I had a really in-depth conversation recently that reminded me of a subject I'm always interested in passionately discussing: The dangers/merits of attempting to explain "How Fantasy Works" in a piece of fiction. I'm not talking about fan-theory, or even possible later explanations from the author, this idea is regarding the original source material. Things like the MASSIVE expanded universe of Star Wars may be considered canon, but to the person that hasn't read anything dealing with the expanded works, the movies are the be-all end-all.
One thing that is an almost universal issue for writers, whether they're writing a book, or writing out the dialog and storyline for a game, is the decision that has to be made with regard to how much you're going to explain any fantasy or sci-fi elements. There are a wide range of responses to this challenge, and ultimately the fans are the ones that decide if the world-building resonates. For the simplicity of discussion, let's imagine that there is a spectrum that ranges from absolutely no explanation on one end, to extremely detailed breakdowns of everything on the other. Somewhere on this range is contained the whole of the attempt to justify to readers things that are not proven to exist in the world(at the time of the writing!). Because it's going to get really wordy otherwise, I'm going to just group all the elements that are "made up" under the banner of fantasy.
One of the dangers of explaining is the same reason that Magicians don't generally show you the same trick over and over: You'll eventually see how it works, and it becomes another thing you can understand, and is therefore less magical.
I'll just take a stance on the issue and say that I think it's much easier to shoot yourself in the foot by attempting to explain your fantasy elements. One of the biggest outcries of the Star Wars prequels was the explanation that Force abilities were attributable to "midichlorians", which really diminished the mystical and mysterious nature that the Force originally held. One of the dangers of explaining is the same reason that Magicians don't generally show you the same trick over and over: You'll eventually see how it works, and it becomes another thing you can understand, and is therefore less magical. The mystery of the unknown is a boon for anyone who is attempting to build a fantasy for another person's mind to occupy. As an author you're trying to work with the reader to take them on a journey through fantastical elements, and part that requires finesse is taking either small liberties with reality, or to wholesale create one that in and of itself seems to have some plausible (even if left unexplained!) laws that govern it.
...And so you can see clearly that a Megatronic-Discombobulator would work in the atmosphere of Venus!
Dungeons and Dragons relies on an under-explanation model to the highest degree. Why are there Orcs? How do Magic Missiles exist? Why do physics only apply to selective elements of the game? You can spend all day asking questions like that, and nit-pik the fantasy to death. Over and over biologists have argued whether or not dragons would even be feasable at all as an organism. It doesn't really matter which camp you fall into on that issue: Dragons are cool, and a lot of fantasy worlds have them. Attempting to explain "how dragons exist" is unneeded at best, and is going to ruin the mood of any story-line that isn't already meant to be deeply rooted in the attempt to rationalize fantasy.
The "real world"* is a thing that exists for everyone. It's governed by shared set of physical laws, some of which we have at least a tenuous grasp on. If you follow science even casually you'll know that the sum total of things that we don't yet understand are practically limitless when compared to what we've sussed out so far. Science Fiction done well is often just the extension of currently available technologies extended into the theoretical future. "The Future" for Jules Verne isn't even futuristic to the modern age. In less than two centuries we've made such great advancements that many elements of the future envisioned by the Futurist movement is now anachronistic. We might not have jet-packs, but we've come a long way from vacuum-tube powered computers that take up entire rooms to play a game of Pong™.
There are exceptions all over the place. I know that. I love those even more for being the exception because in my opinion it takes a brave writer to attempt to delve deeply into the mechanics behind their fantasy. It takes a special level of confidence in your world-building ability to pull back the curtain and show the reader all the gears, because if you fail you'll never be able to gain back their suspension of disbelief. One author in particular I like to point to as a paragon of excellence in the field of explained fantasy is Patrick Rothsfuss. The magic used in the Kingkiller chronicles is so cool, and feels a lot like science. The masterful explanation of the way that magic follows a logical pattern in Rothsfuss' world was why I fell in love with his writing. His characters and prose are second to none, and the book is literally the first book I foist upon anyone who even seems like they might be looking to read something.
Who explains fantasy well, who catches your imagination, and what story do you think would have been better if it had been left less explained?
Off to read some books,
*Your definition of the real world may vary, live your life how you wish minion.