I do think that Star Wars shouldn't be categorized in the same genre as classic science fiction but "can't be told in other settings" was a poor attempt at a definition. See my comment below.
I guess that depends which of the common definitions you subscribe to
I don't really subscribe to any one line definitions even though I tried to give one in my last post. To really understand the genre you would have to go to the book store and buy an anthology or two of classic science fiction stories (most are short stories) and just sit down and read. To try and distill a definition of the genre down to one or two lines is something that dictionary writers need to do but that doesn't mean they're accurate. I would say that's actually true for all literary genres. You can't understand what any genre, be it sci-fi, drama, western, horror, or anything really is unless you read it.
p.s. I don't mean to imply that I don't like Star Wars. It's actually one of my favorite movies.
For me Science Fiction means any narrative or story set in a world at a higher technological stage than us.
It's disappointing that the common definition of science fiction has degenerated so much. In classic science fiction the technology or science plays a central role in the story; it's not just part of the backdrop. If you can take the story and, without losing the central theme, re-write it in an alternate setting without the science and tech aspects then it's not real science fiction.
Philip K. Dick's 'Minorty Report' and Issac Asimov's 'I Robot' are good examples of classic science fiction. The story requires the technology. OTOH, Star Wars and most episodes of Star Trek (varies by series) are, imo, examples of stories which should not rightly be called science fiction since they could easily be rewritten in another setting and still retain the core themes and plot points.
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