Simulacron-3

In the 1960's, before anyone had even conceived of the concept of virtual reality, before computers were even in main-stream thought, Daniel F. Galouye imagined the unimaginable. In doing so, he wrote one of the most influential science fiction books of the day, and one that continues to not only influence modern writers but continues to resonate with science fiction readers everywhere.
He conceived of a world that exists only virtually...one of the first stories about virtual reality. This is Matrix, decades before Matrix was conceived.
Douglas Hall is part of a team that builds an artificial environment to simulate reality.
This enables them to get public opinion polls without waiting for the opinions of people around them. But then something goes terribly wrong and his partners on the program start disappearing.
But is it a simulated disappearance, or is someone out to get them all? And what is the true nature of reality?
Stories based on Simulacron-3 have been adapted for both television and movies, and the book is considered a favorite of many of the masters of science fiction.

Daniel F. Galouye was a science fiction writer who wrote two extremely influential novels, Simulacron-3 and Dark Universe; both some of the earliest examples of popular sub-genres and themes in science fiction. > (nominated for a Hugo when it was originally published) is one of the earliest (and many consider it one of the finest) examples of a post-apocalyptic novel. >, published in 1964, is one of the first to deal with virtual-reality. At a time when most of us had not thought of the concept, Galouye was writing a story about people realizing that they are virtual constructs in a simulation. In many ways Galouye was very much ahead of his time, even the science fiction field, and many science fiction writers credit him as being one of the great science fiction writers of the time. Daniel Galouye died at the age of 56 in 1976 due to poor health which was complicated by injuries he had received during World War II as a Navy pilot.