Jonathan McCalmont's latest Futurismic column (Blasphemous Geometries) is online and entitled How to define a genre … and why not to bother...
Scientists have proved that 86.4% of all arguments in genre boil down to disagreements over what does and does not fit within a particular genre or subgenre.
Excellent stuff. Personally I definitely prefer saying "this is what I call Science Fiction" rather than the tick-list definition approach.
I quite like Theodore Sturgeon's definition myself:
"A science fiction story is a story built around human beings, with a human problem, and a human solution, which would not have happened at all without its scientific content"
But generally speaking I think arguing about genre definitions are pointless as is the habit of defining every sub-genre and sub-sub-genre.
Then again I'm the guy who likes to say sci-fi just because I know it annoys some people.
I do that sci-fi thing too :-)
"scientific content" is surely the contentious phrase? If something is made up, even if it is extrapolated, is it really scientific? Hmmmmm....