Philip K. Dick, 1978
An Interesting article by a Sci-fi writer on the nature of reality, mind, and fiction.
Here is a short excerpt...
It was always my hope, in writing novels and stories which asked the question "What is reality?", to someday get an answer. This was the hope of most of my readers, too. Years passed. I wrote over thirty novels and over a hundred stories, and still I could not figure out what was real. One day a girl college student in Canada asked me to define reality for her, for a paper she was writing for her philosophy class. She wanted a one-sentence answer. I thought about it and finally said, "Reality is that which, when you stop believing in it, doesn't go away." That's all I could come up with. That was back in 1972. Since then I haven't been able to define reality any more lucidly.
Here is another excerpt...
But I consider that the matter of defining what is real—that is a serious topic, even a vital topic. And in there somewhere is the other topic, the definition of the authentic human. Because the bombardment of pseudo-realities begins to produce inauthentic humans very quickly, spurious humans—as fake as the data pressing at them from all sides. My two topics are really one topic; they unite at this point. Fake realities will create fake humans. Or, fake humans will generate fake realities and then sell them to other humans, turning them, eventually, into forgeries of themselves. So we wind up with fake humans inventing fake realities and then peddling them to other fake humans. It is just a very large version of Disneyland. You can have the Pirate Ride or the Lincoln Simulacrum or Mr. Toad's Wild Ride—you can have all of them, but none is true.