When I was a lot younger, I decided that one of my favourite science fiction themes was the one where “everything is not as it seems”. The neighbour is an alien, there's a tunnel under the world, our world is actually a construct, etc.
Then I realised that Philip K Dick was the master of that sub-genre.
Hand in hand with that, goes PARANOIA. Everyone's out to get you.
Yes, folks, PK Dick was a sadly paranoid person, not usually a high-class writer, and responsible for a body of the most highly imaginative sf ideas. A riffle through his five-volume set of short stories will cement these views. Some of the stories are quite directly about paranoia. Try Shell Game and Null-O (both 1953) for two very different takes on it, which ably demonstrate that he was at it from an early age.
So, funny isn't it, that his is the most fertile science fiction brain that's ever been picked by Hollywood. Do Androids Dream Of Electric Sheep? [Bladerunner]; We Can Remember It For You Wholesale [Total Recall]; Paycheck; Second Variety [Screamers]; Minority Report, A Scanner Darkly...
And now, The Golden Man, upcoming as Next.
A strong theme running through much of Hollywood's exploitation of Dick is that they tend to take the germinal idea, and completely rewrite it. Next is no exception. In fact, the original protagonist (who can see the future) was a mutant to be feared, not a Nicholas Cage-type action hero. And so it goes. It's not going to stop me seeing the film; nothing is.
Funny enough, but one of his works that is most overlooked, The Man In The High Castle, is the one that won him the Hugo Award – SF equivalent of an Oscar - in 1963. It's an alternative reality where the Axis powers won the second world war, and for some reason it is quite rare in bookshops and libraries. Worth hunting down.
A man of ideas. Which is, after all, what distinguishes science fiction most strongly.