I'm curious, and this isn't the kind of curiosity that can be satisfied solely be a poll. I want to know what the core elements of sci-fi and fantasy are. What makes them them, to you?

What needs to be in a sci-fi book, TV show, or movie, for it to be recognizable as sci-fi? Does there have to be advanced technology? Spaceships? Robots? New applications of current technology? Is there a mood or a writing style that's central to the genre?

Similarly, what needs to be in a fantasy for it to be a fantasy? Magic? Dragons? Medieval societies? Fairies? Swords? And again, is there a mood or a style that you associate with the genre?

My linguist training prevents me from giving my answers and ideas right off the bat. (They'll influence what you say. ) My ideas will probably come out in the comments, though. But no looking before you answer! That's cheating! :turbopoke; Once the conversations peter out, I'll probably post the results in an update. Probably.

Also, be warned that I'm going to play devil's advocate here, and point out exceptions to what you say wherever possible. Don't get mad at me; it's another linguist thing.*

* See, there's this whole thing about there being identifying "features" for every concept in a language, so that you can identify, say, a made-up animal as a bird or a dog or a fish, for instance. Like, birds have wings and beaks and lay eggs, but there's also (sort of) features for flying, singing, and nesting. I say sort of because not all birds fly, or sing, or have the same kind of nest. You can narrow the features down by constantly pointing out exceptions. I'm betting we're going to see the same thing here, where there are core features and then a bunch of "probablys".
tl;dr: I'm crazy and procrastinating.

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