About Rationally Speaking


Rationally Speaking is a blog maintained by Prof. Massimo Pigliucci, a philosopher at the City University of New York. The blog reflects the Enlightenment figure Marquis de Condorcet's idea of what a public intellectual (yes, we know, that's such a bad word) ought to be: someone who devotes himself to "the tracking down of prejudices in the hiding places where priests, the schools, the government, and all long-established institutions had gathered and protected them." You're welcome. Please notice that the contents of this blog can be reprinted under the standard Creative Commons license.

Thursday, December 06, 2012

Phi2Phi, an amusing app for social philosophy


by Massimo Pigliucci

Philosophers have a reputation for being stuffy, moldy, and constantly behind the times. But in fact the profession has embraced novel ways of doing things, for instance with the highly popular “and Philosophy” book series, a more modern way to introduce the public to philosophical thinking; or via the development of PhilPapers, an incredible online resource to connect professionally and stay up to date on what your colleagues are doing; and let’s not forget the Stanford Encyclopedia of Philosophy, a peer review source that is rapidly becoming the first stop for graduate students and faculty when they want to quickly look up something that is a bit beyond Wikipedia level.

Recently I’ve been playing with another cool little tool, just released: the Phi2Phi app for iPhone and iPad (I don’t think there is a version for Android, yet). It’s produced by Jonathan Weisberg, and it allows a broad, anonymous, community of philosophers and people interested in philosophy to ask each other questions and later check out the answers that have been coming in from the community. The interface is very easy to use, and the submitted questions are organized by broad categories (art, continental, epistemology, ethics, feminism, and so on). The app allows the user to answer any question, after which one can go to the “results” section and see a graphic of the answers so far. A separate button makes it possible for you to ask questions, and a fourth one for you to tell (again, anonymously) the community something about yourself, like what areas of philosophy you are interested in; whether you are an academic philosopher, a graduate student, or someone with a different background; and your level of education. The personal info is then used when you look up answers, because you can filter them to examine what sub-communities of users think, comparing professional philosophers vs lay people, or continental vs analytic philosophers, and so on.

For instance, one of the questions I’ve contributed to concerns what happens when Captain Kirk steps into a transporter device. Possible answers included:

A) Kirk dies, a Trekkie cries
B) Kirk is Kirk1, or Kirk2, whichever you like
C) Kirk is (Kirk1 and Kirk2) before and after
D) Kirk is (Kirk1 and Kirk2) only after transport
E) Kirk is Kirk1 and Kirk is Kirk2, adios transitivity of identity
F) It’s “indeterminate,” in your favorite flavor
G) It’s “nonsense,” colorless, green and sleeping furiously
H) Insoluble paradox
I) Unsure which way to go
J) Huh? What’s this all about?
K) My favorite response isn’t listed (comments please)

As of this morning, there were 41 answers logged in, distributed as follows:


As you can see, a good majority of responders went for option (A), which reflects the metaphysical notion that physical continuity is necessary for personal identity (so much for mind uploading...), though several other of the possible answers got about half the votes as the most common one.

Here is what happens if you filter by users that are involved with academic philosophy:


The relative advantage of (A) is now significantly increased. Finally, if you add a filter that leaves only academics interested in metaphysics, (A) becomes even more clearly the answer of choice, even though now the sample size becomes perilously low, at n=15:


I contributed to a few other questions, and asked a couple of my own (you can see how this can become a very amusing way to procrastinate actual work...), one of my favorite being “What ethical theory do you most identify or subscribe to? The raw (i.e., unfiltered) responses so far (n=45) put virtue ethics in first place (13 votes), followed by utilitarianism (8), existentialism (6), and deontology (5). Interestingly, filtering by academic philosophers pretty much leaves only virtue ethics and utilitarianism standing, and adding an “interest in ethics” filter eliminates pretty much everything but virtue ethics (though, again, now the sample size is low, at 12 total responses).

Of course none of the above should be taken either as a substitute for actually reading and thinking about these topics, or for a scientific survey of a well sampled population. Nonetheless, some of the results may give you a surprising amount of food for thought, and of course the app is going to be more useful as more users sign up for it (it was released on November 21st, and it seems to be doing already pretty well).

I’m not aware of anything similar in the sciences, but it would be equally interesting to, say, probe a community of physicists about what they think of string theory, or the various interpretations of quantum mechanics; or evolutionary biologists on their opinions about species concepts or evolutionary mechanisms. At the very least playing with these social media may make people a bit more cautious when they say — usually without any empirical evidence whatsoever — things like “a majority of philosophers think that utilitarianism and deontology are the best contenders for a workable moral framework.” No, they don’t. At least not those philosophers who are techno savvy and cool enough to use Phi2Phi...

41 comments:

  1. That sounds like a really cool app.

    Regarding Kirk and teleportation, I don't quite understand why option A is so popular with philosophers.

    Presuming 1) that the Kirk who emerges at the end of the transportation process is physically identical to the Kirk that went in, and 2) that there's no untransportable and intangible soul-stuff that makes Kirk Kirk, I don't understand how you can meaningfully say that Kirk has died after being transported.

    If Kirk dies every time he steps into the transporter, it seems to me that that position entails some really weird logical implications. It seems to suggest that those exact atoms that make up the "original" Kirk (Kirk1) are what makes him Kirk1; if Kirk1 is destructively scanned and his pattern is re-instantiated perfectly, then Kirk1 is dead and Kirk2 is born. This seems very problematic to me. Would that mean that if we sequentially replaced every atom that comprises Kirk1 with an identical atom, Kirk1 would gradually cease to be Kirk1 and gradually be subsumed by Kirk2 at the end of the process (when all the original atoms are gone)? And isn't this exactly what is happening to us in real life, but on much longer time scales? (Are our present bodies made up of the same atoms as when we were children?) Is there a certain turnover rate for atoms that is too fast for identity to be maintained?

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    1. Not only that, but there are very good reasons for thinking that talk of "the same atoms" is physically meaningless - see this and this.

      Replacing Kirk's body with a new body made of "different atoms" is arguably a lot like replacing the 9 in "9+3=12" with a different 9.

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    2. Thank you for the links. I had heard that before-- that it's meaningless to talk of "the same atoms"--and I thought about mentioning it as a further objection to option A, but I didn't quite think my physics knowledge sufficient to mount a defense of the notion if the claim was challenged.

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  2. Massimo, you might want to clarify that the thought experiment involves Kirk stepping into a transporter and being "beamed" to two locations at once.

    It is a fun app, I've been playing with it too. I have to admit, the personal identity result surprises me, as answer E (or maybe D) seems like the obvious choice. Is there some devastating argument I'm not aware of in favour of A? The usual arguments in A's favour that I've heard are pretty weak sauce.

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  3. Björn, Ian,

    ah, we’ve got some good disagreement here. Let’s see:

    > I don't understand how you can meaningfully say that Kirk has died after being transported. <

    Because you interrupted (irreversibly) a biological process and essentially simply made a copy of the original. Would you say that a twin brother/sister is the same as the other one? Even before their experiences begin to diverge, and even if they were completely, absolutely identical, surely you’ll agree that they are not the same person, yes?

    The problem here stems from the fact that some people (like Ian?) don’t take the biology seriously enough, and they take the purely logical aspect of the problem too seriously, as when Ian said:

    > a lot like replacing the 9 in "9+3=12" with a different 9. <

    No, it isn’t at all, since all “9” are the same, there is no such thing as a problem of identity in the case of numerals. Presumably there is in the case of people.

    > isn't this exactly what is happening to us in real life, but on much longer time scales? (Are our present bodies made up of the same atoms as when we were children?) Is there a certain turnover rate for atoms that is too fast for identity to be maintained? <

    That’s a good argument, but has at least two flaws that I can see. First, again, it doesn’t take the biology seriously enough. Yes, there may very well be instances were the process of replacement goes too fast and causes the death of the organism in question. Second, there is a fallacy of denying meaningful distinctions just because there are no sharp diving lines. The difference between a full head of hair and a bald one can be covered one hair at a time, but that doesn’t mean that “bald” is a meaningless or useless category.

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    1. Massimo,
      > Would you say that a twin brother/sister is the same as the other one? Even before their experiences begin to diverge, and even if they were completely, absolutely identical, surely you’ll agree that they are not the same person, yes?

      I think it would follow from my position that "I" am not the same person I was just a moment ago, considering that my consciousness/"me" is a product of processes that occur in my brain--processes that constantly change. From this perspective, there is no continuous self, but a temporal sequence of discrete selves, where changes between one self and another are sufficiently gradual so as to give the subjective impression that the self is actually continuous. Accordingly, every change is a death of sorts.

      So, if the twins were "completely, absolutely identical," I'm not sure I would say that they are the same person, but I would say that for the infinitesimal moment before their experiences diverged, they had exactly the same subjective experience. (I'd also suggest that the term "same person" is really insufficient in this case, and desperately needs clarifying.) Regardless, my position entails that the twins may be considered to be different persons, but so must a single individual when compared to itself at an earlier time.

      Applying this to Star Trek's transporter, it must be said that Kirk in some sense dies when he's beamed elsewhere and is replaced by a copy of himself, but the same thing happens to us during every moment of our lives. As far as I can see it, and there is no meaningful distinction between the two scenarios, so if we accept that our self is maintained throughout the changes that occur in our brains over time, then we should accept that Kirk doesn't die when he's teleported.

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    2. > That’s a good argument, but has at least two flaws that I can see. First, again, it doesn’t take the biology seriously enough. Yes, there may very well be instances were the process of replacement goes too fast and causes the death of the organism in question. Second, there is a fallacy of denying meaningful distinctions just because there are no sharp diving lines. The difference between a full head of hair and a bald one can be covered one hair at a time, but that doesn’t mean that “bald” is a meaningless or useless category.

      I wouldn't say that either the concept of the "self" or "bald" are meaningless or useless, but I think the concepts/labels do break down a little bit when sufficiently analysed. Might this not be an instance where our powerful intuition about a phenomenon does not quite capture its essence? I think it's eminently worthwhile to retain the category, but still recognize that it's not absolute, in the same way that we consider "a table" to be a useful label for a macroscopic object and don't abandon it in favour for "a particular table-shaped arrangement of atoms."

      Regarding the rate of replacement and meaningful distinctions...just to probe the issue a little further, I presume you wouldn't consider yourself to be the same person that you are now compared to when you were an infant? (Or if you think you are, replace "an infant" with "at any stage of your choosing during your development as a foetus when the you would consider the differences in subjective experience/nervous system configuration vis-a-vis your current self sufficient to qualify the two of you as 'not the same person'." Phew, not the most elegant sentence.) If you say your current self and your infant self are not the same person, I would ask you when you became who you are now. I would follow up by asking if there were several successive transitions from one person to the next over the course of your life. (As you no doubt can see, I'm trying to move you closer to my position! Please tell me at what juncture I'm not persuading you.)

      The fallacy you refer to...is it the beard fallacy? I'm not sure it's a lethal blow against my argument, considering that it's an informal fallacy. As I have said before in this post, I don't think it's meaningless to use a label or a category, while regonizing that it has its limits, as is the case of "personhood" when placed in the context of a wasteful process of molecular disassembling and subsequent remote reassembling out of a stock pattern.

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    3. Having grown up with Star Trek, I think that I always took for granted that the Kirk who stepped into the transporter device and the Kirk who materialized on the planet surface shortly thereafter (in TV time) was the same Kirk...or that the latter was at least the next best thing - i.e. a Kirk who, owing to his unique occupancy in spacetime and the teleportation process that delivered him there (i.e. the fictional substitute for standard biological continuity), needn't worry about other Kirks running around, competing for the title.

      In other sci-fi dramas, like Doctor Who - where there's a lot of time-travel going on - the situation can get more complicated.

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    4. >Second, there is a fallacy of denying meaningful distinctions just because there are no sharp diving lines. The difference between a full head of hair and a bald one can be covered one hair at a time, but that doesn’t mean that “bald” is a meaningless or useless category.

      I am sensitive to the idea that properties come in spectra, but I don't think it applies well to the personal identity case in question. When we carry out the thought experiment of "replacing atoms" in my body for duplicates, what ARE the two ends of the spectrum?

      Possibility 1: Before any replacing is done, I am alive. After all replacing is done, I am now dead.
      --> Objection: we are talking philosophy, not bioengineering. Ex hypothesi, cell chemistry etc. are not disturbed, so there is no physical mechanism by which death should result.

      Possibility 2: Before replacement, I am conscious. After replacement, I am unconscious (a philosophical zombie).
      --> Objection: the usual objections to p-zombies, which I believe Massimo agrees with & so I will not belabour. Also, it implies that my consciousness "slowly fades" into blackness (or something), which seems absurd.

      Possibility 3: Before replacement, I am alive & conscious as IanPollock1. After replacement, another being is alive & conscious as IanPollock2 - the former is dead.
      --> Objections:
      (a) this already happens to our bodies over the long term.
      (b) assuming that N atoms of my body are replaced gradually, what is the number of atoms n at which the transition between IanPollock1 and IanPollock2 occurs, with the former winking out of existence and the latter winking into existence?
      (c) Assuming there IS no discrete transition (as Massimo seemed to suggest), doesn't that imply that the replacement of even a SINGLE atom makes me ever so slightly less IanPollock1 than I used to be?

      To add something constructive to this debate: my position has been given the label "antirealist" about personal identity. Basically, it means that there are no objective facts of the matter about personal identity, only more or less useful concepts of personal identity for given human purposes. For almost all purposes which concern us, it seems to me that option E is best.

      A challenge for Massimo: to find any substantive, third-person or first-person verifiable difference between the following transitions:

      (a) Kirk before beaming --> "Kirk2" after beaming
      (b) Kirk when he went to bed --> Kirk when he woke up
      (c) Kirk when he died (verified by totally flat EEG) --> Kirk when he was resuscitated 1 km away and 30 minutes later
      (d) Kirk when he died (verified by totally flat EEG) --> Kirk when he was replicated atom for atom and resuscitated 1 km away and 30 minutes later

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    5. There is a Star Trek episode which provides a possible clue to the answer. In the episode "Second Chances" from Star Trek: Next Generation the crew returns to a planet abandoned years ago and finds another Commander Riker. The only differences between the two are reflective of the different lives which each person lived in the intervening time. There is a Riker1 and a Riker2. This leads to the suggestion that in a normal transport the target which is being transported dies and is replaced by an exact duplicate. The only difference being that the new one remembers being transported.
      However, the general idea of transportation in Star Trek shows that the person is the same person who transported with the identity being maintained. There are several shows which revolve around people remembering things which happened while being transported. The question of how a person would maintain consciousness while their components are dissolved is never answered.
      On a technical note. The transporters from Star Trek does not create a new person by building a duplicate from new matter. The objects are actually broken down destructively, compressed into a matter stream which is then sent through subspace and reassembled. I really don't see how a person would still be the same person when your body is torn apart by energy beams.
      The real problem is that Star Trek episodes are written, especially in the original series, by different sci-fi writers who have different visions of identity.

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  4. As Spock may say, a fascinating discussion... but @ianpollock "verifiable" how?

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  5. @ianpollock Wouldn't the first person verification actually be rathrr tricky, as it would potentially need kniwledge of an alternative existence prior to the current one to provide a comparator?

    And as Kirk is in the Nexus now anyway (cf "Generations") isn't this all moot?

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  6. Björn, Ian,

    > it would follow from my position that "I" am not the same person I was just a moment ago, considering that my consciousness/"me" is a product of processes that occur in my brain--processes that constantly change. From this perspective, there is no continuous self, but a temporal sequence of discrete selves <

    Yes, but I would consider that a reductio, and therefore an argument against your position. I think that rejecting the existence of the self is a bad move, just like attributing consciousness and free will to “illusions.”

    > for the infinitesimal moment before their experiences diverged, they had exactly the same subjective experience. <

    But that isn’t the question: are they the same person or not?

    > my position entails that the twins may be considered to be different persons, but so must a single individual when compared to itself at an earlier time. <

    Reductio, again.

    > I presume you wouldn't consider yourself to be the same person that you are now compared to when you were an infant? <

    No, but not in the sense you seem to imply. I am a *continuous* person with my younger self, that continuity being assured by a physical continuity. And it is precisely the latter that is missing between Kirk1 and Kirk2.

    > If you say your current self and your infant self are not the same person, I would ask you when you became who you are now. <

    Gradually, the same way one becomes bald...

    > When we carry out the thought experiment of "replacing atoms" in my body for duplicates, what ARE the two ends of the spectrum? <

    The initial self and the ending self, both biologically and psychologically.

    > there are no objective facts of the matter about personal identity, only more or less useful concepts of personal identity for given human purposes. <

    There may not be objective facts of the matter about different interpretations of quantum mechanics, but the question remains nonetheless interesting. Be careful not to slide into scientism, as you do when you ask:

    > find any substantive, third-person or first-person verifiable difference between the following transitions <

    If you are arguing for a verifiability criterion, you are putting yourself pretty firmly into the positivist camp. And you know what happens to those folks, right? ;-)

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    1. Massimo,
      > Yes, but I would consider that a reductio, and therefore an argument against your position. I think that rejecting the existence of the self is a bad move, just like attributing consciousness and free will to “illusions.”

      I wouldn't say that I'm rejecting the existence of the self, much in the same way that pointing out that the body is composed of cells doesn't amount to denying the existence of the body.

      > But that isn’t the question: are they the same person or not?

      I think I answered that question: no, they aren't the same person. But I also said that the term "same person" needs defining.

      > No, but not in the sense you seem to imply. I am a *continuous* person with my younger self, that continuity being assured by a physical continuity. And it is precisely the latter that is missing between Kirk1 and Kirk2.

      I believe this position is sensitive to a reductio. Consider a brain injury: before the injury, the individual has personality1; after the injury, the individual has personality2. Physical continuity is maintained, but the two individuals under consideration behave very differently. Are they the same person? We can vary the severity of the brain injury to make the event more or less disjunctive.

      Now, compare this scenario with Kirk and the transporter. Arguably physical continuity is lost--though I am uncertain why this is meaningful--but nevermind the personhood of Kirk2, his personality is indistinguishable from that of Kirk1. You would have to privilege this notion of physical continuity above the continuity of personality, even in such extreme cases as brain injury, when considering which sets of two individuals ([pre-brain injury person, post-brain-injury person] and [Kirk1, Kirk 2]) qualify as being the "same person."

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    2. >If you are arguing for a verifiability criterion, you are putting yourself pretty firmly into the positivist camp. And you know what happens to those folks, right? ;-)

      Yikes, I don't think I need to sign on to full blown logical positivism, in order to be suspicious of philosophical theories which posit supposedly very important distinctions ("you will die if you step into that transporter!") that make no empirical difference *even in principle!*

      We can stay close to the heart of the debate by remembering that the real question we're interested in in the Kirk example is, "Should Kirk be reluctant to enter the transporter?" I am saying that, counterintuitive as it might be, I can't find any reason why he should be reluctant, which would not simultaneously be a reason for him to be reluctant to ever go to sleep.

      The best I can do is to articulate a very vague sense that his "thread of consciousness," which extends to the past and future, might be severed (even if a new one started somewhere else). But when you try to justify the "thread of consciousness" intuition, you find that (a) it's damn near impossible to formalize, (b) it's explanatorily 100% superfluous.

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    3. >No, but not in the sense you seem to imply. I am a *continuous* person with my younger self, that continuity being assured by a physical continuity. And it is precisely the latter that is missing between Kirk1 and Kirk2.

      Well, this is begging the question. We already know that the operation of beaming Kirk interrupts physical continuity; what we want to know is whether personal identity is invariant under that particular operation or not.

      I'd say, once Kirk is beamed, there is still a person who remembers being Kirk, thinks like Kirk, looks like Kirk, seduces green women like Kirk, and actually tells you he IS Kirk, only on another planet. I'm looking for some extra kirkness-ingredient that he is missing, but I can't find it!

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    4. @Bjorn:
      >I believe this position is sensitive to a reductio. Consider a brain injury...

      I think all Massimo has to say to dodge the reductio is that physical continuity is necessary but not sufficient for personal identity.

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    5. Ian,
      > I think all Massimo has to say to dodge the reductio is that physical continuity is necessary but not sufficient for personal identity.

      I suppose, but it seems to me that his position gets thornier when we consider gradations of brain injury (ranging from the minutest change to complete brain destruction) versus gradations of physical continuity (ranging from "replacing" one atom to full-blown Trek-portation) when we determine whether personal identity is maintained or not.

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  7. Björn, Ian,

    > I wouldn't say that I'm rejecting the existence of the self, much in the same way that pointing out that the body is composed of cells doesn't amount to denying the existence of the body. <

    Precisely, though it didn’t seem to me that that’s what you were saying before. Thanks for clarifying.

    > I think I answered that question: no, they aren't the same person. <

    Well, since I don’t see a difference between the twins and the Kirks, why aren’t the Kirks not different persons?

    > I believe this position is sensitive to a reductio. <

    As Ian anticipated: not if one thinks that physical continuity is necessary but not sufficient for personal identity, as I do. I think there has to be also psychological continuity, tough the latter is of course a bit more tricky. Oh, and let’s not forget memory (yes, traumas can affect the latter, in which case the person is the same but different...).

    > the two individuals under consideration behave very differently. Are they the same person? <

    Yes (because of physical continuity), but that person is now behaving in a very different matter. That’s less problematic that one might think do: I certainly don’t behave in the same way I did, say, 20 years ago, so I am not exactly the same person, but there is continuity.

    > physical continuity is lost--though I am uncertain why this is meaningful <

    Because when we lose physical continuity we die. At least, that’s most people understanding of the word “dying.”

    > but it seems to me that his position gets thornier when we consider gradations of brain injury (ranging from the minutest change to complete brain destruction) versus gradations of physical continuity (ranging from "replacing" one atom to full-blown Trek-portation) when we determine whether personal identity is maintained or not. <

    As I said before, I don’t have a problem with gradations, since I don’t subscribe to concepts that only admit of a small set of necessary and jointly sufficient conditions to apply (i.e., I’m ok with fuzzy concepts, or cluster/family resemblance concepts). But in the case of Kirk there is a sharp and sudden dis-continuity, which to me makes all the difference.

    > I don't think I need to sign on to full blown logical positivism, in order to be suspicious of philosophical theories which posit supposedly very important distinctions ("you will die if you step into that transporter!") that make no empirical difference *even in principle!* <

    I think you are closer to positivism that you may realize. Regardless, I think the problem, again, is that you don’t take biology seriously enough. A sharp discontinuity in one’s bodily existence is how we think of death, so Kirk died as soon as he stepped in the transporter. The fact that you can (hypothetically, let’s not forget!) reconstitute a perfect indistinguishable copy makes no difference. Say the original Mona Lisa gets destroyed, but you possess a perfect copy, one that not even an art historian can recognize. Would say that you have *the* Mona Lisa? I hope not, and yet there is no verifiable difference between the two...

    > once Kirk is beamed, there is still a person who remembers being Kirk, thinks like Kirk, looks like Kirk, seduces green women like Kirk, and actually tells you he IS Kirk, only on another planet. I'm looking for some extra kirkness-ingredient that he is missing, but I can't find it! <

    See Mona Lisa above.

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    1. >Regardless, I think the problem, again, is that you don’t take biology seriously enough.

      I take your point, and have already noticed before that looking at things from the biological perspective does make my intuitions go the other direction: the biological entity called Kirk gets snuffed out and another, different Kirk takes over. My mental picture involves Kirk's "viewscreen" (so to speak) going black, and then Kirk2's "viewscreen" suddenly turning on in a different location and a different person.

      So I understand the intuitive appeal of this perspective, but it seems very vulnerable to easy thought experiments. What about the guy who dies (no brain activity whatever) and then is resuscitated? Should he have signed a DNR form because the person coming back is "not him?" Because it's "not his viewscreen" that's coming back on? I'm pretty sure this is just nonsense, intuitively appealing as it is.

      >Say the original Mona Lisa gets destroyed, but you possess a perfect copy, one that not even an art historian can recognize. Would say that you have *the* Mona Lisa? I hope not, and yet there is no verifiable difference between the two...

      As I mentioned above, I subscribe (tentatively) to anti-realism about identity. Given a clear definition of the particular conditions for identity that you care about, I'll be happy to tell you whether the Mona Lisa meets them. But I don't think there is any fact of the matter about identity; it's meaningful, but essentially a matter of convention.

      The art historians can decide which conventions they want to adopt; as for me, I don't see a problem with calling an atomically identical Mona Lisa *the* Mona Lisa (and if there are two, *the* Mona Lisas).

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    2. I'm with Massimo. The original Kirk is dead, and each of the two twins is individualized from each other. Per Ian, the "replacement factor" of cells is fuzzy (assuming we're concentrating on brain cells, even, for simplicity's sake).

      In one sense, the replacement of one brain cell by an outside process and not a natural degeneration of a cell with replacement by one theoretically identical due to natural regenesis is to create a different person, if you'll allow me a Forrest/Greene type eternally branching personhood rather than universes idea. My thinking Thought A rather than Thought B makes me a different person. That's whether it's voluntary (per Susan Blackmore and her excellent Zen meditation questions on consciousness) or a Clockwork Orange involuntarism.

      That said, what replacement rate is necessary to say we've killed off the old Gadfly and created a new one? In the brain stem, or even the cerebellum, might be pretty high, eh? But, in the cortex, or a crucial noncortex area like the amygdala, might be pretty low, eh? Even without "replacements," I'm now thinking of Phineas Gage. Did his unfortunate accident kill one person and create another? (See what a thought experiment monster you've created!)

      On the other hand, certain types of strokes have shown that (with the destruction of old neurons but without replacement of new ones) even the cortex can be quite plasticene. So maybe, like with the Star Trek transporter, the "replacement factor" involves "rate" by time as well as "rate" by ratio.

      With Mona Lisas, though, I'd at least lean toward Ian. There, at least, we have a difference that makes no difference, to quote Spock and get back to Star Trek. Whereas, a transportation mechanism is going to make a different Ian, subtle as the differences may be.

      That said, suppose an ambassador at the final end of the transporation has never met Kirk in person before. He has no way of knowing how much or how little the process changed this person, who I'll call Kirk-1.

      But, wait, wait.

      Spock would know any subtle difference, right?

      However, Spock is also getting beamed to different spots, so Spock-1 would, even subtly, have different recollections of Kirk before his latest transportation. (See, you've created a second thought experiment monster.)

      So, what if Scotty-Prime has never been transported? But, with Kirk's latest transportation, it was a bit less fail-safe than normal. Let's say Spock's was, too, but not so badly. So, can Scotty-Prime convince Spock-1 that Kirk-1 is ... "problematic"?

      And, to throw a bomb in the mix ...

      Per a Peter Singer, should we then euthanize Kirk-1?

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  8. Massimo,
    > Well, since I don’t see a difference between the twins and the Kirks, why aren’t the Kirks not different persons?

    It depends on the view of the self. If the self is composite (constituted by discrete "selves"), then the person we were a moment ago is "dead" now, and it would be the same with Kirk stepping into the transporter. From that perspective, Kirk no more dies when he's transported than when he just stands around.

    > in the case of Kirk there is a sharp and sudden dis-continuity, which to me makes all the difference.

    So what would you say if there is not such a sharp and sudden discontinuity, such as when Kirk is gradually replaced atom-by-atom (as per the thought experiment I proposed in my first reply)?

    Let me see if I can state it more clearly.

    1. Let’s say that physical continuity is necessary for personal identity.
    2. Suppose there is a process that switches out the atoms that comprise an object, replacing them one-by-one with exact duplicates.
    3. This process is non-destructive; i.e., should the object be a living being, there will be no disruption in its physiology or biochemistry etc.
    4. So, if this process replaced at once all the atoms that comprise an object, the resultant object would be physically indistinguishable from the original object.
    5. The rate at which this process replaces atoms can be varied.
    5.1. If this process replaces all atoms that comprise an object over time period T, then the resultant object would be physically indistinguishable from the original object after time period T, had it not undergone this process of atom replacement.
    6. Let's say the target of this process is a living being, "Kirk".
    7. Let's call the Kirk prior to the atom replacement "Kirk1", and the Kirk at end of this process "Kirk2".
    8. All atoms that comprise Kirk1 are replaced over time period T, producing Kirk2.
    9. At what value T can we say that the process of atom replacement proceeds too quickly for physical continuity to be maintained, thus resulting in Kirk2 not being the same person as Kirk1? (N.b., as per 5.1, Kirk2 is physically identical in every respect to what Kirk1 would have been after time period T, had Kirk1 not undergone this process of atom replacement.)

    We can set the value of T to anything, ranging from 1 Planck time to Kirk’s entire lifespan, commencing the moment of conception and terminating when that bridge falls on his head in Generations (Worst. Death. Ever.).

    I’d also be interested to know what would happen if we arrested this process at N% completion (again, ranging from a single atom in the brain being replaced, to the entire body, brain and all).

    Also, one final semi-short thought: let’s say we ripped Kirk apart, atom-by-atom, and reconstituted him one Planck time later on the same spot, from the “same atoms”; would physical continuity be maintained, and would Kirk have died?

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  9. Ian,

    > What about the guy who dies (no brain activity whatever) and then is resuscitated? Should he have signed a DNR form because the person coming back is "not him?" <

    I don’t see the force of this at all. Clearly it’s the same guy, because there is both physical and historical (as well as memory and psychological) continuity.

    > The art historians can decide which conventions they want to adopt; as for me, I don't see a problem with calling an atomically identical Mona Lisa *the* Mona Lisa (and if there are two, *the* Mona Lisas). <

    So here is, I think, the crux of the problem: you not taking seriously the biology is at least in part a result of not taking seriously the history of a given object (or person), which I surmise is the result of your commitment to a logic-only view of the problem.

    What I mean is that in my opinion there is absolutely no doubt that there can only be *one* Mona Lisa, the one historically painted by Leonardo. Everything else is a copy, and I’m pretty sure you won’t find any art historian agreeing with your position here.

    The same goes for people: Kirk2 has no historical continuity with Kirk1 because the physical, spatio-temporal continuity has been interrupted by the transporter. So Kirk2 is a copy exactly in the same sense in which Mona Lisa-2 is a copy. The originals are dead (or destroyed), alas.

    Björn,

    > At what value T can we say that the process of atom replacement proceeds too quickly for physical continuity to be maintained, thus resulting in Kirk2 not being the same person as Kirk1? <

    The answer to your question is empirical, and to be more precisely biological (see my comments above to Ian). I find it interesting that you and Ian keep asking for empirically verifiable differences and then base your arguments on physically (and certainly biologically) impossible thought experiments. Thought experiments are useful to flesh out and think about our intuitions, but they do not settle matters of fact. Only science can do that.

    > I’d also be interested to know what would happen if we arrested this process at N% completion ... Also, one final semi-short thought: let’s say we ripped Kirk apart, atom-by-atom, and reconstituted him one Planck time later on the same spot, from the “same atoms”; would physical continuity be maintained, and would Kirk have died? <

    I don’t know, since the answers to those questions are, again, empirical. I’m not sure how you can be so confident about what would happen, unless you think you can settle these issues by logic alone, which I don’t. (Your latter thought experiment, by the way, is known to be physically impossible, so what’s the point?)

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    1. Massimo,

      Actually, the questions aren't empirical. If you look at my list, you will see that items 3, 4 and 5.1 stipulate that the process produces physically indistinguishable copies of the original. Hence, there can be no possible empirical investigation into the matter. This is in line with the original thought experiment, concerning Kirk and Star Trek's transporter, where it's accepted as a given that Kirk2's physical characteristics are the same as Kirk1's--the question we're considering is whether Kirk2 is the same person as Kirk1. What possible empirical test could be devised to settle this entirely philosophical question?

      The point of both my thought experiments is certainly to explore our intuitions on this matter. You say physical continuity is necessary for personal identity, and I propose a scenario where there's a gradual diminishment of physical continuity, represented by a replacement of atoms. While the presentation might be fanciful, it's not entirely absurd, since the material composition of our bodies is not invariant over our lifetimes.

      So, I haven't asked for any empirically verifiable differences, but have only considered the entirely metaphysical question whether physical continuity is necessary for personal identity.

      Stated as succinctly as I can, I ask the question "If physical continuity is necessary for personal identity, then how can personal identity be maintained over our lifetimes, given that we are not constituted of the same matter as infants as when adults?"

      The thought experiments contort and twist this question a bit, but that's the essence of it, and I think it's directly relevant to your question regarding Kirk's metaphysical fate when he steps into the transporter.

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    2. >I don’t see the force of this at all. Clearly it’s the same guy, because there is both physical and historical (as well as memory and psychological) continuity.

      The force of this is that a consciousness is totally extinguished at time & place A, then tokened anew at a completely different time & place B (I forgot to emphasize the location change in my last comment).

      This interrupts any spatio-temporal continuity between the two consciousness-tokenings. Then all there is which might be able to preserve personal identity is the physical continuity of a bunch of dead flesh. I don't see how you can say that this is the same person as the one who died, and yet reject transporter-Kirk. It's not as if there is a soul being dragged along by the dead physical body!

      >So here is, I think, the crux of the problem: you not taking seriously the biology is at least in part a result of not taking seriously the history of a given object (or person), which I surmise is the result of your commitment to a logic-only view of the problem.

      I do take history seriously, I just think the history of the "copy" Kirk is the same (in all relevant aspects) as the history of the "original" Kirk. The question of whether the transporter makes a difference to such things is precisely what is at issue.

      Once again, I want to emphasize that aside from any particular theory of personal identity, the question we really care about is "does Kirk have anything to fear from the transporter?" I agree that his spatio-temporal continuity is interrupted; but it is an open question whether losing spatio-temporal continuity kills Kirk. Sure, you can *define* death that way, but that isn't very interesting.

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    3. >The answer to your question is empirical, and to be more precisely biological.

      Well, no, it's an empirical question what replacement-rate would kill you (in the philosophically uncontroversial sense of "kill" as in "Aghh aghh I'm dying, the pain").

      It's a philosophical question what rate would cause you to become a different person (however you cash out that concept), and it is a philosophical question whether it makes sense to even ask the question.

      And the fact that this far-fetched thought experiment is actually happening to us is a lovely reductio of any personal identity theories that locate personhood in "particular atoms."

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  10. Two comments.

    First, if I'm reading the numbers correctly, technically a plurality, not a majority, voted for option A.

    That said, if I understand Ian correctly, the original Kirk is dead and Kirk 1 and Kirk 2 are two separate new people.

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    1. Not quite... Kirk1 and Kirk2 are certainly two separate people, but it would be odd to call them "new" qua persons. They both have just as much claim to being pre-transport Kirk as each other, and as pre-transport Kirk.

      As for the pre-transport Kirk being dead, it depends on what you mean by "dead." Certainly if he was *only* scanned destructively, he would be dead. But ordinarily if we think somebody's dead and then we meet them and they say "Nope, I'm alive, and here are all my old memories etc. as evidence," we concede they are alive.

      I think Kirk is still alive in the same sense as a resuscitated dead man is still alive.

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  11. If Kirk 2 identifies as being a continuation of Kirk 1, then Kirk 2 is Kirk1 with the added experience of being teleported. If Kirk2 believes he is a different person, then he is a different person. If Kirk1 or 2 allows others – learned philosophers and scientists as they may be – to determine his identity status then Kirk has a problem with individuation and should consult a psychiatrist (perhaps a Jungian). The fact that the question is posed at all may indicate a culture in which humans are objectified and individuals’ subjective experience devalued.

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  12. What would happen if (either by malfunction or intentionally) the original Kirk was not destroyed? In that case, wouldn't it be obvious that Kirk1/2 is not Kirk? A transporter is essentially a cloning device plus transportation of the clone. With fun effects if something goes wrong, see The Fly ;-)

    So while in theory, if everything goes right, it doesn't make a difference, in practice shit always happens eventually. Under current law, I am pretty sure original-Kirk would be considered dead (unfortunately, http://lawandthemultiverse.com doesn't generally write about SF&F, but maybe we can get them to make an exception - they just made on for the Hobbit). Future law would probably say sth like Kirk1=Kirk if everything is ok, with endless rules on what would happen in non-ok scenarios.

    A good SF mystery novel using sth like this in its plot is "Martian Knighlife" by James P. Hogan.

    [Btw, fun language fact: in German, we probably wouldn't be having this discussion, at least not in the same way, as we have two words for "the same". "Dasselbe" means something in the direction one and the same (i.e. there can only be one), "das gleiche" is more an equality relationship. The people wearing the same clothes are wearing "die gleichen" clothes, but they can never wear "die selben" clothes, at least not simultaneously. Kirk1 is "der gleiche" as Kirk, but not "derselbe". Massimo is subscribing to the second meaning of same, Ian et all to the first.]

    Cheers
    Chris

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    1. chbieck: Thanks for that little German lesson!

      So, to reframe my previous comment in this thread, so long as we don't end up with multiple Kirk clones in the same approximate region of spacetime - thereby creating an obvious "der gleichen" problem of competing claims to the Kirk identity - commonsense/intuition will favor a "die selben" interpretation, as my childhood Trekkie did. [I don't know much German, so forgive me if I used those terms too loosely.]

      Still, the logic is the same, which leads me to believe that the argument pivots on (English-language) semantics/convention.

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    2. mufi,
      not really. Whether Kirk0 is around or not (why SPACEtime, btw? Would it really matter if the clone where at the other end of the galaxy/universe?), Kirk1 can never be "derselbe", just like Massimo is arguing.

      Basically we are faxing Kirk, aren't we? While the fax is mostly accepted in lieu of the original, I don't think anybody would say it is the original.

      I still think we are on the same page, because I wouldn't chose A either. Of course Kirk is dead, by I see no reason for a Trekkie to cry - since the clone is postulated to be perfectly identical, I will accept it in lieu of the original ;-) Only in the fictitious setting, of course...

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  13. Ian,

    > This interrupts any spatio-temporal continuity between the two consciousness-tokenings. <

    You are making big assumptions there. If the guy is really dead, then I don’t think he will come back (I don’t believe in resurrection). So the continuity has only superficially been interrupted.

    > It's not as if there is a soul being dragged along by the dead physical body! <

    No, but there is some relevant biological phenomenon being dragged along, otherwise, again, the guy would be dead. Death is irreversible, as far as we know.

    > I do take history seriously <

    Sorry, Ian, but you don’t, as it is clear from your treatment of Mona Lisa.

    > "does Kirk have anything to fear from the transporter?" <

    Hell yes! He’s about to die!

    > it is an open question whether losing spatio-temporal continuity kills Kirk. <

    Not if you take biology seriously it isn’t.

    > the fact that this far-fetched thought experiment is actually happening to us is a lovely reductio of any personal identity theories that locate personhood in "particular atoms." <

    It isn’t, in my opinion, it only highlights the fact that some people have a physical-biological concept of persons (me) while others like to think of them in purely logical form (you). Looking forward to your mind uploading, Ian? ;-)

    Björn,

    > the questions aren't empirical. If you look at my list, you will see that items 3, 4 and 5.1 stipulate that the process produces physically indistinguishable copies of the original. <

    Yes, but in so doing you (and Ian) sneak in assumptions that seem to violate everything we know about biology. That, to me, makes any further point moot.

    > You say physical continuity is necessary for personal identity, and I propose a scenario where there's a gradual diminishment of physical continuity, represented by a replacement of atoms. <

    We already know that gradual replacement isn’t problematic, since it happens naturally. But Kirk’s dematerialization is nothing of the kind.

    > If physical continuity is necessary for personal identity, then how can personal identity be maintained over our lifetimes, given that we are not constituted of the same matter as infants as when adults? <

    You seem to be confusing physical continuity with physical identity.

    Gadfly,

    > With Mona Lisas, though, I'd at least lean toward Ian. <

    I don’t get it. That case seems to me a slam dunk. Obviously the only ML is the one originally painted by Leonardo. Anything else is by definition a copy, no matter how good or even absolutely perfect. It’s really the same with twins, or, better, cloning. And none of those cases is different from Kirk’s, as far as I can see.

    Neil,

    > The fact that the question is posed at all may indicate a culture in which humans are objectified and individuals’ subjective experience devalued. <

    I have no idea where this comes from. Nobody’s questioning Kirk2’s feelings or right. It’s a metaphysical question, not an ethical one.

    Chris,

    > What would happen if (either by malfunction or intentionally) the original Kirk was not destroyed? In that case, wouldn't it be obvious that Kirk1/2 is not Kirk? <

    Yup, again the same as the cases of the Mona Lisa, the twins or the cloning.

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    1. Massimo,
      > Yes, but in so doing you (and Ian) sneak in assumptions that seem to violate everything we know about biology. That, to me, makes any further point moot.

      Perhaps, but then you should say the same of your question regarding Kirk and the transporter, because the only difference between my proposed process and Star Trek's transporter is that the former is gradual while the latter is instantaneous. If you didn't think the question merited serious philosophical consideration, why pose it in the first place?

      > We already know that gradual replacement isn’t problematic, since it happens naturally. But Kirk’s dematerialization is nothing of the kind.

      Yes, which is why I wondered how fast the rate of replacement could be. Remember, as Ian pointed out, we are NOT asking the question whether this replacement/teleportation will produce a dead Kirk--for the sake of the thought experiment, both mine AND Star Trek's, it's assumed that Kirk2 will be physically identical to Kirk1 (i.e., he will be non-dead)--rather, we ARE asking the question whether this replacement/teleportation will produce a different person than the original Kirk. This removes us entirely from the domain of the biological and brings us into the realm of the metaphysical.

      > You seem to be confusing physical continuity with physical identity.

      I don't think I am. You have said many times in this discussion that you think that physical continuity is necessary for personal identity, and since there's no physical continuity between Kirk1 and Kirk2, they must be considered different persons.

      I accepted your premise and sought to explore what would happen to Kirk's personal identity if the physical continuity between his future and past instantiations was gradually diminished. Just as with the transporter, at the end of this process Kirk2 would not be physically continuous with Kirk1, since all matter that originally comprised his body would have been replaced. Is Kirk2 the same person as Kirk1?

      This bears directly on the question whether the "physical-biological" concept of personhood that you subscribe to is coherent.

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    2. I lean toward Ian on the Mona Lisas because they don't have consciousness. I'd say the same about two Parma hams or two wedges of Stilton with similar duplication. I still disagree with Ian on the Kirks. If the "original" Kirk were not destructively scanned, we'd never say Kirk-1 or Kirk-2 have a claim to be the original. Also, with two Kirk duplicates rather than just 1, Ian ignores another quantum effect — one of them is "created" before the other. The can't literally be created at the same time. (Of course, we can't tell which one was created first, also per quantum theory.)

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  14. Massimo,

    I am probably off the planet but surely the only person who can determine Kirk's identity status is Kirk and not some outside observer. If one sees a figure walking down the street and determines that it is Kirk then as the figure comes closer one determines that it is not Kirk at all, then to the observer the figure is at one time Kirk and at another time not. Yet the figure knows all of the time his identity - the observer may be mistaken both times. We may simply have to take Kirk's word for it. We may never know what it is like to be a bat and we may never know what it is like to be Kirk.

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  15. Björn,

    > If you didn't think the question merited serious philosophical consideration, why pose it in the first place? <

    You are making the assumption that metaphysics is entirely independent from science (in this case, biology). I don’t think so, which means that for some metaphysical questions one does need background information from the relevant science. In this case, the crucial difference is whether biology allows a change faster than a given rate X. I don’t think it would, which bears on the metaphysical question.

    > we ARE asking the question whether this replacement/teleportation will produce a different person than the original Kirk. <

    Yes, as the cases of the Mona Lisa, twins, clones and the particular instance in which the original Kirk is retained through a transporter’s accident make clear, I think.

    Let me try a different angle, perhaps it will help. You and Ian seem focused on logical possibility, while I insist on bio-logy informing our metaphysics (just like naturalist metaphysicians insist that one can’t do metaphysics without physics). The situation is analogous, perhaps, to Chalmers’ zombies. He thinks he has established something about the world (some kind of dualism) based on the fact that a particular hypothetical scenario doesn’t seem to violate any laws of logic. But he has established nothing of the sort of course, because physical possibilities are much narrower than logical ones (i.e., logic puts only weak constraints on what can be). Similarly here: the transporter seems to present us with a logical possibility that invalidates commonsense notions of individuality. But that’s because the biology (and physics) isn’t seriously taken on board. Once it is, I doubt there is any way to escape the conclusion that Kirk dies as soon as he steps in the transporter, and whatever materializes on the other side is a copy, albeit a very good and possibly indistinguishable one.

    Neil,

    > the only person who can determine Kirk's identity status is Kirk and not some outside observer. <

    No, Kirk can only tell us who he *thinks* he is, that’s nowhere near answering the metaphysical question. It would be (sort of) like asking two twins which they think is the original...

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    1. Massimo,
      Perhaps I gave the wrong impression, but generally speaking I definitely agree with you that metaphysics is NOT entirely independent from science. It's just that in this particular case with Kirk and the transporter, I don't see science deciding the matter. Why? Well, the facts don't seem to be in question.

      Let's review:
      1. Both instances of Kirk (before and after transportation) are physically indistinguishable. This entails that memories, personality quirks, beliefs etc. are all preserved, just as if Kirk hadn't been transported in the first place.
      2. There seems to be a physical discontinuity, where the material being that is Kirk1 is obliterated, only to be reformed at a distance as Kirk2. (Whether or not it's meaningful to say that the matter that comprises Kirk2 is different from the matter that comprised Kirk1 is a question for physicists, and I'm not qualified to answer it, but from Ian's links early in the discussion, I'd suspect it's not meaningful.)

      Are there any more questions of fact that the science can address?

      Otherwise, what remains are metaphysical questions.
      1) Are Kirk1 and Kirk2 different persons, their physical indistinguishability notwithstanding?
      2) What should be the critera by which we determine continuity of personal identity? Physical continuity? Continuity of personality? (For example, when deciding which of the members of these sets qualify as being the "same person," which factors are relevant to consider: [Kirk1, Kirk2] , [Kirk at time T, Kirk at time T+n] [pre-brain-injury person, post-brain-injury person])
      3) Examined logically, is the notion that physical continuity is necessary for personal identity coherent?
      4) Examined logically, is the notion that continuity of personality is necessary for personal identity coherent?

      (I'm probably forgetting something, but you get the point.)

      > [Regarding Chalmers, zombies, logic versus biology, and that the science fatally complicates the logical case]

      First, I agree with you regarding Chalmers and zombies.

      Second, some of what you say here I address above.

      Third, to summarise my point of contention: I don't see any empirical facts that are in dispute, but that the only remaining questions are philosophical/metaphysical.

      Am I wrong in thinking there are no empirical facts that are in dispute? Or am I making some invalid logical inference from these facts? If so, I would very much like to know where I go wrong.

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    2. Thanks Massimo

      '... Kirk can only tell us who he *thinks* he is ...'

      "Je pense donc je suis". Kirk thinks he is Kirk, therefore Kirk is Kirk. I would rather take his (or their) word for it than that of an observer. Although if Kirk2 thinks he is Jesus and that he has risen from the dead ... ! I guess I would be forced to take his word for it.

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  16. Björn,

    thanks for the further clarification, and I don’t think either you or Ian go “wrong” somewhere. I simply find your arguments unconvincing (as opposed to, say, mine...). That’s usually the way good discussions in metaphysics go, hardly anyone has a knockdown argument.

    > Both instances of Kirk (before and after transportation) are physically indistinguishable. This entails that memories, personality quirks, beliefs etc. are all preserved, just as if Kirk hadn't been transported in the first place. <

    Correct. But remember my examples of the twins, Mona Lisa, etc. In those cases too there is no discernible physical difference, nor any difference in behavior or characteristics, and yet most people would say that there are two twins, not one, and that there is only one original Mona Lisa (pace Ian, apparently). The case is even more compelling when we consider the possibility of transporter accidents that leave the original in place (as it has, in fact, happened throughout the ST series). In those cases it is undeniable that there is a Kirk and Kirk-copy. Since the difference between those cases and “normal” transport is that in the latter instances the original is destroyed (i.e., killed), I find it hard not to accept that Kirk-copy is, indeed, a copy — as much as it is functionally identical to the original.

    > There seems to be a physical discontinuity, where the material being that is Kirk1 is obliterated, only to be reformed at a distance as Kirk2. <

    Correct, and you are correct that the materials being different for Kirk2 doesn’t matter (because we also change materials throughout our lives). To me vaporizing a person amounts to kill him, and this is were the biological fact becomes relevant:

    > Are there any more questions of fact that the science can address? <

    Yes. The best biology we have tells us that slow replacement of parts over time is compatible with life. A total and sudden vaporization, instead, means certain death for the individual. Which leaves only a copy as the metaphysical option on the other side of the transporter beam.

    > Are Kirk1 and Kirk2 different persons, their physical indistinguishability notwithstanding? <

    Yes, for the same twin/Mona Lisa/Kirk+accident reasons summarized above.

    > What should be the critera by which we determine continuity of personal identity? Physical continuity? Continuity of personality? <

    That’s a good question. I think that spatio-temporal continuity, memory and personality are all necessary, and none individually sufficient.

    > Examined logically, is the notion that physical continuity is necessary for personal identity coherent? <

    Yes, but it is not sufficient.

    > Examined logically, is the notion that continuity of personality is necessary for personal identity coherent? <

    I think so, I have not seen any argument to the effect that it wouldn’t be. I hope this helps!

    Neil,

    > Although if Kirk2 thinks he is Jesus and that he has risen from the dead ... ! I guess I would be forced to take his word for it. <

    Which is why I think your position is hard to defend. There are all sorts of delusional people who think they are Napoleon. While I have no reason to doubt their inner convictions and psychological situation, I am pretty sure they have no right in calling themselves Napoleon, on the ground that Napoleon was a particular historical figure who is now dead and who is not them.

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  17. Touché Massimo:

    But surely you cannot doubt the physical evidence of an artefact recently excavated in Palestine in the shape of a crucifix with the trademark 'Transporter (made in Rome)' in Latin and barely legible inscribed near its base! Is there nothing new under the sun?

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