I have watched different versions the movie and read the book a number of times, and I still can't decide: Was Deckard a replicant?
I know that he has an emotional reaction to the question of how he feels about killing androids while attached to a Voigt-Kampff machine, but I feel the book is ambiguous about whether or not the Voigt-Kampff tests are even accurate.
My question is: In the original Phillip K. Dick story, were we supposed to believe that Deckard was a replicant?
I believe that the title, while seemingly sort of silly, is a stand in for the real question. Could an android ever experience dreams and emotions the way we do? If they did, what would that mean? Would they really be any different than us? Aren't we just biological machines, a complex chemical reaction, fundamentally no different from a mechanical machine with electric impulses? Dick blurs the line further by making the replicants partially organic.
I think you're supposed to struggle with those questions and believe whatever you want to believe at the end. I doubt Dick even had an opinion on whether Deckard was a replicant.
Philip K. Dick stated in an interview (see 1) that Dick created Deckard as a human character who is gradually dehumanized through his violence towards replicants.
"The purpose of this story as I saw it was that in his job of hunting and killing these replicants, Deckard becomes progressively dehumanized. At the same time, the replicants are being perceived as becoming more human. Finally, Deckard must question what he is doing, and really what is the essential difference between him and them? And, to take it one step further, who is he if there is no real difference?
In the book, we learn that replicants are becoming more human. This juxtaposition of the arcs of technology and humanity is one of the compelling subtexts which makes the book a modern classic in my opinion.
I haven't read the K. W. Jeter sequels, but I assume this question would be addressed in them. If we're only talking about Dick's novel, though, I don't believe there is an answer. It's deliberately ambiguous to illustrate the lack of distinction between Android and Human. I don't think Dick wanted us to walk away wondering "Was Deckard an android or a human?", but rather "Can we ever really distinguish between the two?" He simply uses Deckard as an example. I don't know about you, but I was emotional about him killing the androids. Does that make me a replicant?
I thought the Dick novel was absolutely clear that Deckard was not an android.
No android in the book shows any sign of empathy, but Deckard does; the androids hate and mock Mercerism (the religion of empathy with the persecuted Mercer) - but Deckard is capable of empathizing with Mercer.
Some humans in the novel seem to have lost their empathy and become no better than the androids (and the androids work to encourage this), but none of the androids show any sign of growth in the novel.
The movie of course reverses all this (both the novel and the movie ask what the difference is between android and human, but in the book the question is "Can humans become as bad as androids?" (Yes), while in the movie the question is "Can androids become as good as (some) humans? (also yes).
I believe that Rick Deckard is an android. At the alternate police station, while he and Garland are waiting for the other bounty hunter, Resch, to get back with testing equipment, Garland tells Rick that Resch is an android. Resch returns and kills Garland, and the following exchange takes place:
"What did it say to you while I was gone?"
"That he--it--was an android. And you--" Rick broke off, the conduits of his brain humming, calculating, and selecting; he altered what he had started to say. "--would detect it," he finished. "In a few more minutes."
Later, when Rick tests Resch, the reader is not told the result. Rick continues to believe that he himself is human; however, neurons don't hum. They have pathways, not conduits. Moreover, the novel never establishes any difference between androids and human beings. What it does do is confirm the truth of Buddhism, which is that the ego, the "I" does not have an independent objective existence, but is dependent upon something which is its own cause.
"Do Androids Dream" is like the Anatma Lakshana Sutra turned into a paperback detective novel. The title of the sutra means "Discourse on the Characteristics of That Which is Not Self." Thus we learn that form, feelings, relative knowledge, subconsciously willing things to happen, and the resultant awareness of thoughts, are not what makes up Self, or God, although none of these things would exist without Self. Dick even gives androids intuition, an attribute of Self. Therefore, Philip Dick appears to be attempting (crudely) to say that humans believe themselves to possess attributes that the entities they build can never possess--some of which are ego and some of which are Self. However, the five attributes of ego are impermanent and changing, and therefore do not exist in humans or their creations, while the attributes of Self are permanent and immutable in both humans and their creations. And this is because that which creates a human being also creates whatever the human imagines it creates.
"Mahamati, it is like Pisaca, who by means of his magic makes a corpse or a machine-man dance with life though it has no power of its own: the ignorant cling to the non-existent, imagining it to have the power of movement." The Lankavatara Sutra
