On Fri, Sep 13, 2019 at 3:07 PM 'Brent Meeker' via Everything List < [email protected]> wrote:
> On 9/12/2019 9:49 PM, Bruce Kellett wrote: > > On Fri, Sep 13, 2019 at 1:41 PM Stathis Papaioannou <[email protected]> > wrote: > >> On Thu, 12 Sep 2019 at 09:38, Bruce Kellett <[email protected]> >> wrote: >> >>> On Thu, Sep 12, 2019 at 2:55 AM Jason Resch <[email protected]> >>> wrote: >>> >>>> On Tuesday, September 10, 2019, Bruce Kellett <[email protected]> >>>> wrote: >>>> >>>>> On Wed, Sep 11, 2019 at 10:18 AM 'Brent Meeker' via Everything List < >>>>> [email protected]> wrote: >>>>> >>>>>> On 9/10/2019 4:30 PM, Bruce Kellett wrote: >>>>>> > Another argument that has been given here before is that if quantum >>>>>> > immortality is true, then we should expect to see a number of >>>>>> people >>>>>> > who are considerably older than the normal life expectancy -- and >>>>>> we >>>>>> > do not see people who are two or three hundred years old. Even if >>>>>> the >>>>>> > probabilities are very low, there have been an awful lot of people >>>>>> > born within the last 500 or so years -- some must have survived on >>>>>> our >>>>>> > branch if this scenario is true. >>>>>> >>>>>> My argument was that each of us should find ourselves to be much >>>>>> older >>>>>> than even the oldest people we know. >>>>> >>>>> >>>>> That is probably the best single argument against quantum immortality: >>>>> if QI is true, then the measure of our lifetime after one reaches a normal >>>>> lifetime is infinitely greater than the measure before age , say, 120 yr. >>>>> So if one finds oneself younger than 120 years, QI is false, and if MWI is >>>>> still considered to be true, there must be another argument why MWI does >>>>> not imply QI. >>>>> >>>> >>>> >>>> Why do you think that measure only increases with age? On an objective >>>> level it only decreases. >>>> >>> >>> As Bruno would say, "you confuse the 1p with the 1pp." I am talking >>> about my personal measure of the number of years I have lived. As I get >>> older, the number of years I have lived increases. If I live to 1000, I >>> have lived more years between 100 and 1000 than between 1 and 100. This is >>> arithmetic, after all. >>> >>> But this discussion has gone off the rails. It started as a discussion >>> of quantum immortality, and the arguments against this notion, even in MWI. >>> The arguments against QI that have been advanced are that life-threatening >>> events tend not to be binary or quantum, but rather we enter a period of >>> slow decline, due to illness or other factors. Consequently, there is no >>> reason for us to expect to be immortal, even in MWI. The other argument is >>> that if QI is true, then you would expect to be very old. This argument was >>> advanced by Mallah (arXiv: 0905.0187) and has not been satisfactorily >>> rebutted. >>> >> >> It is not simple arithmetic if you live to be very old that most of your >> measure is in your older years if you take into account all the copies. >> Suppose there are 10^100 copies of you under 100 years old and then all but >> one copy dies, but that one copy goes on to live to 1000. If you did not >> know how old you were and you had to guess given this information, then you >> would guess with near certainty that you were under 100 years old. However, >> you would also know with certainty that you would live to 1000, and you >> would not notice anything weird happening as you approached your 100th >> birthday. >> > > The trouble with this argument is that you know that at least one copy of > you will survive past 100 years (or past any age, for that matter). Given > that you survive, the probability of survival is one. Taking account of all > the other copies who die does not alter this fact. If you are all your > copies, then your probability of survival under the assumption of QI is > always one. > > Your RSSA assumption is effectively a dualist model -- there is only one > soul that makes you really you, and that soul goes at random into one and > only one copy at any time. Then the chances that this soul-containing copy > is the one that survives, does indeed decrease rapidly with age. But that > is the wrong way to look at it -- there is no 'soul' that makes a copy you. > On the MWI assumptions, every copy is 'you', so since at least one copy > always survives, 'you' will always survive. The number of years you survive > past age 100 is indefinitely large, so you spend more time in those years, > and you have probability one of getting there. > > > As I understand it the theory is that all these 'you's' on all the > branches are potentially the you-of-here-and-now. So the probability that > you-of-here-and-now sees your self as much older than others depends on the > measure of intervals along all the branches. So the question then turns, > as Telmo said, whether this branching structure wide or deep. QI is the > theory that it is infinitely deep. Could it also be infinitely wide? I > don't think so, but in Bruno's theory it could be both. The question seems > to come down to whether one is "copied" by quantum level events that are > amplified to the level of consciousness (which is quasi-classical) very > frequently (continuously?) or rarely. > Yes. QI is possible only in a many-worlds scenario, but that does not necessarily mean that any many-worlds scenario implies QI. As you say, most of life's significant events are quasi-classical in origin, not decoherence amplified quantum events. One could be "copied" by quantum events that are irrelevant to your survival. For example, by the splitting of worlds occasioned by someone shining a laser on a half-silvered mirror. That just increases the number of copies, all of which probably survive that splitting process. As another aside, it seems to me that Stathis's RSSA, with measure along the lifeline decreasing in accordance with Born's rule (as Russell Standish puts it in his book "Theory of Nothing"), is equivalent to a collapse model (or the existence of a dualist "soul" as I put it before). QI requires many worlds. 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/CAFxXSLRUGzHK%3D7u7FizR%3DcgVR68QbJa7wJ9oD14cFh5cwVMfoA%40mail.gmail.com.
