VALIS is a story of a man, named Philip (same as the author), and his journey to find God with his alter-ego, Horselover Fat. Most of the story is a narrative that disguises a set of theological ideals established by Dick. The major subject of this narrative is spirituality, as both the protagonist, his alter-ego, and the author (who are all essentially one and the same) are ostensibly obsessed with several religions and philosophies, including Christianity, Taoism, Gnosticism, and even Jungian psychoanalysis. They are searching for a cure for what he believes is simultaneously both a personal and a cosmic wound.
References on Lost
Locke picks out VALIS.
John Locke selected VALIS for Ben to read from his own bookshelf. Locke gave it to him while he was imprisoned in the basement of his own house in the Barracks. Upon receiving the book, Ben said flatly, "I've already read it." Locke responded sarcastically, "You might catch something you missed the second time around." ("Eggtown")
Ben is later shown reading the book in the cell. ("The Other Woman")
DHARMA Initiative telepathy experiment.
Both VALIS and Lost discuss the possible human ability to "mentally" travel through time, without the subject's body ever physically leaving. In the book, Horeselover Fat states that this is accomplished through "remembering" the past and the future. According to the book, this is achievable since all humans are born with a compilation of DNA from their ancestors, which also includes a compilation of their ancestor's memories. This being the case, time travel merely becomes the ability to access information regarding the past from one's own brain. This is similar to the mental time travel events Desmond experienced. ("The Constant")
A subliminal frame of the Room 23 video.
Cancer is a major theme in VALIS and Lost. Following his first love's spectacular suicide, Fat find himself desperate to aid Sherri, a woman whom he believes has willed herself to have cancer. The cancer's original cause, remission, and relapse - being either self-willed, acts of God, or medical anomalies - serve allegorically as a main query of the book. Also, Fat's pets both die of cancer, which he relates to the radiation caused by VALIS' communicating with him. Ben, Rose, Rachel (Juliet's sister), and Kate's mother Diane Janssen, all suffer from the disease in Lost.
VALIS discusses many scientific studies focusing on the brain, including telepathy. According to the Swan Orientation Film, parapsychology is one of the areas of study that the DHARMA Initiative was involved in. In particular, the film shows a woman participating in what appears to be a classic telepathy experiment. ("Orientation")
In the book, VALIS is the name of a movie that the protagonist, Philip, goes to see. In this movie, there are many easter eggs, subliminal messages, and hidden acronyms. Lost also uses these techniques in the show, such as the Room 23 brainwashing video. ("Not in Portland") Another Philip K. Dick story, Radio Free Albemuth, is considered to be a "rough draft" of VALIS. In it, VALIS instructs the protagonist to release subversive, anti-communist subliminal messages through a hit rock song.
The purple laser Daniel Faraday uses to shoot Eloise's consciousness forward in time has many similarities to the purple laser that gives Horselover Fat information about his son's illness. ("The Constant")