forget for a while it's fiction.
Jackson Pearce, author of the upcoming AS YOU WISH, says she uses real life experiences "to make sure my story doesn't get TOO caught up in the magic/fantasy aspect. A character with wings or magic or superpowers is all well and good, but that character has to have some flawed, human elements (regardless of his magical "race") to make him a complex, 3D being." And as Michelle Zink, author of the upcoming PROPHECY OF THE SISTERS, puts it: "It's still easy - and important! - to weave real-world issues into fantasy so that modern teenagers can relate to the challenges of their fantastical counterparts. Striking a balance between the escapism that attracts so many readers to fantasy and the realism necessary to make the whole thing believable is the hardest - and most rewarding - part of all."
Writers among us: Perhaps you'd like to share stories of how you used what you know (whether from research or your experiences) in your writing?
And for everyone: How important do you think it is for authors of fantasy books to draw on the real world in their stories?
GIVE UP THE GHOST (a paranormal YA)