Just because those people are dead in this universe doesn’t mean they’re not alive in other universes. Basically, they might only be alive in some very small ratio like (1/Graham’s number) of the universes that have formed since their birth, but those are the only universes they can experience.
Quantum immortality means a continuous, never ending existence. Not dying, and then getting somewhat resurrected extremely briefly and sporadically.
Again, you don’t need continuous existence, you need continuous experience. A hypothetical sentient computer would still conceivably have continuous experience even if turned on for a few seconds every million years or so.
I sometimes like to distinguish between continuing to exist as an exact copy due to chance, and continuing to exist as an exact copy due to a chain of causality. There is no chain of causality between me and a Tegmark-clone umpteen gazillion parsecs away, or between me and a Boltzmann-brain umpteen gazillion years in the future.
But there would be a causal link between me and and a re-located me created by quantum-tunnelling somewhere outside the impact zone of a Chicxulub meteor, and between me and a clone created by arbitrarily sophisticated, post-hoc, simulation technology. Indeed, in a small but possibly non-zero set of universes, a technology clone of this kind could contain exactly the same information as my own mind, due to a combination of luck and skill.
That would satisfy both the constraint that the end result would need to be both identical to myself, and to have a direct causal link. Don’t imagine, however, that I think this would be either likely or desirable.
However Mr Chopra insists on getting paid right here in this Universe before he will tell you about his grand theory of quantum consciousness. Perhaps that is wise of him; he probably realizes the vast majority of his audience as as likely to be miserly scoundrels in another Universe as this one. Take your chances with the Quantum Multiverse, but pay here first, please.
Boltzmann brains manifestly do not give you continuous experience, though.
You are A. You die. You have no more experiences, ever. A Boltzmann brain ‘B’ spontaneously pops into existence. It believes it has had the same experiences as A did prior to A’s death. (Or rather it would if it lived long enough to access its memory, but whatever.)
Which is fine and all for B, but it doesn’t do jack for A. A still died without the experiences of B. The two are actually unconnected - B could have existed before A in this scenario, or concurrently with A, and it changes nothing for either A or B.
The computer example is a little different, in that it actually has continuous existence and what happens to ‘A’ causally effects ‘B’ - this allows one to reasonably say that B is A, from a definitional standpoint, with a fairly solid philosophical grounding that Boltzmann brains do not provide.
All that’s needed for continuous experience is a sequence of conscious states that are continuous with one another; that, a Boltzmann brain can give you. Indeed, there’s also a philosophical thought experiment known as Boltzmannian immortality. As the matter is put in this article:
Greg Egan’s idea of “dust theory” (see Egan 2009) seems to be the next step in developing the idea of QI [Quantum Immortality] […]. In dust theory, something similar to QI happens in every observer-moment; such moments could exist completely separately from each other, as random patterns in infinite “dust,” or as Boltzmann brains, but could look subjectively connected “from inside” based on their similarity.
That’s not to say there aren’t philosophical objections that could be raised against the underlying notion of personhood. But that notion does indeed follow from the most widely accepted discussion of the matter, originating in Parfit’s Reasons and Persons. Loew in the first article above calls this the ‘psychological continuity view’, and reviews some of the arguments for it, notably the ‘transporter’ scenario (quoting Parfit).
In fact, making a sort of ‘causal’ view consistent with modern physics would be hard work: elementary particles carry no name tags, so that there is no fact of the matter regarding what lump of matter is made out of ‘your’ particles, and what exact copy of you is made out of ‘different’ particles. If you carry an electron from A to B, and one from C to D, then there is no fact of the matter regarding which electron arrived at B, and which at C; in fact, the relevant Feynman series will contain terms for both possibilities. Indeed, it will also contain terms for both electrons spontaneously annihilating with positrons into photons, these photons then pair-producing electron-positron pairs, whose electrons go to B and D.
So there’s likewise no difference if a person gets disassembled into their constituent atoms, and reformed at some other place, or if the ‘original’ atoms just disperse, and an identical copy spontaneously forms. In fact, there’s no difference if a person walks from one place to another: all your atoms could spontaneously tunnel to Alpha Centauri, and be replaced with identical ones, without it making one whit of a difference to the physics (and indeed, there will be a term for this process in the perurbation series). (Which incidentally also makes short work of the ‘tunneling’ distinction @eburacum_45 wants to draw: there’s no difference, at the microphysical level, between tunneling somewhere and just spontaneously reforming there, because there’s no fact of the matter which particles arrived at that point.)
So again, there really is no notion of ‘continuous existence’ as you presume it, not at the microphysical level. Consider halting the computer at step n, disassembling it into components, and reassembling it in the state corresponding to step n+1: if you swap some out, do you think it somehow ceases to be the same? It will perform the same computation, and if the computation constitutes conscious experience, will have the same experience, too. So what if you assemble it from completely different parts? Say the original computer is disassembled into components, which get thrown onto heaps of identical computers, from which a new computer is built by randomly drawing parts, and assembling them into a new one in the state of step n+1: do you need a certain minimum fraction of original parts for it to be considered the same computer?
Say the computer is enumerating the digits of pi: if it’s gotten to 3.141592 before the disassembly, it will continue right along with 6535… upon reassembly: the program execution is continuous. But that’s true for every given program, including those giving rise to conscious experience (of which I don’t think there are any, incidentally, but that’s another discussion). Indeed, some such view must be true if you ever hope to upload your mind into a computer—because all that’s done there is copying your brain state, in whatever way; but if you can copy it, you can also, say, write it down (on lots of paper, say), and then just assemble a computer in the right state. But that computer won’t be distinguishable (physically) from any computer that just randomly assembled itself in that state, so if you think your uploaded version is still ‘you’, then you also ought to think the entity from the randomly assembled one is (or appeal to some extra-physical notion of identity or experience).
Should have been ‘…heaps of identical parts’.
By this argument, if you have an assembly line pumping out a thousand copies of the same doll and dumping them in a big pile, you’re saying that all the dolls in the pile are the same single doll, since they’re all effectively identical, and therefore there is only one doll in the pile.
Or if you require something with a mental state, Dell pumps out lines of computers with the same hardware arrangement and the same data imaged into their hard disk. By the argument you’re forwarding, all of those computers are literally a single computer, and they of course continue to all be the same single computer no matter how they later diverge, since they all are the same single computer and changing over time doesn’t change that. Therefore each subline Dell has released has only had one computer in it, and there are a lot fewer computers in the world than it looks like there are.
I don’t disagree that some addleheaded philosopher has advanced these sorts of notions, but I disagree that they have any merit whatsoever.
Questions of definitional identity are always going to be a little fuzzy, since technically everybody is a completely different person from who they were a second ago due to all their subatomic particles moving around, but if we used that as the rule then property law would get all complicated and stuff. But going too far the other way is wrong as well.
And none of this changes the fact that no matter which tortured argument you use, once person A gets hit by a bus and dies nothing that happens to persons B, C, or D helps them, be they in an alternate timeline, an alternate dimension, or in a shortlived swirl of random particles that happened yesterday.
No, come on, the argument implies nothing of the sort. That all electrons are indistinguishable—have identical properties—doesn’t mean they’re all numerically identical (another of that ‘addleheaded’ philosophical distinctions: numerical vs. qualitative identity). There can be 3,000 electrons in a pile, but you can’t stick numerical labels onto them—you can’t say, ‘that one is electron 1,679, and this one is electron 561’.
But the issue here is personal identity: that is, what makes you experience a continuous stream of conscious experiences. Or what makes it such that the you that wakes up tomorrow is the same as the you that went to bed the day before. There’s no consistent concept of identity anybody’s yet come up with that works for these cases, but excludes cases of Boltzmann brains and the like; there’s a vast literature on the topic you can peruse at liberty to get yourself up to speed.
Or, well, you can just stick to your own preconceived notions—whatever floats your boat!
Well, that’s really a bit strong. There are probably some concepts, perhaps four-dimensionalism or something, but most of them end up running quite counter to our intuitions; so it’d be better to say that it’s a lot harder to come up with a concept that recapitulates the intuitive notions of personal identity, but doesn’t include weird cases like quantum immortality and Boltzmann brains and stuff, than one might naively think.
I’m pretty sure the common concept of identity, which leans on multiple forms of continuity (most heavily on temporospatial continuity) and is explored in the Theseus’s ship paradox, handles sleep and excludes Boltzmann brains just fine.
This Boltzmann brain business is comparable to various transporter paradoxes, and I’ll arbitrarily construct one that exemplifies the issue: you step into a transporter and it scans you for transport - and then fails to destroy the version of you that is standing in the transporter, while still constructing a ‘new you’ out of different particles at the target location. So - is the new you the real you (rendering you…what?), or is the ‘new you’, despite his protests, a copy?
I say he’s a copy. And yes, I say that transporters clearly destroy the people they send - not that anybody who survives the process cares.
Well, but it’s easy to show such a concept doesn’t work: consider a statue and the clay it’s made of. Are they identical? They’re spatiotemporally continuous, so you’d probably claim so. But what of the claim that the statue is destroyed, if it is, say, rolled flat? The same isn’t true of the clay it consists of: that manifestly persists. But spatiotemporal continuity is preserved at any point.
Or what if you were put through a meat grinder? What comes out the other end is spatiotemporally continuous with you; but few would hold that it still is you—you as a person, that is. So one would have to add something to the definition—say, a certain arrangement: the statue is the clay, arranged statue-wise; thus, if the clay is no longer arranged in that particular way, it’s no longer the statue.
Moreover, then we can come in and question whether the clay actually has a hand at all in determining the statue’s identity. And that’s where the ship of Theseus comes in: you switch out the clay of the little finger, replacing it with new clay, and it clearly remains the same statue. And so on. So it’s clearly no single bit of clay on which the statue’s identity hinges—that identity can be divorced from any particular bit of clay you care to specify. On the other hand, change the arrangement—the form—and you’d quite quickly end up with something you’d no longer identify with the original statue. So the identity seems to much rather inhere in that arrangement than in the clay.
But the arrangement can obviously be shared by multiple objects. So if it’s the arrangement that makes the statue the statue, and you you, then what grounds do we have to say that some other matter arranged the same way doesn’t have the same claim to that identity? What role does spatiotemporal continuity actually play in the example? And there’s lots of people that hold there’s just no role left to play. And you’re not gonna get their arguments to go away with a wave of your hand. So if this is something of interest to you, then I’d suggest you’d try reading up on it—maybe start with the entry on identity in the Stanford Encyclopedia—and at least get some sort of an overview of the positions at issue, the arguments that have been advanced in their favor, counterarguments that have been made, any maybe, at some point, once you’ve gained some understanding of the matter, those philosophers won’t even seem quite that addleheaded anymore!
As noted, temporospatial continuity is merely the largest part of identity. However it’s such a big part of it that I’d say you’re wrong here - if somebody else walked up and said, “Hey, where’s the statue” then it’s quite likely that their response would be somebody pointing at the flattened clay and say, “right there”.
It’s not that the statue ceased to exist; it’s that it was changed into something else. Sort of how I’m no longer a slender teenager and am instead an old fat dude, but I’m still considered by pretty much everyone to be the same human due mostly to all that temporospatial continuity I’ve been packing around.
Once again: “(Munch, munch) Hmm, this hamburger is great. Oh, hey, where’s begbert2 got to?” “Guess.”
Let’s be serious here - there are a few different definitions of the word “identity”, including one where you can change it by taking off your spandex suit and cape and putting on a pair of glasses and a reporter’s badge. But the kind of identity that we’re talking about in this conversation has a much more forgiving relationship with changes to physical arrangement than you imply, and anybody who tells you otherwise is warming up to selling you a barrow full of bullshit.
That is very much NOT the correct conclusion to draw from the Theseus’s ship paradox, because it’s gratuitously, deliberately, and erroneously ‘overlooking’ the fact that a major part of the arrangement of bits being Theseus’s ship is that at all times the thing with the identity of “Theseus’s ship” is temporospatially continuous, regardless of the additions, removals, and changes. That paradox makes exactly the opposite point that you claim it does.
By your argument, if Fred admired Theseus’s ship a lot and made an exact copy of it, then Theseus could steal Fred’s Ship on the basis of it being the “same” ship as Theseus’s Ship and thus already his possession. Which is of course obviously, laughably wrong.
There’s lots of people who are dingbats and you’re right - I can’t make them stop blabbering nonsense by waving my hand. Philosophers get credit and fame for their radical ideas whether they’re coherent or not.
I’ve read far more philosophy than a person really ought to, and that doesn’t make all of them right or all of their arguments meritous. But sure, I can go read about identity again I guess.
No. The paradox is intended to highlight a puzzle regarding identity:
It is supposed that the famous ship sailed by the hero Theseus in a great battle was kept in a harbor as a museum piece, and as the years went by some of the wooden parts began to rot and were replaced by new ones; then, after a century or so, every part had been replaced. The question then is if the “restored” ship is still the same object as the original.
If it is, then suppose the removed pieces were stored in a warehouse, and after the century, technology was developed that cured their rot and enabled them to be reassembled into a ship? Is this “reconstructed” ship the original ship? If it is, then what about the restored ship in the harbor still being the original ship as well?
Right - the paradox raises the question of what constitutes identity and asks the user to consider it. Virtually every answer has some apparent downsides.
Of course, the approach “the identity of the object is any and everything that follows the blueprint” has nothing but downsides, and is arguably wrong even where it professes to be right - because the problem explicitly states that the replacement boards are not copies of the removed ones. Of the two resulting ships, one will be strong and new, and one will be rotting and dilapidated - and the new ship will have been a series of different partially-updated versions of itself over time. With so many completely differently-structured designs in play, there is no way to derive “any ship that is identical to the design of this ship is this ship” from this argument at all.
Which isn’t going to stop people from saying it, mind you. But it not going to be based on anything regarding the scenario under discussion.
To add a little bit to the Theseus’s Ship thing, I’m not sure the ‘blueprint’ thing actually factors into either ship’s claim to the title. The repaired ship claims the title based on continuity of existence - it is Theseus’s ship because it’s been Theseus’s ship the whole time. The new ship’s claim to the title is that its entirely composed of parts that once were part of Theseus’s ship. However I’m not sure any part of that claim is based on the parts being arranged in the same way as before. If some of the boards get swapped around that doesn’t matter, because it’s not Theseus’s ship because of the arrangement of the parts, it’s claiming that it’s Theseus’s ship because of where the parts came from. The new ship could be half as large and full of holes and its claim in that regard would be exactly the same.
Interestingly, that’s exactly how intellectual property works.
That’s because you don’t own the ship, you own the design of the ship. You then sell individual ships without selling the rights to the design.
Well so far I have no direct evidence that I’m not immortal…