The short story “We Can Remember It For You Wholesale”  is written by legendary science fiction writer Philip K. Dick. It is the story of a man whose memories and mind are repeatedly garbled by a combination of governments and private corporations.
The protagonist of the story is Douglas Quail, who seems at first glance to be just an ordinary salaried employee living out his ordinary life, escaping from the plainness of it all by fantasizing about visiting Mars. The fantasies grow stronger and stronger until one day he visits a company called the Rekal Corporation, where they offer to implant false memories into minds in order to add the belief to Douglas's mind that he had in fact taken a trip to Mars.
Unfortunately, just before the memory replacement is about to begin, Douglas's subdued mind begins to recall that he actually had been sent to Mars by an international police force called Interplan to assassinate the leader of an underground rebellion movement on Mars. Naturally, Rekal is freaked out by this revelation, so they merely wake Douglas up and send him on his way without implanting the memory, eventually refunding his whole fee for the procedure. Unfortunately, this experience causes the original memory to slowly unseed itself and the tale turns into a story of how a man deals with two conflicting sets of memories.
This story deals with a number of interesting issues, mostly dealing with how an individual would respond to multiple conflicting memories. Would the person descend into confusion, or would the person try to integrate the memories into some sort of mutant worldview?
“…The confusion might bring on a psychotic interlude” (359) expresses the concern of ethical and psychological issues as the result from the ability to put into someone's mind the ability to remember things that did not happen, and these issues are the ones that the story revolves around.
Even more interesting is how companies would deal with this...