Two instances of the same class. If that class is restricted to have only one member (an "identity class"), then all instances will be copies of each other (where "member" refers to potential instances).
If it turns out it isn't. As far as I'm able to determine from slogging through the morass of JREF teleportation threads, those who have a problem with getting in the teleporter are arguing that consciousness is an active material process of a material instance of "a person", and that destroying that person destroys that process; those who don't have a problem are arguing that consciousness is the description of the material instance of "a person" and his or her active material processes (consciousness included), iow, the class or idea of this person, and this person's consciousness, which many think of and may be nothing more than the active material process, persists somehow in its static, symbolic description.
On one side, it seems to me, speaking philosophically, is an emergent materialism which identifies the process of consciousness with its separate material instance; on the other, a pythagorean idealism which identifies consciousness with its unique descriptive class. So whether you get in the teleporter or not depends on your metaphysics. (I incline to emergent materialism; though of all the idealisms, pythagorean is the most tempting: by far the least silly).
There is a third option:
My position is that human consciousness is a form of self referential information processing. It is an algorithm -- a series of computation steps -- that knows about itself.
My position is that the steps in the algorithm -- like any other algorithm -- can be thought of as a series of state transitions within the systems the algorithm is instantiated upon. Think about how programs are executed on a computer, how each step in a program represents a set of state transitions in the hardware. Well, my position is that the algorithm of consciousness is the same kind of thing in our brain -- the steps correspond to state transitions in our neural network.
My position is that these state transitions are deterministic, assuming quantum randomness is insignificant. This means the next state is determined by only the current internal state, the current external state, and a deterministic state transition function (which in the physical domain is simply the laws of physics).
My position, then, is that you can model consciousness (any algorithm, actually) as a series of state transitions in some system somewhere. That is, F(Si(t), Se(t), t) --> Si(t+1), where F( ) is the state transition function, Si( ) is the internal state, and Se( ) is the external state. If you looked at time slices of consciousness -- we can use plank time as the duration since then we know we captured any relevant events -- the algorithm would look something like this in the physical domain: S(1)-->S(2)-->S(3)--> ... -->S(current time).
My position is that consciousness is those deterministic transitions between states, the "--->" you see above. It is the algorithm itself, not the physical stuff the algorithm is running on. It isn't your brain, it is the directed "movement" from one state of your brain -- or any brain -- to the next.
My position is that if you take a subsequence of this algorithm -- suppose S(10)-->S(11)-->S(12) -- and split it between multiple systems, or instances, it remains the same algorithm precisely because the deterministic state transitions are exactly the same. In other words, if F(Si(10), Se(10), 10) occurs on system A, and determines state 11 on system B, and if F(Si(11), Se(11), 11) occurs on system B and determines state 12 on system C, the algorithm and hence the consciousness is exactly the same as it would be if everything occured in the same system.
So if your brain is in state 1, and the laws of physics combined with state 1 result in state 2 one planck time later, then the system where state 2 is located should be irrelevant. State 2 is still part of the algorithm, the same algorithm, because it was determined by state 1.
And finally, my position is that if you somehow add an intermediate step in there between determining state 2 and the system actually being set to state 2 -- such as communicating across space to an identical system that it should be set to state 2 -- the algorithm and hence the consciousness is still the same, because state 2 is still determined by state 1. The fact that there was a middleman doesn't change that key element. Nor would it change if that communication took a very, very long time -- if the original was scanned, then destroyed, and the information took a billion years to reach the destination, and only then was the copy made -- it would still be the same algorithm and hence the same consciousness. Because state 2 was determined by state 1
In other words, if your criteria for defining "instance" relies upon the deterministic transitions from one state of the system to the next then it is valid to say that the source and destination copies are the same instance -- since the source
determines the initial state of the destination.
Making, by these criteria, an instance of an algorithm identical with an algorithm (class); that is, the logical or conceptual description identical with the physical or material process it describes, which raises some prima facie objections. Such as:
If the material instance is the same as its descriptive class, then we shouldn't be able to distinguish between them. There should be no way to tell a material instance of consciousness from an equivalent description of that consciousness (that is, the logical relations, the potential instances, it describes; note every class describes potential instances; moreover, an identity class, because it is restricted to a unique potential instance,
is that potential instance). If an instance of the consciousness algorithm is identical to the consciousness algorithm as a descriptive class, then the potential instance of consciousness is identical to the actual instance.
Clearly, a person's consciousness is an actual instance of the class that describes it. Since the potential and actual instance are identical, there should be no way to tell them apart. If that's the case, then we should be able to do anything with a potential instance of a given consciousness that we can with an actual instance of a given consciousness: talk, picnic, go scuba-diving, get to know it better... spend some quality time with it. Yet we can't. Why not?
Maybe because the unique potential instance is not identical to an arbitrary material instance. Maybe the material embodiment, the particular material system where the consciousness is active, where the potential becomes actual, the class uniquely instantiated, shouldn't be taken for granted.
That's an excellent description of your position, btw. If I'm not mistaken (wouldn't be the first time), from a materialist pov, I think the obvious objection to it, as I've outlined in the reductio ad absurdum above, is its attempt at a matter-less account of consciousness.
So is your argument based on Parfit's -- as I understand it: that even though blobru#1's consciousness can't be transferred in the sense we normally think of someone's consciousness, that it should be enough for blobru#1 to be destroyed knowing an exact duplicate, his namesake, blobru#2, will carry on his legacy, in his stead ?
Yes. It's an argument about the Self, essentially. If you accept that materialism procludes the existence of a persisting self then you shouldn't have a reason not to travel. That's how I understand it.
I understand it as "if you expand your notion of 'self' to include your copies, then you shouldn't be bothered by the destruction of your particular 'self' (embodied consciousness)"; however, you may be right, I haven't looked at it in detail.
If I adopt an emergent materialist pov, the destruction (deactivation) of that separate active material process called consciousness that gave rise to the notion of "me".
Well, that's your own personal view. I also adopt an emergent materialist pov, but for me it's clear that there can be no difference between the illusory sense of experiencing self created by Nick#2 from that created by Nick#1!
Nick
Yes, it's certainly my own "personal" view.
I won't argue that.
I will argue that in emergent materialism the "self" (or consciousness or person or whatever) that emerges corresponds to a distinct active material system. It can be copied, but the activities of the copy are the copy's activities, not the original's (even if they both dance divinely, with exactly the same degree of divinity). Which is to say, the illusory senses of experiencing self you refer to can be both identical and separate, just as 2 and 2 are separate but identical instances of "2" (more precisely, separate but identical instances of the symbol class "2" for the defining class of "2", or "two", or "II", "dos", et al.). I doubt that will win any of "you" over, though (although I still have high hopes for Nick87.5).
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