Super-Watch Dilemna

There are (at least) two ways to implement a (Star Trek style) transporter:

  1. A space-time wormhole takes you “directly” from here to there, or
  2. We scan you, send the info, make a new copy at the other end, and destroy the original.

Some people care greatly about transporter type; they’d pay to use type #1, but pay greatly to avoid using type #2.  But regardless of the morality of a type #2 transporter, I’m pretty confident that if cheap type #2 transporters were available, but not type #1, many people would use them often, and prefer to think of them as benign, i.e., as if they were type #1.  Humans are pretty flexible about their morality when large economics gains are on offer.

A similar relation applies to two types of super-watches.  Super-watches have one button.  When you are wearing a super-watch, and push it’s button, you turn it on.  Soon after, a person appears next you who looks and thinks just like you and who shares all your memories.  This person is free to walk away, as are you.  The second time you push the super-watch button, it turns off.  And you dissapear.  The second button push is also triggered automatically a given duration after the first push, or if you are about to be harmed by something.  Super-watches with longer durations cost more.

Here are the two ways to make super-watches:

  1. Time Machine + Memory Wipe: The second time you push the button you enter a time machine that brings you back to soon after the moment you first pushed the button,  displaced by a few feet.  It also erases all memories you might have acquired since the first time you pushed the button.  And no, you can’t bring anything else with you in the time machine.
  2. Limited Time Copier:  When you turn on the watch it makes an exact copy of you and puts that copy a few feet away.  When you turn the watch off, or it automatically turns off, you are destroyed.

Now these two ways to implement super-watches produce pretty much the same set of experiences and observable features.  So either you do not care much about  how super-watches are made, or you care a lot about things no one experiences or sees.  As with transporters, I’m pretty confident that if type #2 super-watches were much cheaper than type #1, and offered great economic gains, many more people would use them, and find a way to frame them so they didn’t seem so bad.

Most people don’t see cruelty or morality problems with using time machines, and most people are also pretty comfortable with taking a drug that erases their recent memories.  Many people even like the idea of getting so drunk at a party that they won’t remember what they did the next day.  Yet some people say that while you aren’t obligated to create people, if you do create people you are obligated to give them a good life.  So creating a copy who might only live for a day or a year, and then be destroyed, would be mean, cruel and immoral.  But holding all these views together requires that you care very much about how super-watches are implemented.  Do you?

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  • Matt Knowles

    Yes! Yes, I care very much. I was just trying to ask this question of a co-worker a day or two ago. He was quite nonchalant about your Type 2 tansporter/super-watch, while I am quite troubled by it. Personally, I don’t believe that creating another “awareness” that is just like mine is the same as “moving” my awareness. Any scenario that involves terminating my awareness is the same thing as death, even if there’s another copy out there, unless practical experience teaches me that my awareness is actually shared by the copy, which I find extremely doubtful.

  • MinibearRex

    A truly identical copy can probably be considered to share your own awareness. If somehow (nanotech?) someone made an exact duplicate, atom by atom, of the room I’m in right now, including me, someone watching “both” versions of me would be unable to tell the difference. As far as I’m concerned, I think that in this situation there is only one distinct individual existing. If one room suddenly blinked out of existence, I wouldn’t have died, I would have just gotten smaller.

    That being said, if the two copies were exposed to different stimuli, they would immediately start to diverge. If I turn on a type 2 super watch, the body that seems to appear next to the “original” will diverge into its own consciousness almost immediately, especially if it walked away. Saying that the “original” could then be destroyed without any moral issues is like saying that it’s perfectly acceptable to murder one twin, because hey, there’s another one left.

  • Under the time-travel interpretation, with the “super-watch” one inflicts amnesia on one’s self. Erasing a night’s memories is analogous with alcohol might be enjoyed by many, but erasing a year’s memories will always be considered a serious self-mutilation. Like a surgeon cutting off a limb to a patient’s life, or a desperate mother selling one of her kidneys to feed her children, it is at best a tragic self-sacrifice. (“Paycheck” made this point cinematically in 2003.) Bundling the erasure of a year’s memories with becoming a year younger and traveling one year back in time will only make it slightly less tragic.

    • Jeffrey Soreff

      erasing a year’s memories will always be considered a serious self-mutilation

      Agreed. Ironically, though, I suspect that rather a small fraction of a typical human year is actually remembered with any accuracy. Also, ironically, it is the most recent memories which are clearest – and, if there are technical problems with merging ems’/uploads’ memories into one consolidated memory due to divergence, the recent memories will be those most affected.

  • Constant

    Emotionally I care, but intellectually I think that’s delusional. Derek Parfit settled this for me intellectually.

  • People’s morality is very flexible, but their self-preservation instincts are not. Nobody cares about the economic gains if they think they are going to die, and it seems clear that most people’s intuition is that method 2 results in their death.

    It’s also not surprising news that most people care about more than just the sum total of obsrever-moments in the history of the universe. Nozick’s experience machine and The Matrix are well-known examples.

  • Roman Nastenko

    If I am dead, i don’t care, is there somewhere my copy exists.
    I died, thats all.

  • Jason

    I have always considered that if a type 2 transporter were developed we might never know. People would be tempted to try it for the obvious benefits, but would not be able to report on the extinction of their consciousness. The copy would step out with some cloudy memory of being disintegrated during the transporting process, and to an outsider it would seem as if it operated like a type 1. Word of mouth would spread and it would become part of daily life except for some existential thoughts about it.

    In a sense, the people in Star Trek are either completely selfless, knowing one physical manifestation of themselves will end and another will continue, or completely naive, not realizing they’ve gone too their doom until it is too late.

    As far as the existential question goes, if you eliminate the destruction of the original from the hypothetical, do you experience both consciousnesses? I’m pretty sure the answer is no, so I’m with the fear of disintegration crowd. But if it is yes, or could be made to be yes, that changes things significantly.

  • Scott H.

    How do I know that I didn’t “die” and a have a new consciousness take my place last night as I slept? Or last time I was under anesthesia? Or one second ago?

    • Just because we can’t be sure we aren’t living in the matrix doesn’t mean we can’t or shouldn’t prefer not to.

    • Hedonic Treader

      a new consciousness

      I honestly don’t know what that means. It’s like rationalists still believe in souls. Fascinating.

  • Spandrell

    Ok so what is consciousness. Lets start by answering that.

    • Scott H.

      I’m starting to think I can only answer what a headache is…

    • mjgeddes

      ‘Carve reality at the joints’ by using the following 3 ontological axes with 3 primatives (‘prims’) for each.

      1st axis

      Platonic (PLA) level – Timeless level, universal properties
      System (SYS) level – Computations- things with input, output, process
      Object (OBJ) level – Static objects – things that don’t change

      2nd axis

      Physics (PHY) level – Physical things
      Volitional (VOL) level – Goal directed (living) things
      Mathematical (MAT) level – Logical things

      3rd axis

      Structural (STR) level – The configuration of things
      Functional (FUN) level – What things do
      Representational (REP) level – What things symbolize

      We solve the mystery of conciousness by pin-pointing its position in ‘concept space’: to do this we take the intersection of the 3 ontological axes using the correct 3 base ‘prims’ as coordinates: in fact consciousness is located at the intersection of the System (SYS), Volitional (VOL) and Representational levels (REP)

      So consciousness is the overall representation of a goal-directed system. It’s the interface between the sub-levels (the sub-systems on the functional levels).

      • Spandrell

        Please translate to non-math language

  • GNZ

    I’m with MinibearRex,
    If the two dont diverge its ok, although that sounds rather hard to ensure.

    If they do (for example if i find “I” am the copy marked for destruction) then I could get rather distressed.

  • Hedonic Treader

    But holding all these views together requires that you care very much about how super-watches are implemented. Do you?

    No. I’d use the device routinely just for fun.

  • reader from afar

    It would be nice to get a copy of Robin Hanson to have more of these insightful entries here. 😀

  • Robert Koslover

    I’ve suggested the following before, so I’m a bit reluctant to do so again, but (and I promise to stop after this) please consider:
    1. The only 100% accurate teleporter is quantum-type teleporter. Any other type (non-quantum) teleporter is only an imperfect copy machine, and is fundamentally limited in its accuracy by the uncertainty principle.
    2. A working quantum teleporter operates fundamentally such that it can never generate a separate copy, since the original is always destroyed when the teleported version is generated.

    Thus, if we limit the conversation to either truly accurate teleporters or to quantum teleporters, none of the pesky issues about dual consciousness or the destruction or creation of consciousness can arise. I am aware that it has been suggested (by Robin, I think) that the copying of consciousness (or alternatively, uploading one’s consciousness) really should not require anywhere near the accuracy of a quantum teleporter. Fine. But… are you absolutely sure about that? I mean, what if, by some chance, copying of consciousness really does require such detailed accuracy? If so, then it would seem that basically all of the many philosophical, moral, and (in my opinion) even the religious issues would be quite-neatly resolved by quantum mechanics. I.e., the soul and/or consciousness is always linked to the teleported (which is never duplicated) being.

    If Star Trek teleporters are truly quantum teleporters, then you can step into one with confidence. But if they are not quantum teleporters, then to enter one is to die, and to have a copy of yourself emerge elsewhere.

    • Quantum decoherence in a human brain would occur in less than nanoseconds.

      Is a classical copy that is a few microseconds beyond quantum decoherence not good enough?

      There would be essentially no test that could tell the difference, other than a quantum state comparrison which quantum mechanics forbids anyway.

      • Ilya Shpitser

        There is a difference between “testable” and “true.”

  • rapscallion

    This post seems like a very roundabout way of simply asking, “Do you subscribe to the memory theory of identity?” No, the average person doesn’t, and neither does the average philosopher. Most people are OK with option 1 but not with option 2 because they have other ideas about the definition of personal identity.

    I think few philosophers believe that downloading your “essence/memories” into a new body is even coherent, let alone possible; few think we’re all essentially computer programs and can be copied and transferred as such. It seems like you have to be some kind of dualist to believe such a thing.

    • Konkvistador

      It seems like you have to be some kind of dualist to believe such a thing.

      This part of your comment confused me.

      Are you sure about this? What of those among us who find the mathematical universe hypothesis plausible?

      • rapscallion

        I know that most people who think humans can be “downloaded” consider themselves ardent materialists, but from a philosophical perspective the belief that death is not the end if you can do an information download into another body is not that different from the belief that you can escape death by reensoulment in another body.

        I think the majority of philosophers would agree. If you want to see a debate on this issue between a transhumanist and a philosopher, check this out:

  • NthDegree256

    Rapscallion, I would argue the opposite; that it’s inherently non-dualist to think this way, because it includes the implication that your “essence” and “memories” are all part of your physical state that is being copied, and that there’s no ethereal “personality” or “soul” that is somehow stuck to the original and lost in the transfer.

    A lot of people feel very strongly against Type 2 (of either of the above cases.) I can understand this; my intuition tells me that destroying the “original” is equivalent to murder. That said, my intuition tells me a lot of flat-out wrong things, e.g. that the sun goes around the earth and not the other way around. It doesn’t have a lot of training for this type of situation, and I would very much like to live in a world where we could get over our intuitive hang-ups and make use of Type 2 transporters/super-watches.

  • William P

    There are at least two ways to implement not affecting my conscious experience.

    1. Do nothing, or

    2. Torture someone, but don’t tell me about it.

    Some people care greatly about universe type; they’d be indifferent towards type #1, but pay greatly to avoid using type #2.

    I think you’re right that it doesn’t matter how transporters work, but I don’t think you’ve offered very strong evidence.

  • Evan

    My main problem with all of these scenarios Robin’s been listing for the last week so far seems to be the memory loss. I’d find them much less troublesome if there was some way to load the memories onto the surviving em before one is destroyed.

    I understand that we lose memories all the time, I don’t remember what I had for lunch last year, but those are organically pruned memories, not memories that are simply erased. I think that even if I totally agreed with Robin’s personhood theory I’d still be troubled by memory loss, just because one of them might turn out to be useful. I’d like any memories I’d lose to be lost in the normal fashion.

  • Person copying and memory wiping are manipulations of persons, while worm holes are not.

    I do not want consumerism or other bad stuff implanted in my copy or in my wiped memory by a typically amoral service provider.

  • a novel that deals well with this concept is David Brin’s “Kiln People.” A society in which making clay copies of oneself to do chores etc is routine, and the copies are often destroyed if it’s inconvenient to upload their experiences.

  • snarles

    People who fear the type 2 transporter do so out of an [i]irrational[/i] fear of death.

  • David C

    Star Trek’s transporter is Type 2.

  • Lord

    What if the destruction is extended and painful even if there is no record of it beyond someone possibly watching? I hope most would say no.

  • Evan

    i think peoples aversion to the type two transporter/super watch is rooted in whether they believe people have souls. if they do, then you are either creating a soulless being or murdering a separate, soul-carrying person. either of those scenarios is horrible, but if you simply think of people as a conglomeration of chemicals put together in a very specific way, its no different than moving a modular house

    • I agree, but there are plenty of materialists who feel exactly opposite — that belief in copying or uploading as survival is dualism.

      Their argument would be that if we claim the material body is not itself the identity in question, this implies that the identity in question is non-material, i.e. a soul of some sort.

  • cournot

    Robin seems to like repeating variants of this in his blog though he makes it more explicit here. The fact that most disagree doesn’t deter him. Even if he were right, why does he believe that repeating arguments that were unconvincing to most the first n times make it more likely to be persuasive this time?

    File under: Truth telling isn’t about truth. Part 237

  • KL

    There are any number of books and films in the science fiction genre that explore these ideas (beyond Star Trek, that is). I imagine most people reading this blog are familiar with many such examples. For those who aren’t…

    As far as the watch Robin mentions, check out John MacDonald’s 1962 novel The Girl, The Gold Watch & Everything (which is quite different from the 1980 TV movie adaption featuring Robert Hayes and Pam Dawber).

    As for transporters… For those who are in favor of using Transporter Type #2, the Michael Crichton/Richard Donner novel/movie Timeline is a “friendly” take on the technology. It concurs that breaking down the “original” in order to — in their metaphor — “fax” “you” to a new destination in spacetime really is no big deal, that “you” never feel the death of the original instantiation of “you”.

    Personally I think this is an ethically complacent take on the technology, and sidesteps some of the philosophical questions it raises. Such a view seems to imply that consciousness is simply a nexus in a memory stream of mental sensations, that the sense of “self” is merely a pro-adaptive illusion overlaid on that stream (a position similar to Buddhist concept of consciousness vs. the five skandas — hence Buddhism’s advocacy of non-attachment; to paraphrase the Heart Sutra, “There is no ‘I’ “…), and as long as the memory stream continues essentially uninterrupted, which “I” experiences that stream is actually somewhat arbitrary/unimportant. So the fact that “you” are destroyed and then re-created as part of this technology is totally trivial. “Relax!” they seem to say. ” ‘You’ are never even going to realize that ‘you’ were disassembled and re-assembled, anyway, so what does it matter? You’re getting all hot and bothered over something that is really just ‘metaphysical semantics’… if we engineers didn’t tell you how this technology works, you wouldn’t even be able to distinguish this kind of transporter from Transporter Type #1.”

    Yeah, perhaps not. But it still totally creeps me out.

    Clearly, I’m with the “Avoid Transporter Type #2 At All Costs” crowd. (But then, my Myers-Briggs type is INFJ, my undergrad degree is in theology, and I’m a touchy-feely / sentimental type whose main weakness as a manager is wanting to be liked by those he manages.) As such: for those who think Transporter Type #2 is peachy-keen, including Robin, I recommend you watch the 2006 film adaptation of Christopher Priest’s 1995 novel The Prestige — all the way to the very end. It is extremely relevant to this discussion. I doubt it will make advocates of Transporter Type #2 change their minds, but it may make them face some of the disturbing implications of that technology a little more… viscerally.

    I suspect those who, like me, find Transporter Type #2 troubling/creepy would relate to an idea found in the Koran, that murdering a single person is like murdering an entire world.

    • rapscallion

      I find it very hard to believe people when they say they’d use a type 2 transporter. Since no transporters currently exist or will exist in the near future, there’s little chance that they’ll ever have to walk the walk, so they process the decision in “far” mode, reasoning as though they are 100% confident in all the metaphysical and philosophical decisions they usually defend. I just don’t buy that when the cost of being wrong is death, most won’t get squeamish.

  • I have no moral objections to other people using the type #2 teleporter, for as long as no side effects are known, and these people aren’t emotionally close to me.

    I would not myself use the type #2 teleporter unless it was quantum, because I don’t think we understand awareness well enough to guarantee that my awareness will continue in the duplicated body, rather than coming to an end, and an unrelated awareness arising.

    I would not want people close to me using the type #2 teleporter, because the whole idea of caring about a few people is so you can find comfort in the belief that there exist other, non-self, awarenesses.

    I would be happy using a type #2 copier, however. I would happily create copies of myself as well as other people I like, in order to crowd out the ones I don’t like. 🙂

    • Hedonic Treader

      “[…] to guarantee that my awareness will continue in the duplicated body, rather than coming to an end, and an unrelated awareness arising.”

      Can you be more specific about what you mean by that differerence (between “my awareness” and “an unrelated awareness”)? Specifically, can you point out what natural properties in the physical universe you think constitute the difference? It clearly can’t be shared memories, continuitiy of personality, structural identity etc., because they are all preserved. What other properties do you think there are to constitute this alleged difference, and what reason do we have to believe that they exist in our physical universe?

  • To the anti-type-#2 people: would you use it to escape a life-threatening situation where there is no other option for survival?

    • Erisiantaoist

      I would only use a #2 super-watch to ensure one branch of my conscious experience survives a fatal situation. I would pay more for one which erased the original sooner after creating the copy, though; in a reversal of Robin’s setup. If it created an exact duplicate of me in the same place and erased the original, all within a few Planck intervals, I might not even mind using it much.

  • I’m open to Nozick’s experience machine, as well as wireheading, so I’m probably atypical.

    Surprised Hanson didn’t link to To Be.

  • mjgeddes

    Consider again the ‘three-fold’ hinge on my third ontological axis ‘carving reality at the joints’:

    3rd axis

    Structural (STR) level – The configuration of things
    Functional (FUN) level – What things do
    Representational (REP) level – What things symbolize

    The assumptions and scenarios Hanson paints only extend to the second level (FUN- the functional level). Many high-IQers seem to believe that describing something in purely functional or predictive terms (i.e. Bayesian) is enough to provide an ‘explanation’ of something. Not so! The fact that #1 and #2 are functionally equivalent doesn’t mean the two scenarios are equivalent. This is because REP – the representational level, wasn’t taken into account. Therefore we should be very wary about thinking that #2 is going to preserve our identities.

    Now I have no problem with making multiple em copies and then later having those copies be merged back into one copy. Scenario #1, the time travel scenario) is OK.

    But scenerio #2 I would not risk, based on my ontology, which clearly shows that descriptions on the functional level alone do not fully capture what is going on.

  • arch1

    This stuff always makes me dizzy. Here’s a variant inspired by recent reading which just adds to my disorientation:-) It’s called Transporter Option #3. It’s addressed to those of you who are OK with Transporter Option #2.

    First, I need you to make a Big (but arguably well motivated) Assumption.

    The Big (but arguably well motivated) Assumption:
    Assume you’ve been convinced that our universe is infinite in spatial extent, and that consequently any physically possible configuration of particles and energy within any specified volume of space is exactly replicated an infinite number of times over, within our infinite universe.

    (Why I Claim this Assumption is well motivated: As best I can tell so far from my reading of Brian Greene’s excellent “The Hidden Reality,” the validity of the Big Assumption is actually implied by our best current cosmological theory applied to our best current cosmological data. I invite those who have finished the book and are knowledgeable concerning recent cosmological research, to comment on this assertion.)

    Now, the question: Are you OK with

    Transporter Option #3:
    We just destroy you.

    Sales pitch for this Transporter Option #3:
    We’ve not only made Option #3 a little cheaper than Option #2, we’ve made it greener, too: Specifically, we’ve done away with all the entropy-inducing bother of determining your desired destination, scanning you, beaming your info, reconstituting you at the other end, etc, etc. Not only that, but Option #3 otherwise achieves the same result as Option #2: After all, wherever you want to go, you’re already there, a billion times over (see Big Assumption, above). With bells on, if you like (also without bells on, and – truth be told – whether you like it or not).

    Well, are you OK with it? Why or why not?

    • Cyan

      One might easily prefer Option #2 to Option #3 using reasoning based on Timeless Decision Theory, the short short version of which is:

      Choose as though controlling the logical output of the abstract computation you implement, including the output of all other instantiations and simulations of that computation.

      — Eliezer Yudkowsky (quoted here)

    • This sounds like a variant on quantum immortality, which implies (in a way that may be more horrific than comforting) that nobody really dies. The problem with it is that not all infinities are equally sized. Most universes will not have me spontaneously appear at the destination — most will have me not appear anywhere. If we consider only the ones where I do spontaneously appear somewhere, most of those will have me appear somewhere other than my destination. Most of the cases where I do spontaneously appear in some location would place me in completely random universes devoid of any life, let alone humans, let alone the ones I am familiar with. Thus my expectation would not be to arrive at my destination. With the actual teleporter #2 I have the assurance that the vast majority of universes where I experience my next moment are the same one I remember having been in — exactly as many of them as is the case with transporter #1, or no transporter at all.

    • RN

      Lovely idea. One point is that if you are destroyed here, you will be destroyed an infinite number of times over in our infinite Universe. And those alone are the individuals who are perfectly identical to you; but it is also true that you (individuals identical to you in their previous history) will be not-destroyed another infinite number of times. But in none of these will any of the infinite number of you s think “Well, here I am. That went well” If there is no sensation of having gone anywhere, you haven’t gone anywhere. There’s no reference through memory to having been anywhere else so it doesn’t count as a transporter option. Furthermore, they weren’t you while they were coexisting with you; why should any of them become you the moment you cease to exist?
      But the fundamental problem is that what is thought when you say “this body is my body, these thoughts are my thoughts” can’t be incorporated into an objective representation of the world. It is not a “fact.” It is the essence of subjectivity. Only one of the infinite number of identical yous is the you that you are; but there’s no way of understanding that as a fact–as a part of an objective description of the world. Your subjectivity, your sense of personal uniqueness is both everything and nothing. Objectively, it doesn’t exist. Subjectively, it is the only sense in which you can be said to exist at all.

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  • jrep

    Observably, people care less about hypotheticals than actuals, and less about your actuals than their own. This makes no ethical sense, and possibly not even logical sense, but there it is.

  • This discussion reminds me of an analogous argument I made many years ago with regard to time travel.

    There are at least two basic models for time travel stories. In one, multiple time lines exist “simultaneously.” The time traveler goes back in time, and by doing so creates a new time line that branches off the one where he originated at the point when he arrives and starts changing things. But the old time line still exists and, in principle, he could jump across to it.

    In the other model, there is a single timeline. By going back in time the time traveler erases everything subsequent to his time of arrival, creating a new, and now unique, version of everything thereafter.

    One can, no doubt, make a variety of arguments as to why one model is or is not more consistent or plausible than the other. But in my view, if time travel existed, practically everyone would believe in the first version–because it is a much pleasanter version to believe in. You, by jumping back a century, haven’t killed off everyone you ever knew–you have merely shifted yourself into a different line, leaving all of them unaffected back in the old one.

    • Hedonic Treader

      The second model would allow to undo all suffering that there ever has been – imagine if we could take back the past 500 million years of distress and agony! It would indeed be worth the loss of life. I find it intuitively implausible, however.

      There’s a third model of time-travel used sometimes in sci-fi: The self-consistent model, in which the original present is a result of future time travel to the past. Intruiging and brilliant storylines can be woven around this, often with some kind of tragedy element of incomplete knowledge and sudden revelation for the protagonists. Sometimes stories start out with this promise, providing evidence for the self-consistent model – only to suddenly switch to one of the other ones. Deja vu with Denzel Washington did this. This makes me very angry! ಠ_ಠ

      • I don’t see how anything besides the self-consistent model can genuinely be called time travel. Anything else is really travel to a universe that happens to be in the same configuration as our past universe (plus perhaps the annihilation of our universe and the creation of this time delayed copy).

        I mean if you are supposedly traveling back to t=0 then people at t=1 including yourself better have the memories and experiences caused by your travel to t=0 or that’s an inaccurate way to describe your journey.

        When younger I was unduly impressed by the fact that demanding self-consistency while allowing later events to cause earlier ones could replicate the ‘paradoxes’ of quantum measurement (EPR like effects) with classical particles.

  • I think that much of the valid concern with star trek style transporters comes from people with an epiphenominal theory of mind. Since these people don’t accept that mimicking IO behavior shows that the new being has genuine experiences they are going to worry that the copied being actually lacks any experiences. To this extent I do care how the super watch is implemented.

    I think all the above concerns with identity are misplaced worries and supposing a coherent compelling physical theory of experience had been offered that implied the copies were just as capable of experience as I was I would not care how it was implemented…modulo worries about aging with your time machine implementation.