Secondary Worlds

JRR Tolkien coined the concept secondary worlds which in my opinion has made fantasy to what it is today.
A fantasy-story can tell a story that is impossible in this world, instead it takes place in a world that is impossible, but the story make sense according to that worlds frames of references.
Our world has certaiin laws that has to be followed (laws of physics, etc), the author has to invent a world of his own, but he also has to make up the laws for that world, what laws of nature there would be, if magic can exist, which creatures there can be and so on.
That's one of the reasons why fantasy is so complex, and a story often spans over several volumes.
The majority of all fantasy takes place in a secondary world.

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Calle Åsman [emsworth [at] gmx [dot] net]