Um, OK, I don't want to get into an infinite argument here. I guess we both understand the other's viewpoint. (For the record: I don't see any reason to accept QTI as correct, but think that *if* it is, it would fit in with the available (subjective) observational evidence - that being the point on which we differ. I also think that for QTI to be correct, a number of other things would have to hold - space-time would have to be quantised, objects in the same quantum state would have to be literally identical (no matter where they happened to be in the uni/multiverse) . . . and, either the multiverse has to exist, or our universe has to be infinite . . . and probably a few other points I can't think of right now!)
Charles > -----Original Message----- > From: Jacques Mallah [mailto:[EMAIL PROTECTED]] > Sent: Tuesday, 4 September 2001 1:12 p.m. > To: [EMAIL PROTECTED] > Subject: RE: FIN too > > > >From: "Charles Goodwin" <[EMAIL PROTECTED]> > >[Jacques Mallah wrote] > > > But there's one exception: your brain can only hold a > limited amount > >of information. So it's possible to be too old to remember > how old you > >are. *Only if you are that old, do you have a right to not > reject FIN on > >these grounds.* Are you that old? > > > >Yeah, that's one of my objections to QTI. Although perhaps > add-on memory > >chips will become available one day :-) > > OK. (And even if the chips become available, you'd > probably only be > able to add a finite # before collapsing into a black hole.) > > > > Right. Do you think you are in an infinitesimal > > > fraction, or in a typical fraction? > > > >Infinitesimal, if QTI is correct, otherwise fairly typical. > Assuming QTI is > >correct and ignoring any other objections to it, it's > *possible* for me to > >be in an infinitesimal fraction - in fact it's necessary. > > Right - which is why Bayesian reasoning falsifies FIN, > but only with > 100% reliability as opposed to complete reliability. > > >but according to QTI I *must* pass through a phase when I > see the unlikely > >bits, no matter how unlikely it is that a typical moment > will fall into > >that phase. Even if I later spend 99.9999999999999999999....% of my > >observer moments seeing the stars going out one by one, > there still has to > >be that starting point! > > Right, again, that's why the reliability is just 100%. > > >My (ahem) point is, though, that none of us ARE at a typical > point (again, > >assuming QTI). In fact we're in a very atypical point, just > as the "era of > >stars" might be a very atypical point in the history of the > universe - but > >it's a point we (or the universe) HAVE TO PASS THROUGH to reach more > >typical points (e.g. very old, no stars left...). Hence it's > consistent > >with QTI that we find ourselves passing through this point... > > Right, consistent with it but only 0% of the time, hence > the Bayesian > argument is to put 0 credence in the FIN rather than strictly > no credence. > > >I'm not arguing for QTI here, but I do think that you can't > argue from > >finding yourself at a particular point on your world-line to that > >world-line having finite length, because you are guaranteed to find > >yourself at that particular point at some (ah) point. > > Right, which is why I'm (now) careful not to make *that* > argument by > arbritarily using one's current age to base a reference point > on. (e.g. in > my reply to Bruno.) Rather, I argue that from being at a > point prior to > some _natural reference point_ such as the "can calculate my > age" crierion, > one can conclude that one's world-line is finite. > > >So I'm rejecting, not Bayesian logic per se, but the > application of it to > >what (according to QTI) would be a very special (but still > allowable) case. > > There are no grounds to reject it in this case, since it would be > reliable almost all of the time. There's no difference > between using a > method because it works for most people vs. using a method > because it works > for me most of the time. At any given time, it works for > most people, too. > > >The basic problem is that we experience observer moments as > a sequence. > >Hence we *must* experience the earlier moments before the > later ones, and > >if we happen to come across QTI before we reach "QTI-like" > observer moments > >then we might reject it for lack of (subjective) evidence. > But that doesn't > >contradict QTI, which predicts that we have to pass through > these earlier > >moments, and that we will observe everyone else doing so as well. > > >I wish I could put that more clearly, or think of a decent > analogy, but do > >you see what I mean? Our observations aren't actually > *incompatible* with > >QTI, even if they do only cover an infinitsimal chunk of our > total observer > >moments. > > Indeed so, I know only too well what you mean. This has > come up more > than once on the list. > I hope you understand why I say it's irrelevant. _Just > like_ in the A/B > case, it would be wrong to not use Bayesian reasoning just > because seeing A > is, yes, compatible with both #1 and #2. Seeing A could even > have been a > way to confirm theory #2, if the rival theory #1 hadn't > existed. The bottom > line is that Bayesian reasoning usually works for most people. > > - - - - - - - > Jacques Mallah ([EMAIL PROTECTED]) > Physicist / Many Worlder / Devil's Advocate > "I know what no one else knows" - 'Runaway Train', Soul Asylum > My URL: http://hammer.prohosting.com/~mathmind/ > > _________________________________________________________________ > Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp
