On Fri, Jul 26, 2019 at 1:06 PM Jason Resch <[email protected]> wrote:
> On Thursday, July 25, 2019, Bruce Kellett <[email protected]> wrote: > >> On Fri, Jul 26, 2019 at 2:44 AM Jason Resch <[email protected]> wrote: >> >>> On Monday, July 22, 2019, Bruce Kellett <[email protected]> wrote: >>> >>>> On Tue, Jul 23, 2019 at 2:41 PM Stathis Papaioannou <[email protected]> >>>> wrote: >>>> >>>>> On Tue, 23 Jul 2019 at 11:50, 'Brent Meeker' via Everything List < >>>>> [email protected]> wrote: >>>>> >>>>>> On 7/22/2019 1:35 PM, Stathis Papaioannou wrote: >>>>>> >>>>>> Brain scans might have some bearing on whether not your brain can be >>>>>>> replaced by some equivalent digital device. Once you can do this, >>>>>>> questions >>>>>>> about personal identity become an empirical matter, as has been pointed >>>>>>> out >>>>>>> several times. >>>>>>> >>>>>> >>>>>> The substantive problem is a philosophical one, since by assumption >>>>>> in these debates the copied brain is identical by any empirical test. >>>>>> >>>>>> >>>>>> But what if, as seems likely to me, it is theoretically impossible to >>>>>> copy a brain to a level that it undetectable, i.e. it will necessarily be >>>>>> possible to distinguish physical differences. Now these differences may >>>>>> not matter to consciousness, or they may imply only a brief glitch at the >>>>>> conscious/classical level, but we know from Holevo's theorem that the >>>>>> duplicate can't be known to be in the same state. >>>>>> >>>>> >>>>> I feel that I am the same person today as yesterday because I am >>>>> pretty close to the person I was yesterday, even though if you were to >>>>> look >>>>> at me in enough detail, even using simple tests and instruments, I am >>>>> quite >>>>> different today. It seems unreasonable to insist that a copy of a person >>>>> must be closer to the original than the "copying" that occurs in everyday >>>>> life. >>>>> >>>> >>>> Dealing with this particular worry is one of the strengths of Nozick's >>>> 'closest continuer' theory. >>>> >>> >>> >>> Closest continuer theory is the "Copenhagen Interpretation" of personal >>> identity theory. A stop gap to preserve common sense notions in light of >>> paradoxes that imply the old way if thinking is untenable. >>> >>> As with quantum mechanics, common sense personal identity theories are >>> forced to either abandon any connection linking observer moments (like the >>> zero universe interpretation) or to a universalism that links all observers >>> to a single person (like many worlds). >>> >> >> ????? >> > > > Could you clarify your question? > I have no idea what your statement means. Personal identity theories based on psychological or bodily continuity can >>> always be shown to break down, either by holding the body the same and >>> changing the psyche, or holding the psyche the same and changing the body. >>> >> >> How would one do that when psychological states are clearly closely >> correlated with physical (brain) states? >> >> >> > Bodily continuity is same physical body without discontinuities. A bit > like closest continuer theory. But there's no limit to how radically you > could alter that body over time. This is where things like ageing, amnesia, > memory loss, differentiation of twins, etc. come into play. > Of course, and the theory deals adequately with them all. > For example, you could, over time, change neuron by neuron, until you > looked like and had the mind of Julius Caesar. But under this continuity > of the body your psyche, as you know it, has completely disappeared. > > Continuity of the psyche preserves your mind, but is discontinuous in > physical instantiation. This is where you have transporters, duplicators, > mind simulation, substitution of brain regions, etc. > Closest continuer theory also applies -- although it might not give the results that you appear to want. > Personal identity is multifactorial: it is not just psychological >> continuity or just physical continuity, but a combination of those and >> other factors. >> >> > What are those factors? If personal identity requires bodily continuity > you get closest continuer theory. If it's psychological continuity you get > functionalism. If it's both you get identity only of single thought > moments, if it's neither you get universalism. > It is not a dichotomy of that sort. The theory involves both bodily and psychological continuity -- or at least the closest continuer in this multifactorial space. There may not be any continuers close enough, given some metric over the space, in which case there is no continuer. Or there may be ties, in which case multiple new persons are formed. Personal identity theories, should enable one to answer for any situation: > "what experiences belong to you?" > Define "you" in all these cases below. > Consider some edge cases: > - split brains > - amoeba-like splits (e.g identical twins) > - fusion of previously split brain hemispheres > - transportation > - duplication > - transportation with errors > - memory erasure > - memory swapping > - morphing to another person (with nanotechnology) > - two people morphing into each other > > If the theory of personal identity can't deal with those cases it's > incomplete, if not inconsistent. > Closest continuer theory can provide sensible answers in all these cases, provided one doesn't define it out of existence. With respect to 'memory swapping' and the like, I refer you to the Thomas Mann novella: "The Transposed Heads" (1941). Bruce -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/CAFxXSLTsajAc7ct%3DWUgepKFJagirVhqWyg4qrdcn5%2B9qd_MsfQ%40mail.gmail.com.
