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Timeless Identity

22 Post author: Eliezer_Yudkowsky 03 June 2008 08:16AM

Followup toNo Individual Particles, Identity Isn't In Specific Atoms, Timeless Physics, Timeless Causality

People have asked me, "What practical good does it do to discuss quantum physics or consciousness or zombies or personal identity?  I mean, what's the application for me in real life?"

Before the end of today's post, we shall see a real-world application with practical consequences, for you, yes, you in today's world.  It is built upon many prerequisites and deep foundations; you will not be able to tell others what you have seen, though you may (or may not) want desperately to tell them.  (Short of having them read the last several months of OB.)

In No Individual Particles we saw that the intuitive conception of reality as little billiard balls bopping around, is entirely and absolutely wrong; the basic ontological reality, to the best of anyone's present knowledge, is a joint configuration space.  These configurations have mathematical identities like "A particle here, a particle there", rather than "particle 1 here, particle 2 there" and the difference is experimentally testable.  What might appear to be a little billiard ball, like an electron caught in a trap, is actually a multiplicative factor in a wavefunction that happens to approximately factor.  The factorization of 18 includes two factors of 3, not one factor of 3, but this doesn't mean the two 3s have separate individual identities—quantum mechanics is sort of like that.  (If that didn't make any sense to you, sorry; you need to have followed the series on quantum physics.)

In Identity Isn't In Specific Atoms, we took this counterintuitive truth of physical ontology, and proceeded to kick hell out of an intuitive concept of personal identity that depends on being made of the "same atoms"—the intuition that you are the same person, if you are made out of the same pieces.  But because the brain doesn't repeat its exact state (let alone the whole universe), the joint configuration space which underlies you, is nonoverlapping from one fraction of a second to the next.  Or even from one Planck interval to the next.  I.e., "you" of now and "you" of one second later do not have in common any ontologically basic elements with a shared persistent identity.

Just from standard quantum mechanics, we can see immediately that some of the standard thought-experiments used to pump intuitions in philosophical discussions of identity, are physical nonsense.  For example, there is a thought experiment that runs like this:

"The Scanner here on Earth will destroy my brain and body, while recording the exact states of all my cells.  It will then transmit this information by radio.  Travelling at the speed of light, the message will take three minutes to reach the Replicator on Mars.  This will then create, out of new matter, a brain and body exactly like mine.  It will be in this body that I shall wake up."

This is Derek Parfit in the excellent Reasons and Persons, p. 199—note that Parfit is describing thought experiments, not necessarily endorsing them.

There is an argument which Parfit describes (but does not himself endorse), and which I have seen many people spontaneously invent, which says (not a quote):

Ah, but suppose an improved Scanner were invented, which scanned you non-destructively, but still transmitted the same information to Mars .  Now, clearly, in this case, you, the original have simply stayed on Earth, and the person on Mars is only a copy.  Therefore this teleporter is actually murder and birth, not travel at all—it destroys the original, and constructs a copy!

Well, but who says that if we build an exact copy of you, one version is the privileged original and the other is just a copy?  Are you under the impression that one of these bodies is constructed out of the original atoms—that it has some kind of physical continuity the other does not possess?  But there is no such thing as a particular atom, so the original-ness or new-ness  of the person can't depend on the original-ness or new-ness of the atoms.

(If you are now saying, "No, you can't distinguish two electrons yet, but that doesn't mean they're the same entity -" then you have not been following the series on quantum mechanics, or you need to reread it.  Physics does not work the way you think it does.  There are no little billiard balls bouncing around down there.)

If you further realize that, as a matter of fact, you are splitting all the time due to ordinary decoherence, then you are much more likely to look at this thought experiment and say:  "There is no copy; there are two originals."

Intuitively, in your imagination, it might seem that one billiard ball stays in the same place on Earth, and another billiard ball has popped into place on Mars; so one is the "original", and the other is the "copy".  But at a fundamental level, things are not made out of billiard balls.

A sentient brain constructed to atomic precision, and copied with atomic precision, could undergo a quantum evolution along with its "copy", such that, afterward, there would exist no fact of the matter as to which of the two brains was the "original".  In some Feynman diagrams they would exchange places, in some Feynman diagrams not.  The two entire brains would be, in aggregate, identical particles with no individual identities.

Parfit, having discussed the teleportation thought experiment, counters the intuitions of physical continuity with a different set of thought experiments:

"Consider another range of possible cases: the Physical Spectrum.  These cases involve all of the different possible degrees of physical continuity...

"In a case close to the near end, scientists would replace 1% of the cells in my brain and body with exact duplicates.  In the case in the middle of the spectrum, they would replace 50%.  In a case near the far end, they would replace 99%, leaving only 1% of my original brain and body.  At the far end, the 'replacement' would involve the complete destruction of my brain and body, and the creation out of new organic matter of a Replica of me."

(Reasons and Persons, p. 234.)

Parfit uses this to argue against the intuition of physical continuity pumped by the first experiment: if your identity depends on physical continuity, where is the exact threshold at which you cease to be "you"?

By the way, although I'm criticizing Parfit's reasoning here, I really liked Parfit's discussion of personal identity.  It really surprised me.  I was expecting a rehash of the same arguments I've seen on transhumanist mailing lists over the last decade or more.  Parfit gets much further than I've seen the mailing lists get.  This is a sad verdict for the mailing lists.  And as for Reasons and Persons, it well deserves its fame.

But although Parfit executed his arguments competently and with great philosophical skill, those two particular arguments (Parfit has lots more!) are doomed by physics.

There just is no such thing as "new organic matter" that has a persistent identity apart from "old organic matter".  No fact of the matter exists, as to which electron is which, in your body on Earth or your body on Mars.  No fact of the matter exists, as to how many electrons in your body have been "replaced" or "left in the same place".  So both thought experiments are physical nonsense.

Parfit seems to be enunciating his own opinion here (not Devil's advocating) when he says:

"There are two kinds of sameness, or identity.  I and my Replica are qualitatively identical, or exactly alike.  But we may not be numerically identical, one and the same person.  Similarly, two white billiard balls are not numerically but may be qualitatively identical.  If I paint one of these balls red, it will cease to be qualitatively identical with itself as it was.  But the red ball that I later see and the white ball that I painted red are numerically identical.  They are one and the same ball." (p. 201.)

In the human imagination, the way we have evolved to imagine things, we can imagine two qualitatively identical billiard balls that have a further fact about them—their persistent identity—that makes them distinct.

But it seems to be a basic lesson of physics that "numerical identity" just does not exist.  Where "qualitative identity" exists, you can set up quantum evolutions that refute the illusion of individuality—Feynman diagrams that sum over different permutations of the identicals.

We should always have been suspicious of "numerical identity", since it was not experimentally detectable; but physics swoops in and drop-kicks the whole argument out the window.

Parfit p. 241:

"Reductionists admit that there is a difference between numerical identity and exact similarity.  In some cases, there would be a real difference between some person's being me, and his being someone else who is merely exactly like me."

This reductionist admits no such thing.

Parfit even describes a wise-seeming reductionist refusal to answer questions as to when one person becomes another, when you are "replacing" the atoms inside them.  P. 235:

(The reductionist says:)  "The resulting person will be psychologically continuous with me as I am now.  This is all there is to know.  I do not know whether the resulting person will be me, or will be someone else who is merely exactly like me.  But this is not, here, a real question, which must have an answer.  It does not describe two different possibilities, one of which must be true.  It is here an empty question.  There is not a real difference here between the resulting person's being me, and his being someone else.  This is why, even though I do not know whether I am about to die, I know everything."

Almost but not quite reductionist enough!  When you master quantum mechanics, you see that, in the thought experiment where your atoms are being "replaced" in various quantities by "different" atoms, nothing whatsoever is actually happening—the thought experiment itself is physically empty.

So this reductionist, at least, triumphantly says—not, "It is an empty question; I know everything that there is to know, even though I don't know if I will live or die"—but simply, "I will live; nothing happened."

This whole episode is one of the main reasons why I hope that when I really understand matters such as these, and they have ceased to be mysteries unto me, that I will be able to give definite answers to questions that seem like they ought to have definite answers.

And it is a reason why I am suspicious, of philosophies that too early—before the dispelling of mystery—say, "There is no answer to the question."  Sometimes there is no answer, but then the absence of the answer comes with a shock of understanding, a click like thunder, that makes the question vanish in a puff of smoke.  As opposed to a dull empty sort of feeling, as of being told to shut up and stop asking questions.

And another lesson:  Though the thought experiment of having atoms "replaced" seems easy to imagine in the abstract, anyone knowing a fully detailed physical visualization would have immediately seen that the thought experiment was physical nonsense.  Let zombie theorists take note!

Additional physics can shift our view of identity even further:

In Timeless Physics, we looked at a speculative, but even more beautiful view of quantum mechanics:  We don't need to suppose the amplitude distribution over the configuration space is changing, since the universe never repeats itself.  We never see any particular joint configuration (of the whole universe) change amplitude from one time to another; from one time to another, the universe will have expanded.  There is just a timeless amplitude distribution (aka wavefunction) over a configuration space that includes compressed configurations of the universe (early times) and expanded configurations of the universe (later times).

Then we will need to discover people and their identities embodied within a timeless set of relations between configurations that never repeat themselves, and never change from one time to another.

As we saw in Timeless Beauty, timeless physics is beautiful because it would make everything that exists either perfectly global—like the uniform, exceptionless laws of physics that apply everywhere and everywhen—or perfectly local—like points in the configuration space that only affect or are affected by their immediate local neighborhood.  Everything that exists fundamentally, would be qualitatively unique: there would never be two fundamental entities that have the same properties but are not the same entity.

(Note:  The you on Earth, and the you on Mars, are not ontologically basic.  You are factors of a joint amplitude distribution that is ontologically basic.  Suppose the integer 18 exists: the factorization of 18 will include two factors of 3, not one factor of 3.  This does not mean that inside the Platonic integer 18 there are two little 3s hanging around with persistent identities, living in different houses.)

We also saw in Timeless Causality that the end of time is not necessarily the end of cause and effect; causality can be defined (and detected statistically!) without mentioning "time".  This is important because it preserves arguments about personal identity that rely on causal continuity rather than "physical continuity".

Previously I drew this diagram of you in a timeless, branching universe:

Manybranches4

To understand many-worlds:  The gold head only remembers the green heads, creating the illusion of a unique line through time, and the intuitive question, "Where does the line go next?"  But it goes to both possible futures, and both possible futures will look back and see a single line through time.  In many-worlds, there is no fact of the matter as to which future you personally will end up in.  There is no copy; there are two originals.

To understand timeless physics:  The heads are not popping in and out of existence as some Global Now sweeps forward.  They are all just there, each thinking that now is a different time.

In Timeless Causality I drew this diagram:

Causeright

This was part of an illustration of how we could statistically distinguish left-flowing causality from right-flowing causality—an argument that cause and effect could be defined relationally, even the absence of a changing global time.  And I said that, because we could keep cause and effect as the glue that binds configurations together, we could go on trying to identify experiences with computations embodied in flows of amplitude, rather than having to identify experiences with individual configurations.

But both diagrams have a common flaw: they show discrete nodes, connected by discrete arrows.  In reality, physics is continuous.

So if you want to know "Where is the computation?  Where is the experience?" my best guess would be to point to something like a directional braid:

Braid_2

This is not a braid of moving particles.  This is a braid of interactions within close neighborhoods of timeless configuration space.

Braidslice

Every point intersected by the red line is unique as a mathematical entity; the points are not moving from one time to another.  However, the amplitude at different points is related by physical laws; and there is a direction of causality to the relations.

You could say that the amplitude is flowing, in a river that never changes, but has a direction.

Embodied in this timeless flow are computations; within the computations, experiences.  The experiences' computations' configurations might even overlap each other:

Braidtime_2

In the causal relations covered by the rectangle 1, there would be one moment of Now; in the causal relations covered by the rectangle 2, another moment of Now.  There is a causal direction between them: 1 is the cause of 2, not the other way around.  The rectangles overlap—though I really am not sure if I should be drawing them with overlap or not—because the computations are embodied in some of the same configurations.  Or if not, there is still causal continuity because the end state of one computation is the start state of another.

But on an ontologically fundamental level, nothing with a persistent identity moves through time.

Even the braid itself is not ontologically fundamental; a human brain is a factor of a larger wavefunction that happens to factorize.

Then what is preserved from one time to another?  On an ontologically basic level, absolutely nothing.

But you will recall that I earlier talked about any perturbation which does not disturb your internal narrative, almost certainly not being able to disturb whatever is the true cause of your saying "I think therefore I am"—this is why you can't leave a person physically unaltered, and subtract their consciousness.  When you look at a person on the level of organization of neurons firing, anything which does not disturb, or only infinitesimally disturbs, the pattern of neurons firing—such as flipping a switch from across the room—ought not to disturb your consciousness, or your personal identity.

If you were to describe the brain on the level of neurons and synapses, then this description of the factor of the wavefunction that is your brain, would have a very great deal in common, across different cross-sections of the braid.  The pattern of synapses would be "almost the same"—that is, the description would come out almost the same—even though, on an ontologically basic level, nothing that exists fundamentally is held in common between them.  The internal narrative goes on, and you can see it within the vastly higher-level view of the firing patterns in the connection of synapses.  The computational pattern computes, "I think therefore I am".  The narrative says, today and tomorrow, "I am Eliezer Yudkowsky, I am a rationalist, and I have something to protect."  Even though, in the river that never flows, not a single drop of water is shared between one time and another.

If there's any basis whatsoever to this notion of "continuity of consciousness"—I haven't quite given up on it yet, because I don't have anything better to cling to—then I would guess that this is how it works.

Oh... and I promised you a real-world application, didn't I?

Well, here it is:

Many throughout time, tempted by the promise of immortality, have consumed strange and often fatal elixirs; they have tried to bargain with devils that failed to appear; and done many other silly things.

But like all superpowers, long-range life extension can only be acquired by seeing, with a shock, that some way of getting it is perfectly normal.

If you can see the moments of now braided into time, the causal dependencies of future states on past states, the high-level pattern of synapses and the internal narrative as a computation within it—if you can viscerally dispel the classical hallucination of a little billiard ball that is you, and see your nows strung out in the river that never flows—then you can see that signing up for cryonics, being vitrified in liquid nitrogen when you die, and having your brain nanotechnologically reconstructed fifty years later, is actually less of a change than going to sleep, dreaming, and forgetting your dreams when you wake up.

You should be able to see that, now, if you've followed through this whole series.  You should be able to get it on a gut level—that being vitrified in liquid nitrogen for fifty years (around 3e52 Planck intervals) is not very different from waiting an average of 2e26 Planck intervals between neurons firing, on the generous assumption that there are a hundred trillion synapses firing a thousand times per second.  You should be able to see that there is nothing preserved from one night's sleep to the morning's waking, which cryonic suspension does not preserve also.  Assuming the vitrification technology is good enough for a sufficiently powerful Bayesian superintelligence to look at your frozen brain, and figure out "who you were" to the same resolution that your morning's waking self resembles the person who went to sleep that night.

Do you know what it takes to securely erase a computer's hard drive?  Writing it over with all zeroes isn't enough.  Writing it over with all zeroes, then all ones, then a random pattern, isn't enough.  Someone with the right tools can still examine the final state of a section of magnetic memory, and distinguish the state, "This was a 1 written over by a 1, then a 0, then a 1" from "This was a 0 written over by a 1, then a 0, then a 1".  The best way to securely erase a computer's hard drive is to destroy it with thermite.

I really don't think that carefully vitrifying a brain to prevent ice crystal formation and then freezing it in liquid nitrogen is going to be a secure erase procedure, if you can examine atomic-level differences in the synapses.

Someone hears about cryonics and thinks for 10 seconds and says, "But if you're frozen and then revived, are you really the same person?"

And if they happened to know all about quantum physics and could apply the abstract knowledge to real life, and they had followed the whole debate about zombies and resolved it against epiphenomenalism in general, then they would be able to visualize the braids in the river that never flows, and say, "Yes."

But this knowledge is not common.

So they die.

There are numerous other reasons that people seize on, when they search for a rationalization for a negative initial flinch against cryonics.  And numerous other knowledges that would be required to answer those objections.  "But wouldn't it be boring to live such a long time?"  (Can be answered if you know hedonic psychology, and have developed a theory of fun, and can visualize accessible fun spaces that increase in volume with increasing intelligence.)  "Why would future civilizations bother to revive me?"  (Requires understanding either economic growth diminishing the cost, or knowledge of history and how societies have become kinder over time, or knowing about Friendly AI.)  "Isn't it wrong to live so long?"  (Requires knowing about the "sour grapes" bias.  See also transhumanism as simplified humanism and the meaning that immortality gives to life.)  Then there's the meta-knowledge of how to question all these deeply wise cached thoughts that pop into your head about the futility of life; and the ability to do things that might make people look at you weird, and so on...

Some of these are series of posts I haven't done yet.  But if you anticipate updating your probabilities when you read those future posts, then you should update them now.  Or, if you prefer, trust me:

If you would rather live happily ever after, than die, and you are willing to spend between $300 and $2000 per year(*) to express this preference, then sign up for cryonics.

If you've been cryocrastinating, putting off signing up for cryonics "until later", don't think that you've "gotten away with it so far".  Many worlds, remember?  There are branched versions of you that are dying of cancer, and not signed up for cryonics, and it's too late for them to get life insurance.

See, knowing about many worlds can help you visualize probabilities as frequencies, because they usually are.

It might encourage you to get around to getting health insurance, too, or wearing a helmet on your motorcycle, or whatever: don't think you've gotten away with it so far.

And if you're planning to play the lottery, don't think you might win this time.  A vanishingly small fraction of you wins, every time.  So either learn to discount small fractions of the future by shutting up and multiplying, or spend all your money on lottery tickets—your call.

It is a very important lesson in rationality, that at any time, the Environment may suddenly ask you almost any question, which requires you to draw on 7 different fields of knowledge.  If you missed studying a single one of them, you may suffer arbitrarily large penalties up to and including capital punishment.  You can die for an answer you gave in 10 seconds, without realizing that a field of knowledge existed of which you were ignorant.

This is why there is a virtue of scholarship.

150,000 people die every day.  Some of those deaths are truly unavoidable, but most are the result of inadequate knowledge of cognitive biases, advanced futurism, and quantum mechanics.(**)

If you disagree with my premises or my conclusion, take a moment to consider nonetheless, that the very existence of an argument about life-or-death stakes, whatever position you take in that argument, constitutes a sufficient lesson on the sudden relevance of scholarship.


(*)  The way cryonics works is that you get a life insurance policy, and the policy pays for your cryonic suspension.  The Cryonics Institute is the cheapest provider, Alcor is the high-class one.  Rudi Hoffman set up my own insurance policy, with CI.  I have no affiliate agreements with any of these entities, nor, to my knowledge, do they have affiliate agreements with anyone.  They're trying to look respectable, and so they rely on altruism and word-of-mouth to grow, instead of paid salespeople.  So there's a vastly smaller worldwide market for immortality than lung-cancer-in-a-stick.  Welcome to your Earth; it's going to stay this way until you fix it.

(**)  Most deaths?  Yes:  If cryonics were widely seen in the same terms as any other medical procedure, economies of scale would considerably diminish the cost; it would be applied routinely in hospitals; and foreign aid would enable it to be applied even in poor countries.  So children in Africa are dying because citizens and politicians and philanthropists in the First World don't have a gut-level understanding of quantum mechanics.

Added:  For some of the questions that are being asked, see Alcor's FAQ for scientists and Ben Best's Cryonics FAQ (archived snapshot).

 

Part of The Quantum Physics Sequence

Next post: "Thou Art Physics"

Previous post: "Timeless Causality"

Comments (233)

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Comment author: Roland2 03 June 2008 09:03:28AM 8 points [-]

Where can I sign up for cryonics if I live outside the United States and Europe?

Comment author: TimFreeman 19 April 2011 05:11:08PM 7 points [-]

Kriorus might be worth a try.

Be aware that some jurisdictions, such as British Columbia and France, go out of their way to outlaw it.

Comment author: mitchell_porter2 03 June 2008 09:23:53AM 5 points [-]

The argument that "there is no such thing as a particular atom, therefore neither duplicate has a preferred status as the original" looks sophistical, and it may even be possible to show that it is within your preferred quantum framework. Consider a benzene ring. That's a ring of six carbon atoms. If it occurs as part of a larger molecule, there will be covalent bonds between particular atoms in the ring and atoms exterior to it. Now suppose I verify the presence of the benzene ring through some nondestructive procedure, and then create another benzene ring elsewhere, using other atoms. In fact, suppose I have a machine which will create that second benzene ring only if the investigative procedure verifies the existence of the first. I have created a copy, but are you really going to say there's no fact of the matter about which is the original? There's even a hint of how you can distinguish between the two given your ontological framework, when I stipulated that the original ring is bonded to something else; something not true of the duplicate. If you insist on thinking there is no continuity of identity of individual particles, at least you can say that one of the carbon atoms in the first ring is entangled with an outside atom in a way that none of the atoms in the duplicate ring is, and distinguish between them that way. You may be able to individuate atoms within structures by looking at their quantum correlations; you won't be able to say 'this atom has property X, that atom has property Y' but you'll be able to say 'there's an atom with property X, and there's an atom with property Y'.

Assuming that this is on the right track, the deeper reality is going to be field configurations anyway, not particle configurations. Particle number is frame-dependent (see: Unruh effect), and a quantum particle is just a sort of wavefunction over field configurations - a blob of amplitude in field configuration space.

Comment author: Eliezer_Yudkowsky 03 June 2008 09:30:59AM 2 points [-]

Roland, I do not know. There is an organization in Russia. The Cryonics Institute accepts bodies shipped to them packed in ice. I'm not sure about Alcor, which tries to do on-scene suspension. Alcor lists a $25K surcharge (which would be paid out of life insurance) for suspension outside the US/UK/Canada, but I'm not sure how far abroad they'd go. Where are you?

Mitchell: You may be able to individuate atoms within structures by looking at their quantum correlations; you won't be able to say 'this atom has property X, that atom has property Y' but you'll be able to say 'there's an atom with property X, and there's an atom with property Y'.

Certainly. That's how we distinguish Eliezer from Mitchell.

Comment author: someonewrongonthenet 15 August 2012 07:21:23PM *  2 points [-]

Eliezer...the main issue that keeps me from cryonics is not whether the "real me" wakes up on the other side.

The first question is about how accurate the reconstruction will be. When you wipe a hard drive with a magnet, you can recover some of the content, but usually not all of it. Recovering "some" of a human, but not all of it, could easily create a mentally handicapped, broken consciousness.

But lets set that aside, as it is a technical problem. There is an second issue. If and when immortality and AI are achieved, what value would my revived consciousness contribute to such a society?

You've thus far established that death isn't a bad thing when a copy of the information is preserved and later revived. You've explained that you are willing to treat consciousness much like you would a computer file - you've explained that you would be willing to destroy one of two redundant duplicates of yourself.

Tell me, why exactly is it okay to destroy a redundant duplicate of yourself? You can't say that it's okay to destroy it simply because it is redundant, because that also destroys the point of cryonics. There will be countless humans and AIs that will come into existence, and each of those minds will require resources to maintain. Why is it so important that your, or my, consciousness be one among this swarm? Is that not similarly redundant?

For the same reasons that you would be willing to destroy one of two identical copies of yourself because having two copies is redundant, I am wondering just how much I care that my own consciousness survives forever. My mind is not exceptional among all the possible consciousnesses that resources could be devoted to. Keeping my mind preserved through the ages seems to me just as redundant as making twenty copies of yourself and carefully preserving each one.

I'm not saying I don't want to live forever...I do want to. I'm saying that I feel one aught to have a reason for preserving ones consciousness that goes beyond the simple desire for at least one copy of ones consciousness to continue existing.

When we deconstruct the notion of consciousness as thoroughly as we are doing in this discussion, the concept of "life" and "death" become meaningless over-approximations, much like "free will". Once society reaches that point, we are going to have to deconstruct those ideas and ask ourselves why it is so important that certain information never be deleted. Otherwise, it's going to get a little silly...a "21st century human brain maximizer" is not that much different from a paperclip maximizer, in the grand scheme of things.

Comment author: Mark_Friedenbach 30 September 2013 04:21:55PM 0 points [-]

The main issue that keeps me from cryonics is not whether the "real me" wakes up on the other side.

How do you go to sleep at night, not knowing if it is the "real you" that wakes up on the other side of consciousness?

Comment author: TheOtherDave 30 September 2013 05:32:15PM 1 point [-]

Your comment would make more sense to me if I removed the word "not" from the sentence you quote. (Also, if I don't read past that sentence of someonewrongonthenet's comment.)

That said, I agree completely that the kinds of vague identity concerns about cryonics that the quoted sentence with "not" removed would be raising would also arise, were one consistent, about routine continuation of existence over time.

Comment author: Mark_Friedenbach 30 September 2013 06:37:14PM 0 points [-]

Hrm.. ambiguous semantics. I took it to imply acceptance of the idea but not elevation of its importance, but I see how it could be interpreted differently. And yes, the rest of the post addresses something completely different. But if I can continue for a moment on the tangent, expanding my comment above (even if it doesn't apply to the OP):

You actually continue functioning when you sleep, it's just that you don't remember details once you wake up. A more useful example for such discussion is general anesthesia, which shuts down the regions of the brain associated with consciousness. If personal identity is in fact derived from continuity of computation, then it is plausible that general anesthesia would result in a "different you" waking up after the operation. The application to cryonics depends greatly on the subtle distinction of whether vitrification (and more importantly, the recovery process) slows downs or stops computation. This has been a source of philosophical angst for me personally, but I'm still a cryonics member.

More troubling is the application to uploading. I haven't done this yet, but I want my Alcor contract to explicitly forbid uploading as a restoration process, because I am unconvinced that a simulation of my destructively scanned frozen brain would really be a continuation of my personal identity. I was hoping that “Timeless Identity” would address this point, but sadly it punts the issue.

Comment author: TheOtherDave 30 September 2013 07:01:54PM 3 points [-]

Well, if the idea is unimportant to the OP, presumably that also helps explain how they can sleep at night.

WRT the tangent... my own position wrt preservation of personal identity is that while it's difficult to articulate precisely what it is that I want to preserve, and I'm not entirely certain there is anything cogent I want to preserve that is uniquely associated with me, I'm pretty sure that whatever does fall in that category has nothing to do with either continuity of computation or similarity of physical substrate. I'm about as sanguine about continuing my existence as a software upload as I am about continuing it as this biological system or as an entirely different biological system, as long as my subjective experience in each case is not traumatically different.

Comment author: Mark_Friedenbach 01 October 2013 05:03:19PM 0 points [-]

I wrote up about a page-long reply, then realized it probably deserves its own posting. I'll see if I can get to that in the next day or so. There's a wide spectrum of possible solutions to the personal identity problem, from physical continuity (falsified) to pattern continuity and causal continuity (described by Eliezer in the OP), to computational continuity (my own view, I think). It's not a minor point though, whichever view turns out to be correct has immense ramifications for morality and timeless decision theory, among other things...

Comment author: TheOtherDave 01 October 2013 05:08:09PM 1 point [-]

When you write up the post, you might want to say a few words about what it means for one of these views to be "correct" or "incorrect."

Comment author: Mark_Friedenbach 01 October 2013 05:58:35PM 0 points [-]

Ok I will, but that part is easy enough to state here: I mean correct in the reductionist sense. The simplest explanation which resolves the original question and/or associated confusion, while adding to our predictive capacity and not introducing new confusion.

Comment author: TheOtherDave 01 October 2013 06:56:39PM *  2 points [-]

Mm. I'm not sure I understood that properly; let me echo my understanding of your view back to you and see if I got it.

Suppose I get in something that is billed as a transporter, but which does not preserve computational continuity. Suppose, for example, that it destructively scans my body, sends the information to the destination (a process which is not instantaneous, and during which no computation can take place), and reconstructs an identical body using that information out of local raw materials at my destination.

If it turns out that computational or physical continuity is the correct answer to what preserves personal identity, then I in fact never arrive at my destination, although the thing that gets constructed at the destination (falsely) believes that it's me, knows what I know, etc. This is, as you say, an issue of great moral concern... I have been destroyed, this new person is unfairly given credit for my accomplishments and penalized for my errors, and in general we've just screwed up big time.

Conversely, if it turns out that pattern or causal continuity is the correct answer, then there's no problem.

Therefore it's important to discover which of those facts is true of the world.

Yes? This follows from your view? (If not, I apologize; I don't mean to put up strawmen, I'm genuinely misunderstanding.)

If so, your view is also that if we want to know whether that's the case or not, we should look for the simplest answer to the question "what does my personal identity comprise?" that does not introduce new confusion and which adds to our predictive capacity. (What is there to predict here?)

Yes?

EDIT: Ah, I just read this post where you say pretty much this. OK, cool; I understand your position.

Comment author: pengvado 01 October 2013 06:09:33PM 2 points [-]

What relevance does personal identity have to TDT? TDT doesn't depend on whether the other instances of TDT are in copies of you, or in other people who merely use the same decision theory as you.

Comment author: Mark_Friedenbach 01 October 2013 06:33:08PM 0 points [-]

It has relevance for the basilisk scenario, which I'm not sure I should say any more about.

Comment author: shminux 30 September 2013 11:00:59PM *  1 point [-]

I want my Alcor contract to explicitly forbid uploading as a restoration process, because I am unconvinced that a simulation of my destructively scanned frozen brain would really be a continuation of my personal identity.

Like TheOtherDave (I presume), I consider my identity to be adequately described by whatever Turing machine that can emulate my brain, or at least its prefrontal cortex + relevant memory storage. I suspect that a faithful simulation of just my Brodmann area 10 coupled with a large chunk of my memories would restore enough of my self-awareness to be considered "me". This sim-me would probably lose most of my emotions without the rest of the brain, but it is still infinitely better than none.

Comment author: TheOtherDave 01 October 2013 12:12:21AM 0 points [-]

Like TheOtherDave (I presume), I consider my identity to be adequately described by whatever Turing machine that can emulate my brain, or at least its prefrontal cortex + relevant memory storage.

There's a very wide range of possible minds I consider to preserve my identity; I'm not sure the majority of those emulate my prefrontal cortex significantly more closely than they emulate yours, and the majority of my memories are not shared by the majority of those minds.

Comment author: shminux 01 October 2013 12:53:14AM 0 points [-]

Interesting. I wonder what you would consider a mind that preserves your identity. For example, I assume that the total of your posts online, plus whatever other information available without some hypothetical future brain scanner, all running as a process on some simulator, is probably not enough.

Comment author: TheOtherDave 01 October 2013 02:18:51AM 0 points [-]

At one extreme, if I assume those posts are being used to create a me-simulation by me-simulation-creator that literally knows nothing else about humans, then I'm pretty confident that the result is nothing I would identify with. (I'm also pretty sure this scenario is internally inconsistent.)

At another extreme, if I assume the me-simulation-creator has access to a standard template for my general demographic and is just looking to customize that template sufficiently to pick out some subset of the volume of mindspace my sufficiently preserved identity defines... then maybe. I'd have to think a lot harder about what information is in my online posts and what information would plausibly be in such a template to even express a confidence interval about that.

That said, I'm certainly not comfortable treating the result of that process as preserving "me."

Then again I'm also not comfortable treating the result of living a thousand years as preserving "me."

Comment author: someonewrongonthenet 01 October 2013 03:03:07AM *  0 points [-]

a large chunk of my memories

You'll need the rest of the brain because these other memories would be distributed throughout the rest of your cortex. The hippocampus only contains recent episodic memories.

If you lost your temporal lobe, for example, you'd lose all non-episodic knowledge concerning what the names of things are, how they are categorized, and what the relationships between them are.

Comment author: TheOtherDave 01 October 2013 03:07:43AM 0 points [-]

That said, I'm not sure why I should care much about having my non-episodic knowledge replaced with an off-the-shelf encyclopedia module. I don't identify with it much.

Comment author: someonewrongonthenet 01 October 2013 03:30:51AM *  0 points [-]

If you only kept the hippocampus, you'd lose your non-recent episodic memories too. But technical issues aside, let me defend the "encyclopedia":

Episodic memory is basically a cassette reel of your life, along with a few personalized associations and maybe memories of thoughts and emotions. Everything that we associate with the word knowledge is non-episodic. It's not just verbal labels - that was just a handy example that I happened to know the brain region for. I'd actually care about that stuff more about non-episodic memories than the episodic stuff.

Things like "what is your wife's name and what does her face look like" are non-episodic memory. You don't have to think back to a time when you specifically saw your wife to remember what her name and face is, and that you love her - that information is treated as a fact independent of any specific memory, indelibly etched into your model of the world. Cognitively speaking, "I love my wife stacy, she looks like this" is as much of a fact as "grass is a green plant" and they are both non-episodic memories. Your episodic memory reel wouldn't even make sense without that sort of information. I'd still identify someone with memory loss, but retaining my non-episodic memory, as me. I'd identify someone with only my episodic memories as someone else, looking at a reel of memory that does not belong to them and means nothing to them.

(Trigger Warning: link contains writing in diary which is sad, horrifying, and nonfiction.): This is what complete episodic memory loss looks like. Patients like this can still remember the names of faces of people they love.

Ironically...the (area 10) might actually be replaceable. I'm not sure whether any personalized memories are kept there - I don't know what that specific region does but it's in an area that mostly deals with executive function - which is important for personality, but not necessarily individuality.

Comment author: TheOtherDave 01 October 2013 03:46:42AM 0 points [-]

I take it you're assuming that information about my husband, and about my relationship to my husband, isn't in the encyclopedia module along with information about mice and omelettes and your relationship to your wife.

If that's true, then sure, I'd prefer not to lose that information.

Comment author: shminux 01 October 2013 06:28:16AM 0 points [-]

Ironically...the (area 10) might actually be replaceable. I'm not sure whether any personalized memories are kept there - I don't know what that specific region does but it's in an area that mostly deals with executive function - which is important for personality, but not necessarily individuality.

What's the difference between personality and individuality?

Comment author: army1987 01 October 2013 12:14:43AM *  0 points [-]

That said, I agree completely that the kinds of vague identity concerns about cryonics that the quoted sentence with "not" removed would be raising would also arise, were one consistent, about routine continuation of existence over time.

There are things that when I go to bed to wake up eight hours later are very nearly preserved but if I woke up sixty years later wouldn't be, e.g. other people's memories of me (see I Am a Strange Loop) or the culture of the place where I live (see Good Bye, Lenin!).

(I'm not saying whether this is one of the main reasons why I'm not signed up for cryonics.)

Comment author: TheOtherDave 01 October 2013 01:48:07AM 0 points [-]

Point.

Comment author: someonewrongonthenet 01 October 2013 02:51:03AM *  0 points [-]

Because the notion of "me" is not an ontologically basic category and the question of whether the "real me" wakes up is a question that aught to be un-asked.

I'm a bit confused at the question...you articulated my intent with that sentence perfectly in your other post.

Hrm.. ambiguous semantics. I took it to imply acceptance of the idea but not elevation of its importance, but I see how it could be interpreted differently.

and, as TheOtherDave said,

presumably that also helps explain how they can sleep at night.

EDIT: Nevermind, I now understand which part of my statement you misunderstood.

I'm not accepting-but-not-elevating the idea that the 'Real me" doesn't wake up on the other side. Rather, I'm saying that the questions of personal identity over time do not make sense in the first place. It's like asking "which color is the most moist"?

You actually continue functioning when you sleep, it's just that you don't remember details once you wake up. A more useful example for such discussion is general anesthesia, which shuts down the regions of the brain associated with consciousness. If personal identity is in fact derived from continuity of computation, then it is plausible that general anesthesia would result in a "different you" waking up after the operation. The application to cryonics depends greatly on the subtle distinction of whether vitrification (and more importantly, the recovery process) slows downs or stops computation. This has been a source of philosophical angst for me personally, but I'm still a cryonics member.

More troubling is the application to uploading. I haven't done this yet, but I want my Alcor contract to explicitly forbid uploading as a restoration process, because I am unconvinced that a simulation of my destructively scanned frozen brain would really be a continuation of my personal identity. I was hoping that “Timeless Identity” would address this point, but sadly it punts the issue.

The root of your philosophical dilemma is that "personal identity" is a conceptual substitution for soul - a subjective thread that connects you over space and time.

No such thing exists. There is no specific location in your brain which is you. There is no specific time point which is you. Subjective experience exists only in the fleeting present. The only "thread' connecting you to your past experiences is your current subjective experience of remembering them. That's all.

Comment author: Mark_Friedenbach 01 October 2013 05:15:55PM 0 points [-]

The root of your philosophical dilemma is that "personal identity" is a conceptual substitution for soul - a subjective thread that connects you over space and time.

No such thing exists. There is no specific location in your brain which is you. There is no specific time point which is you. Subjective experience exists only in the fleeting present. The only "thread' connecting you to your past experiences is your current subjective experience of remembering them. That's all.

I have a strong subjective experience of moment-to-moment continuity, even if only in the fleeting present. Simply saying “no such thing exists” doesn't do anything to resolve the underlying confusion. If no such thing as personal identity exists, then why do I experience it? What is the underlying insight that eliminates the question?

This is not an abstract question either. It has huge implications for the construction of timeless decision theory and utilitarian metamorality.

Comment author: shminux 01 October 2013 05:24:29PM *  0 points [-]

"a strong subjective experience of moment-to-moment continuity" is an artifact of the algorithm your brain implements. It certainly exists in as much as the algorithm itself exists. So does your personal identity. If in the future it becomes possible to run the same algorithm on a different hardware, it will still produce this sense of personal identity and will feel like "you" from the inside.

Comment author: Mark_Friedenbach 01 October 2013 05:53:06PM *  0 points [-]

Yes, I'm not questioning whether a future simulation / emulation of me would have an identical subjective experience. To reject that would be a retreat to epiphenomenalism.

Let me rephrase the question, so as to expose the problem: if I were to use advanced technology to have my brain scanned today, then got hit by a bus and cremated, and then 50 years from now that brain scan is used to emulate me, what would my subjective experience be today? Do I experience “HONK Screeeech, bam” then wake up in a computer, or is it “HONK Screeeech, bam” and oblivion?

Yes, I realize that in both cases result in a computer simulation of Mark in 2063 claiming to have just woken up in the brain scanner, with a subjective feeling of continuity. But is that belief true? In the two situations there's a very different outcome for the Mark of 2013. If you can't see that, then I think we are talking about different things, and maybe we should taboo the phrase “personal/subjective identity”.

Comment author: shminux 01 October 2013 06:32:09PM *  1 point [-]

if I were to use advanced technology to have my brain scanned today, then got hit by a bus and cremated, and then 50 years from now that brain scan is used to emulate me, what would my subjective experience be today? Do I experience “HONK Screeeech, bam” then wake up in a computer, or is it “HONK Screeeech, bam” and oblivion?

Ah, hopefully I'm slowly getting what you mean. So, there was the original you, Mark 2013, whose algorithm was terminated soon after it processed the inputs “HONK Screeeech, bam”, and the new you, Mark 2063, whose experience is “HONK Screeeech, bam” then "wake up in a computer". You are concerned with... I'm having trouble articulated what exactly... something about the lack of experiences of Mark 2013? But, say, if Mark 2013 was restored to life in mostly the same physical body after a 50-year "oblivion", you wouldn't be?

Comment author: Mark_Friedenbach 01 October 2013 06:55:52PM *  0 points [-]

Ah, hopefully I'm slowly getting what you mean. So, there was the original you, Mark 2013, whose algorithm was terminated soon after it processed the inputs “HONK Screeeech, bam”, and the new you, Mark 2063, whose experience is “HONK Screeeech, bam” then "wake up in a computer".

Pretty much correct. To be specific, if computational continuity is what matters, then Mark!2063 has my memories, but was in fact “born” the moment the simulation started, 50 years in the future. That's when his identity began, whereas mine ended when I died in 2013.

This seems a little more intuitive when you consider switching on 100 different emulations of me at the same time. Did I somehow split into 100 different persons? Or was there in fact 101 separate subjective identities, 1 of which terminated in 2013 and 100 new ones created for the simulations? The latter is a more straight forward explanation, IMHO.

You are concerned with... I'm having trouble articulated what exactly... something about the lack of experiences of Mark 2013? But, say, if Mark 2013 was restored to life in mostly the same physical body after a 50-year "oblivion", you wouldn't be?

No, that would make little difference as it's pretty clear that physical continuity is an illusion. If pattern or causal continuity were correct, then it'd be fine, but both theories introduce other problems. If computational continuity is correct, then a reconstructed brain wouldn't be me any more than a simulation would. However it's possible that my cryogenically vitrified brain would preserve identity, if it were slowly brought back online without interruption.

I'd have to learn more about how general anesthesia works to decide if personal identity would be preserved across on the operating table (until then, it scares the crap out of me). Likewise, a AI or emulation running on a computer that is powered off and then later resumed would also break identity, but depending on the underlying nature of computation & subjective experience, task switching and online suspend/resume may or may not result in cycling identity.

I'll stop there because I'm trying to formulate all these thoughts into a longer post, or maybe a sequence of posts.

Comment author: TheOtherDave 01 October 2013 07:02:09PM 0 points [-]

Did I somehow split into 100 different persons? Or was there in fact 101 separate subjective identities, 1 of which terminated in 2013 and 100 new ones created for the simulations? The latter is a more straight forward explanation, IMHO.

I would say that yes, at T1 there's one of me, and at T2 there's 100 of me.
I don't see what makes "there's 101 of me, one of which terminated at T1" more straightforward than that.

Comment author: lavalamp 01 October 2013 07:13:06PM 2 points [-]

Can you taboo "personal identity"? I don't understand what important thing you could lose by going under general anesthesia.

Comment author: shminux 01 October 2013 08:13:50PM 0 points [-]

I'd have to learn more about how general anesthesia works to decide if personal identity would be preserved across on the operating table

Hmm, what about across dreamless sleep? Or fainting? Or falling and hitting your head and losing consciousness for an instant? Would these count as killing one person and creating another? And so be morally net-negative?

Comment author: TheOtherDave 01 October 2013 07:09:33PM *  0 points [-]

Clearly, your subjective experience today is HONK-screech-bam-oblivion, since all the subjective experiences that come after that don't happen today in this example... they happen 50 years later.

It is not in the least bit clear to me that this means those subjective experiences aren't your subjective experiences. You aren't some epiphenomenal entity that dissipates in the course of those 50 years and therefore isn't around to experience those experiences when they happen... whatever is having those subjective experiences, whenever it is having them, that's you.

maybe we should taboo the phrase “personal/subjective identity”.

Sounds like a fine plan, albeit a difficult one. Want to take a shot at it?

EDIT: Ah, you did so elsethread. Cool. Replied there.

Comment author: lavalamp 01 October 2013 07:17:20PM 0 points [-]

Do I experience “HONK Screeeech, bam” then wake up in a computer, or is it “HONK Screeeech, bam” and oblivion?

Non-running algorithms have no experiences, so the latter is not a possible outcome. I think this is perhaps an unspoken axiom here.

Comment author: Mark_Friedenbach 01 October 2013 07:25:01PM 1 point [-]

Non-running algorithms have no experiences, so the latter is not a possible outcome. I think this is perhaps an unspoken axiom here.

No disagreement here - that's what I meant by oblivion.

Comment author: lavalamp 01 October 2013 07:31:37PM 1 point [-]

OK, cool, but now I'm confused. If we're meaning the same thing, I don't understand how it can be a question-- "not running" isn't a thing an algorithm can experience; it's a logical impossibility.

Comment author: hairyfigment 30 September 2013 04:55:39PM 0 points [-]

It seems you place less value on your life than I do on mine. I'm glad we've reached agreement.

Comment author: someonewrongonthenet 01 October 2013 03:14:40AM *  0 points [-]

I agree, it's quite possible that someone might deconstruct "me" and "life" and "death" and "subjective experience" to the same extent that I have and still value never deleting certain information that is computationally descended from themselves more than all the other things that would be done with the resources that are used to maintain them.

Hell, I might value it to that extent. This isn't something I'm certain about. I'm still exploring this. My default answer is to live forever - I just want to make sure that this is really what I want after consideration and not just a kicking, screaming survival instinct (AKA a first order preference)

Comment author: Frank_Hirsch 03 June 2008 09:32:58AM 2 points [-]

[Eliezer says:] And if you're planning to play the lottery, don't think you might win this time. A vanishingly small fraction of you wins, every time.

I think this is, strictly speaking, not true. A more extreme example: While recently talking with a friend, he asserted that "In one of the future worlds, I might jump up in a minute and run out onto the street, screaming loudly!". I said: "Yes, maybe, but only if you are already strongly predisposed to do so. MWI means that every possible future exists, not every arbitrary imaginable future.". Although your assertion in the case about lottery is much weaker, I don't believe it's strictly true.

Comment author: devicerandom 03 June 2008 09:38:58AM 2 points [-]

I have two (unrelated) comments:

1) I very much enjoyed the concept of "timeless physics", and in a MWI framework it sounds particularly elegant and intuitive. How does relativity fit into the picture? What I mean is, the speed of light, c, somehow gives an intrinsic measure of time to us. In what does c translates in timeless terms?

2) About your argument for cryonics, what about irreversible processes? Is quantum physics giving you a chance to beat entropy? When you die, a lot of irreversible processes happen into your brain (e.g. proteins and membranes break down). It is true that probably there are less changes in a cryonized brain than in a sleeping one, but it's the nature of the changes that's fundamently different. Of course no information is really lost, but it's irreversibly dispersed in the environment well before you have a chance to get it back. Cryonics to me looks like an attempt to unscramble an egg -only with the egg being frozen when it starts to scramble, but already a bit scrambled. I admit it is better than rotting in a grave (and I'd like to sign up for it) but has anyone tried to *measure* the hopes?

Comment author: Eliezer_Yudkowsky 03 June 2008 09:39:03AM 2 points [-]

Frank, it's not logically necessary but it seems highly likely to be true - the spread in worlds including "you" seems like it ought to include worlds where each combination of lottery balls turns up. Possibly even worlds where your friend screams and runs out of the room, though that might be a vanishingly small fraction unless predisposed.

Roland, the Cryonics Institute seems to accept patients from anywhere that can be arranged to be shipped: http://www.cryonics.org/euro.html. Not sure about Alcor.

Devicerandom, see the Added links to FAQs.

Comment author: mitchell_porter2 03 June 2008 09:47:00AM 0 points [-]

Eliezer: That's how we distinguish Eliezer from Mitchell.

Isn't that then how we distinguish a nondestructive copy from the original? If the original has been copied nondestructively, why shouldn't we continue to regard it as the original?

Comment author: Eliezer_Yudkowsky 03 June 2008 09:50:19AM 0 points [-]

Isn't that then how we distinguish a nondestructive copy from the original?

Not unless you postulate an imperfect copy, with covalent bonds in different places and so on.

Once you begin to postulate a theoretically imperfect copy, the Generalized version of the Anti-Zombie Principle has to take over and ask whether the differences have more impact on your internal narrative / memories / personality etc. than the corresponding effects of thermal noise at room temperature.

Comment author: mitchell_porter2 03 June 2008 10:01:57AM 2 points [-]

Covalent bonds with external atoms are just one form of "correlation with the environment".

I wish to postulate a perfect copy, in the sense that the internal correlations are identical to the original, but in which the correlations to the rest of the universe are different (e.g. "on Mars" rather than "on Earth").

There is some confusion here in the switching between individual configurations, and configuration space. An atom is already a blob in configuration space (e.g. "one electron in the ground-state orbital") rather than a single configuration, with respect to a particle basis.

While we cannot individuate particles in a relative configuration, we can individuate wave packets traveling in relative configuration space. And since even an atom already exists at that level, it is far from clear to me that the attempt to abandon continuity of identity carries over to complicated structures.

Comment author: MichaelAnissimov 03 June 2008 10:44:18AM 2 points [-]

Eliezer, why are *all* of your posts so long? I understand how most of them would be -- because you're trying to convey complex ideas -- but how come none of the ideas you convey are concise? Some of them seem like attempts to pad with excessive "background" material when simple tell-it-like-it-is brevity would suffice.

I thought this post was legitimately long, but this just came to mind when reflecting on past posts.

Comment author: Robin_Brandt 03 June 2008 11:10:21AM 2 points [-]

Great summary I have sent the link to all my friends! In the wait for some kind of TOC this is the best link yet to send people concerning this series.

I would like to know your opinion on Max Tegmarks ultimate ensemble theory! Or if someone knows Elis opinion on this wonderful theory, please tell me!

Are other bright scientists and philosophers aware of this blog? Do you send links to people when there is a topic that relates to them? Do you send links to the people you mention? Does Chalmers, Dennett, Pinker, Deutsch, Barbour, Pearl, Tegmark, Dawkins, Vinge, Egan, Hoftadter, McCarthy, Kurzweil, Smolin, Witten, Taleb, Shermer, Khaneman, Tooby, Cosmides, Aumann, Penrose, Hameroff etc. etc. know about all this?

They may all be wrong in one way or another, but they are certainly not stupid blind people.

And I think your writing would definitely interest all of these people and contribute to their work and journey towards the truth. So it would both be altruistic to send them the links, and exciting if they would comment!

Especially it would be nice if these people would comment on the posts where you show your dissagreement!

Comment author: IL 03 June 2008 11:32:12AM 2 points [-]

I *still* don't get the point of timeless physics. It seems to me like two different ways of looking at the same thing, like classical configuration space vs relational configuration space. Sure, it may make more sense to formulate the laws of physics without time, and it may make the equations much simpler, but how exactly does it change your expected observations? In what ways does a timeless universe differ from a timeful universe?

Also, I don't think it's neccessary to study quantum mechanics in order to understand personal identity. I've reached the same conclusions about identity without knowing anything about QM, I feel it's just simple deductions from materialism.

Comment author: Will_Pearson 03 June 2008 11:52:11AM 0 points [-]

The Rudi Hoffman link is broken.

Is there any literature on the likely energy costs of large scale cryonics?

And do you have a cunning plan where adding an extra 150k vitrified people per day to maintain does not drive up the already heaven ward bound energy prices, reducing the quality of life of the poorest? This could lead to conflict and more death, see recent South Africa for an example of poor energy planning.

A pre-requisite for large scale cryonics seem to me to be a stable and easily growable energy supply, which we just don't seem to be able to manage at the moment.

Comment author: Unknown 03 June 2008 12:34:46PM 6 points [-]

Eliezer, your account seems to give people two new excuses for not signing up for cryonics:

1) It seems to imply Quantum Immortality anyway.

2) Since there is nothing that persists on a fundamental level, the only reason new human beings in the future aren't "me" is that they don't remember me. But I also don't remember being two years old, and the two year old who became me didn't expect it. So the psychological continuity between my past self and my present self is no greater, in the case of my two year old self, than between myself and future human beings. This doesn't bother me in the case of the two year old, so it seems like it might not bother me in my own case. In other words, why should I try to live forever? There will be other human beings anyway, and they will be just as good as me, and there will be just as much identity on a fundamental level.

You may think that these arguments don't work, but that doesn't matter. The point is that because cryonics is "strange" to people, they are looking for reasons not to do it. So given that these arguments are plausible, they will embrace them immediately.

Comment author: Kaj_Sotala 03 June 2008 12:46:01PM 2 points [-]

Frank, it's not logically necessary but it seems highly likely to be true - the spread in worlds including "you" seems like it ought to include worlds where each combination of lottery balls turns up. Possibly even worlds where your friend screams and runs out of the room, though that might be a vanishingly small fraction unless predisposed.

Eliezer,

I have to ask now, because this is a topic that's been bothering me for months, and occasionally been making it real hard for me to take pleasure in anything.

How strongly does MWI imply that worlds will show up where I even do things that I consider immensly undesirable - for instance, stab somebody I love with a knife, and then when they lay there dying and look at me, I honestly can't tell them or myself why I did it - because what happened was caused by a very-low probability event that momentarily caused my brain to give my arm that command? (I know I'm not using anywhere near the correct QM terminology, but you know what I mean.) Or that my brain would spontaneously reconfigure parts of itself so that I ended up coldly abandoning somebody who had trusted me and who I'd promised to always be with, etc.

The thought of I - and yes, since there are no originals or copies, the very I writing this - having a guaranteed certainty of ending up doing that causes me so much anguish that I can't help but thinking that if true, humanity should be destroyed in order to minimize the amount of branches where people end up in such situations. I find little comfort in the prospect of the "betrayal branches" being vanishingly few in frequency - in absolute numbers, their amount is still unimaginably large, and more are born every moment.

Comment author: Ian_Maxwell 03 June 2008 01:52:08PM 1 point [-]

This argument makes no sense to me:

If you've been cryocrastinating, putting off signing up for cryonics "until later", don't think that you've "gotten away with it so far". Many worlds, remember? There are branched versions of you that are dying of cancer, and not signed up for cryonics, and it's too late for them to get life insurance.

This is only happening in the scenarios where I didn't sign up for cryonics. In the ones where I did sign up, I'm safe and cozy in my very cold bed. These universes don't exist contingent on my behavior in this one; what possible impact could my choice here to sign up for cryonics have on my alternate-universe Doppelg채ngeren?

Comment author: propater 08 March 2011 10:38:36AM *  1 point [-]

Same here. This does not strike me as a good argument at all... We can reverse it to argue against signing up for cryonics :

"Even if I sign up for cryonics, there will still be some other worlds in wich I didn't and in wich "I" am dying of cancer."

Or

"Even if don't sign up, there are still other worlds in wich I did."

Maybe there is something about me actually making the choice to sign up in this world altering/constraining the overall probability distribution and making some outcomes less and less probable in the overall distribution...

I am new to this side and I still have to search through it more thoroughfuly but I really don't think I can let that argument fly by without reaction. I appologize in advance if I make some really dumb mistake here.

Edit:

Okay, I thought this over a little bit and I can see a point: the earlier I sign up the more there will be of future "me"s getting cryonised. I do not see how much it matters in the grand scheme of things (I am just choosing a branch , I am not destroying the branch in wich I choose not to sign up.) but I guess there can be something along the lines of "I can not do much about the past but my decisions can influence the 'future'" or "my responsability is about my future 'me's, I should not worry about the worlds I can not 'reach'"

The argument still sounds rather weak to me (and the many-world view a bit nihilistic, not that it makes it wrong but I find it rather weird that you manage to get some sort of positive drive from it.)

Comment author: Luke_A_Somers 29 May 2012 03:20:08PM 1 point [-]

I am just choosing a branch , I am not destroying the branch in wich I choose not to sign up.

Actually... you are. The physical implementation of making the choice involves shifting weight from not-signed-up branches to signed-up branches (note, the 'not-signed-up-yet' branch is defined in a way that lets it leak amplitude). That implementation is contained within you, and it involves processes we describe as applying operators on that branch which reduce its amplitude. This totally counts as destroying the branch.

Comment author: Zaq 10 October 2013 09:58:04PM 0 points [-]

Okay, we need to be really careful about this.

If you sign up for cryonics at time T1, then the not-signed-up branch has lower amplitude after T1 than it had before T1. But this is very different from saying that the not-signed up branch has lower amplitude after T1 than it would have had after T1 if you had not signed up for cryonics at T1. In fact, the latter statement is necessarily false if physics really is timeless.

I think this latter point is what the other posters are driving at. It is true that if there is a branch at T1 where some yous go down a path where they sign up and others don't, then the amplitude for not-signed-up is lower after T1. But this happens even if this particular you doesn't go down the signed-up branch. What matters is that the branch point occurs, not which one any specific you takes.

In other words, amplitude is always being seeped from the not-signed-up branch, even if some particular you keeps not leaving that branch.

Comment author: Doug_S. 03 June 2008 02:46:46PM 1 point [-]

Random question for Eliezer:

If, today, you had the cryopreserved body of Genghis Khan, and had the capacity to revive it, would you? (Remember, this is the guy who, according t legend, said that the best thing in life was to crush your enemies, see them driven before you, and hear the lamentation of the women.)

(As Unknown suggests, I'd rather have a "better" person exist in the future than have "me" exist in the future. What I'd do in a post-Singularity future is sign up to be a wirehead. The future doesn't need more wireheads.)

Comment author: gwern 21 June 2009 01:07:28AM 4 points [-]

If, today, you had the cryopreserved body of Genghis Khan, and had the capacity to revive it, would you? (Remember, this is the guy who, according t legend, said that the best thing in life was to crush your enemies, see them driven before you, and hear the lamentation of the women.)

Absolutely. You could raise millions just from the historians of Europe & Asia who would kill to talk to Genghis Khan; and then there's all the genetic and medical research one could do on an authentic living/breathing person of a millennium ago. (More tests of Sapir-Whorf, anyone?)

Comment author: TGGP4 03 June 2008 02:47:26PM 0 points [-]

Kaj Sotala, it seems you have stumbled upon the apocalyptic imperative.

Comment author: iwdw 03 June 2008 02:53:06PM 0 points [-]

@Ian Maxwell: It's not about the yous in the universes where you have signed up -- it's about all of the yous that die when you're not signed up. i.e. none of the yous that die on your way to work tommorow are going to get frozen.

(This is making me wonder if anyone has developed a corresponding grammar for many worlds yet...)

Comment author: Brandon_Reinhart 03 June 2008 03:24:53PM 0 points [-]

I'm a member of Alcor. I wear my id necklace, but not the bracelet. I sometimes wonder how much my probability of being successfully suspended depends on wearing my id tags and whether I have a significantly higher probability from wearing both. I've assigned a very high (70%+) probability to wearing at least one form of Alcor id, but it seems an additional one doesn't add as much, assuming emergency response personnel are trained to check the neck & wrists for special case ids. In most cases where I could catastrophically lose one form of id (such as dismemberment!) I would probably not be viable for suspension. What do you other members think?

Comment author: David_Solomon 03 June 2008 03:36:13PM -1 points [-]

I can understand why creating a reconstruction of a frozen brain might still be considered 'you'. But what happens if multiple versions of 'you' are created? Are they all still 'you'? If I create 4 reconstructions of a brain and put them in four different bodies, punching one in the arm will not create nerve impulses in the other three. And the punched brain will begin to think different thoughts ('who is this jerk punching me?').

In that case, all 4 brains started as 'you', but will not experience the same subsequent thoughts, and will be as disconnected from each other as identical twins.

This is basically the first Parfit example, which I note you don't actually address. Is the 'you' on mars the same as 'you' on Earth? And what exactly does that mean if the 'you' on earth doesn't get to experience the other one's sensations first hand? Why should I care chat happens to him/me?

Comment author: Constant2 03 June 2008 04:32:32PM -1 points [-]

note that Parfit is describing thought experiments, not necessarily endorsing them.

I spy with my little eye something beginning with D.

Comment author: poke 03 June 2008 04:39:38PM 3 points [-]

I knew this was where we were headed when you started talking about zombies and I knew exactly what the error would be.

Even if I accept your premises of many-worlds and timeless physics, the identity argument still has exactly the same form as it did before. Most people are aware that atomic-level identity is problematic even if they're not aware of the implications of quantum physics. They know this because they consume and excrete material. Nobody who's thought about this for more than a few seconds thinks their identity lies in the identity of the atoms that make up their bodies.

Your view of the world actually makes it easier to hold a position of physical identity. If you can say "this chunk of Platonia is overlapping computations that make up me" I can equally say "this chunk of Platonia is overlapping biochemical processes that make up me." Or I can talk about the cellular level or whatever. Your physics has given us freedom to choose an arbitrary level of description. So your argument reduces to to the usual subjectivist argument for psychological identity (i.e., "no noticeable difference") without the physics doing any work.

Comment author: Robin_Brandt 03 June 2008 04:42:05PM 0 points [-]

from http://www.edge.org/q2008/q08_5.html#smolin

"Other physicists argue that aspects of time are real, such as the relationships of causality, that record which events were the necessary causes of others. Penrose, Sorkin and Markopoulou have proposed models of quantum spacetime in which everything real reduces to these relationships of causality."

I guess Eliezer is already aware of these theories...

Comment author: michael_vassar3 03 June 2008 05:13:00PM 5 points [-]

Kaj: No, more aren't born every minute, they are all simply there, and if one cannot tolerate vanishingly small frequencies or probabilities then there will always be things other than your brain spontaneously configuring themselves into "your brain resolved to abandon those you had resolved to help" for every real or hypothetical "someone" you might resolve to help. For what its worth though, if "you" is the classical computation approximated by your neurons then it isn't "you" in the personal continuity relevant sense that does any given highly improbable thing. The causal relations that cause unlikely behaviors exist only in the configuration space of the universe. They differ from the causal relations that exist in the abstract deterministic computation that you probably experience being.

Frank: See Kaj

Eliezer: What's up with continuous physics from an infinite set atheist?

Unknown: 2 seems plausible but it's definitely not an argument that most people would accept

Will Pearson: Shut up and multiply. 150K/day adds up to about 3B after 60 years, which is a conservatively high estimate for how long we need. Heads have a volume of a few liters, call it 3.33 for convenience, so that's 10M cubic meters. Cooling involves massive economies of scale, as only surfaces matter. All we are talking about is, assuming a hemispherical facility, 168 meters of radius and 267,200 square meters of surface area. Not a lot to insulate. One small power plant could easily power the maintenance of such a facility at liquid nitrogen temperatures.

Comment author: Wiseman 03 June 2008 05:14:54PM 0 points [-]

Err, how can two copies of a person be *exactly* the same when the gravitational forces on each will both be different? Isn't the very idea that you can transfer actual atoms in the universe to a new location while somehow ensuring that this transfer doesn't deterministically guarantee being able to determining which person "caused" the *copy* to exist (I.E. the original), physical nonsense?

While molecules may not have invisible "unique ID" numbers attached to them, they are unique in the sense of quantum evolution, preserving the "importance" of one atom distinguished from another.

Comment author: RobinHanson 03 June 2008 05:22:06PM 4 points [-]

Is there really anyone who would sign up for cryonics except that they are worried that their future revived self wouldn't be made of the same atoms and thus would not be them? The case for cryonics (a case that persuades me) should be simpler than this.

Comment author: bliumchik 06 June 2012 04:27:40AM *  0 points [-]

I agree. I'd be more worried about civilisation collapsing in the interim between being frozen and the point when people would have worked out how to revive me.

Comment author: Kenny 25 March 2013 11:43:49PM 0 points [-]

Why would you worry about that? Wouldn't you worry instead about the opportunity costs of signing-up for cryonics?

Comment author: Eliezer_Yudkowsky 03 June 2008 05:33:26PM 2 points [-]

@Kaj:

I find little comfort in the prospect of the "betrayal branches" being vanishingly few in frequency - in absolute numbers, their amount is still unimaginably large, and more are born every moment.

Kaj, you have to learn to take comfort in this. Not taking comfort in it is not a viable option.

I'm serious. Otherwise you'll buy lottery tickets because some version of you wins, make inconsistent choices on the Allais paradox, choose SPECKS over TORTURE...

Shut up and multiply. In a Big World there is no other choice.

Comment author: Unknown 03 June 2008 05:55:59PM 1 point [-]

Kaj didn't suggest that there is any other viable option. He suggested killing off the human race.

This strategy would fail too, however, since it would not succeed on every branch.

Comment author: Sebastian_Hagen2 03 June 2008 05:57:40PM 0 points [-]

Is the 'you' on mars the same as 'you' on Earth?

There's one of you on earth, and one on mars. They start out (by assumption) the same, but will presumably increasingly diverge due to different input from the environment. What else is there to know? What does the word 'same' mean for you?

And what exactly does that mean if the 'you' on earth doesn't get to experience the other one's sensations first hand? Why should I care chat happens to him/me?

That's between your world model and your values. If this happened to me, I'd care because the other instance of myself happens to have similar values to the instance making the judgement, and will therefore try to steer the future into states which we will both prefer.

Comment author: Roland2 03 June 2008 05:58:01PM 0 points [-]

Eliezer,

ok, thanks for the link.

Comment author: DaveInNYC 03 June 2008 05:59:53PM 1 point [-]

I have been seriously considering cryonics; if the MWI is correct, I figure that even if there is a vanishingly small chance of it working, "I" will still wake up in one of the worlds where it does work. Then again, even if I do not sign up, there are plenty of worlds out there where I do. So signing up is less of an attempt to live forever as it is an attempt to line up my current existence with the memory of the person who is revived, if that makes any sense. To put it another way, if there is a world where I procrastinate signing up until right before I die, the person who is revived will have 99.9% of the same memories as someone who did not sign up at all, so if I don't end up signing up I do not lose much.

FWIW, I sent an email to Alcor a while ago that was never responded to, which makes me wonder if they have their act together enough to preserve me for the long haul.

On a related note, is there much agreement on what is "possible" as far as MWI goes? For example, in a classical universe if I know the position/momentum of every particle, I can predict the outcome of a coin flip with 1.0 probability. If we throw quantum events in the mix, how much does this change? I figure the answer should be in the range of (1.0 - tiny number) and (0.5 + tiny number).

Comment author: HalFinney 03 June 2008 06:16:46PM 1 point [-]

I wrote a comment this morning on the monthly open thread which addresses some of the questions that have been raised above, but I will copy it here since that is a stale thread.

A couple of people asked about the relationship between quantum randomness and the macroscopic world.

Eliezer wrote a long essay here, http://www.sl4.org/wiki/KnowabilityOfFAI, about (among other things) the difference between unpredictability of intelligent decisions, and randomness. Decisions we or someone else make may be unpredictable beforehand, but that doesn't mean they are random. It may well be that even for a close and difficult decision where it felt like we could have gone either way, that in the vast majority of the MWI branches, we would have decided the same way.

At the same time, it is clear that there would be at least some branches where we would have decided differently. The brain ultimately depends on chemical processes like diffusion that have a random component, and this randomness will be influenced by quantum effects as molecules interact. So there would be some quantum fluctuations that could cause neurons to behave differently, and ultimately lead to different brain activities. This means that at the philosophical level, we do face the fact that every decision we make goes "both ways" in different branches. Our decision making is then a matter of what fraction of the branches go which way, and our mental efforts can be thought of as maximizing the fraction of good outcomes.

It would be interesting to try to figure out the degree to which quantum effects influence other macroscopic sources of randomness. Clearly, due to the butterfly effect, storms will be highly influenced by quantum randomness. If we reset the world to 5 years ago and put every molecule on the same track, New Orleans would not have been destroyed in almost all cases. How about a coin flip? If it comes up heads, what fraction of the branches would have seen tails? My guess is that the major variable will be the strength with which the coin is thrown by the thumb and arm. At the molecular level this will have two influences: the actin and myosin fibers in the muscles, activated by neurotransmitter packets; and the friction between the thumbnail and the forefinger which determines the exact point at which the coin is released. The muscle activity will have considerable quantum variation in individual fiber steps, but there would be a huge number of fibers involved, so I'd guess that will average out and be pretty stable. The friction on the other hand would probably be nonlinear and chaotic, an avalanche effect where a small change in stickiness leads to a big change in overall motion. I can't come up with a firm answer on this basis, but my guess would be that there is a substantial but not overwhelming quantum effect, so that we would see close to a 50-50 split among the branches. I wonder if anyone has attempted a more quantitative analysis.

One thing I will add, I imagine that ping-pong ball based lottery machines would be substantially affected by quantum randomness. The many bounces will lead to chaotic behavior, sensitive dependence on initial conditions, and even very small randomness due to quantum effects during collisions will almost certainly IMO be amplified to produce macroscopically different circumstances after several seconds.

Comment author: iwdw 03 June 2008 06:36:20PM 0 points [-]

Is there really anyone who would sign up for cryonics except that they are worried that their future revived self wouldn't be made of the same atoms and thus would not be them? The case for cryonics (a case that persuades me) should be simpler than this.

I think that's just a point in the larger argument that whatever the "consciousness we experience" is, it's at sufficiently high level that it does survive massive changes at at quantum level over the course of a single night's sleep. If worry about something as seemingly disastrous as having all the molecules in your body replaced with identical twins can be shown to be unfounded, then worrying about the effects of being frozen for a few decades on your consciousness should seem to be similarly unfounded.

Comment author: Patrick_(orthonormal) 03 June 2008 06:59:46PM 1 point [-]

Dave,

Well, if you resolve not to sign up for cryonics and if the thinking on Quantum Immortality is correct, you might expect a series of weird (and probably painful) events to prevent you indefinitely from dying; while if you're signed up for it, the vast majority of the worlds containing a later "you" will be the ones revived after a peaceful death. So there's a big difference in the sort of experience you might anticipate, depending on whether you've signed up.

Comment author: Nick_Tarleton 03 June 2008 07:25:48PM 0 points [-]

Also, if you count on quantum immortality alone, the measure of future-yous surviving through freakish good luck will be much smaller than the measure that would survive with cryonics. I'm not sure how this matters, though, because naive weighting seems to imply a very steep discount rate to account for constant splitting, which seems absurd.

Comment author: Kaj_Sotala 03 June 2008 07:46:54PM 0 points [-]

I suppose I'll just have to deal with it, then. Sigh - I was expecting there to be some more cheerful answer, which I'd just failed to realize. Vassar's response does help a bit.

Comment author: Wiseman 03 June 2008 08:13:24PM -1 points [-]

Kaj - there is a more cheerful answer. And this is it: Many-Worlds isn't true. Although Eliezer may be confident, the final word on the issue is still a long way off. Eliezer has been illogical on enough of his reasoning that there is reason to question that confidence.

Comment author: Nick_Tarleton 03 June 2008 08:20:53PM 2 points [-]

Only if Many-Worlds isn't true and the universe is finite or repeats with a finite period and Tegmark's ultimate ensemble theory is false. Personally, I find that prospect more disturbing for some reason.

Comment author: Kaj_Sotala 03 June 2008 08:31:26PM 1 point [-]

Wiseman: Yes, that's a possibility. But even if I only gave MWI a, say, 30% probability of being true, the thought of it being even that likely would continue to bother me. In order to avoid feeling the anguish through that route, I'd need to make myself believe the chance for MWI being true was far lower than what's rational. In addition to that being against my principles, I'm not sure if it was ethical, either - if MWI really is true, or even if there's a chance of it being true, then that should influence my behavior somehow, by e.g. avoiding having offspring so there'd at least be less sentients around to experience the horror of MWI (not that I'd probably be having kids pre-Singularity anyway, but that was the first example that came to mind - avoiding situations where I'm in a position to harm somebody else would probably also be good).

Thanks for trying to help, though.

Comment author: Wiseman 03 June 2008 08:58:19PM 0 points [-]

In that case I don't think MWI says anything we didn't already know: specifically that 'stuff happens' outside of our control, which is something which we have to deal with even in non-quantum lines of thought. Trying to make choices different when acknowledging that MWI is true probably will result in no utility gain at all, since saying that x number of future worlds out of the total will result in some undesirable state, is the same as saying, under copenhagen, the chances it will happen to you is x out-of total. And that lack of meaningfull difference should be a clue as to MWI's falshood.

In the end the only way to guide our actions is to abide by rational ethics, and seek to improve those.

Comment author: Recovering_irrationalist 03 June 2008 09:35:03PM 1 point [-]

I think the entire post makes sense, but what if...

Adam signs up for cryonics.

Brian flips a coin ten times, and in quantum branches where he get all tails he signs up for cryonics. Each surviving Brian makes a few thousand copies of himself.

Carol takes $1000 and plays 50/50 bets on the stock market till she crashes or makes a billion. Winning Carols donate and invest wisely to make positive singularity more likely and negative singularity less likely, and sign up for cryonics. Surviving Carols run off around a million copies each, but adjusted upwards or downwards based how nice a place to live they ended up in.

Assuming Brian and Carol aren't in love (most of her won't get to meet any of him at the Singularity Reunion), who's better off here?

Comment author: Recovering_irrationalist 03 June 2008 09:39:13PM 0 points [-]

(Assume Adam's a Xeroxphobe)

Comment author: Brandon_Reinhart 03 June 2008 10:07:02PM 0 points [-]

RI - Aren't Surviving Brian Copies [1-1000] are each their own entity? Brian-like entities? "Who is better off" are any Brian-like entities that managed to survive, any Adam-like entities that managed to survive, and any Carol-like entities that managed to survive. All in various infinite forms of "better off" based on lots of other splits from entirely unrelated circumstances. Saying or implying that Carol-Current-Instant-Prime is better off because more future versions of her survived than Adam-Current-Instant-Prime seems mistaken, because future versions of Adam or Carol are all their own entities. Aren't Adam-Next-Instant-N and Adam-Current-Instant-Prime also different entities?

And isn't multiplying infinities by finite integers to prove values through quantitative comparison an exercise doomed to failure?

All this trying to compare the qualitative values of the fates of infinities of uncountable infinite-infinities seems somewhat pointless. Also: it seems to be an exercise in ignoring probability and causality to make strange points that would be better made in clear statements.

>:(

I might just misunderstand you.

Comment author: David_Solomon 03 June 2008 10:13:18PM 0 points [-]

Sebastian:

I see your point that given the atoms are what they are, they are 'the same person', but can't get around the sense that it still matters on some level.

What if cryonics were phrased as the ability to create an identical twin from your brain at some point in the future, rather than 'you' waking up. If all versions of people are the same, this distinction should be immaterial. But do you think it would have the same appeal to people?

Suppose you do a cryogenics brain scan and create a second version of yourself while you're still alive. Each twin might feel strong regard for the other, but there's no way they would actually be completely indifferent between pain for themselves and pain for their twin. They share a past up to a certain point, and were identical when created, but that's it. If another 'me' were created on mars and then got a bullet in the head, this would be sad, but no more so than any other death. It wouldn't feel like a life-extending boon when he was created, nor a horrible blow to my immortality when he was destroyed. How is cryogenics different from this?

Comment author: JulianMorrison 03 June 2008 10:32:19PM -1 points [-]

Quantum non-sameness of the configurations from moment to moment, and quantum absolute equality of "the same sorts of particles in the same arrangement" are both illustrative as extremes, but the question looks much simpler to me. Since I have every reason to suppose "the me of me" is informational, I can simply apply what I know of information: that it exists as patterns independent of a particular substrate, and that it can be copied and still be the original. If I'm copied then the two mes will start diverging and become distinguishable, but neither has a stronger claim.

Comment author: Patrick_(orthonormal) 03 June 2008 10:36:23PM -1 points [-]

David,

You're right not to feel a 'blow to your immortality' should that happen; but consider an alternate story:

You step into the teleport chamber on Earth and, after a weird glow surrounds you, you step out on Mars feeling just fine and dandy. Then somebody tells you that there was a copy of you left in the Earth booth, and that the copy was just assassinated by anti-cloning extremists.

The point of the identity post is that there's really no difference at all between this story and the one you just told, except that in this story you subjectively feel you've traveled a long way instead of staying in the booth on Earth.

Both of the copies are you (or, more precisely, before you step into the booth each copy is a future you); and to each copy, the other copy is just a clone that shares their memories up to time X.

Comment author: David_Solomon 03 June 2008 10:41:21PM 0 points [-]

Sebastian:

Take this as a further question. One of the key distinctions between the 'you you' and the 'identical twin you' is the types of sacrifice I'll make for each one. Notwithstanding that I can't tell you why I'm still the same person when I wake up tomorrow, I'll sacrifice for my future self in ways that I won't for an atom-exact identical twin.

If you truly believe that 'the same atoms means its 'you' in every sense', suppose I'm going to scan you and create an identical copy of you on mars. Would you immediately transfer half your life savings to a bank account only accessible from mars? What if I did this a hundred times? If the same atoms make it the same person, why wouldn't you?

And if you don't really have the same regard for a 'copy' of yourself while you're still alive, why should this change when the original brain stays cryogenically frozen and a copy is created?

Comment author: Caledonian2 03 June 2008 10:54:45PM 0 points [-]

If you truly believe that 'the same atoms means its 'you' in every sense', suppose I'm going to scan you and create an identical copy of you on mars. Would you immediately transfer half your life savings to a bank account only accessible from mars?

Even assuming that I could confirm where my money was actually going, I don't think a copy of myself left on Mars would have much use for money. So, no.

Comment author: 03 June 2008 11:08:00PM 0 points [-]

If you truly believe that 'the same atoms means its 'you' in every sense', suppose I'm going to scan you and create an identical copy of you on mars. Would you immediately transfer half your life savings to a bank account only accessible from mars?

Absolutely, as there is a 50% that after the copy "I" will be the one ending up on Mars. If 100 copies were going to be made, I would be pretty screwed; I think I would move to a welfare state first :)

Alternatively, I would ask that they pick one of the copies at random and give him the money and kill the other 99. Of course, this would have the same effect as the copies never being made (in a sense).

Comment author: Recovering_irrationalist 03 June 2008 11:19:00PM 0 points [-]

Brandon:And isn't multiplying infinities by finite integers to prove values through quantitative comparison an exercise doomed to failure?

Infinities? OK, I'm fine with my mind smeared frozen in causal flowmation over countlessly splitting wave patterns but please, no infinite splitting. It's just unnerving.

Comment author: John_Faben 04 June 2008 12:33:00AM 2 points [-]

I get the feeling a lot of proponents of cryonics are a bit like those who criticize prediction markets, but refuse to bet on them. If you really believe that signing up for cryonics is so important, why aren't you being frozen now? Surely there are large numbers of branches in which your brain gets irretrievably destroyed tomorrow - if the reward for being frozen is so big, why wait?

Comment author: Phil_Goetz 04 June 2008 01:25:00AM 0 points [-]

The thought of I - and yes, since there are no originals or copies, the very I writing this - having a guaranteed certainty of ending up doing that causes me so much anguish that I can't help but thinking that if true, humanity should be destroyed in order to minimize the amount of branches where people end up in such situations. I find little comfort in the prospect of the "betrayal branches" being vanishingly few in frequency - in absolute numbers, their amount is still unimaginably large, and more are born every moment.

To paraphrase:

Statistically, it is inevitable that someone, somewhere, will suffer. Therefore, we should destroy the world.

Eli's posts, when discussing rationality and communication, tend to focus on failures to communicate information. I find that disagreements that I have with "normal people" are sometimes because they have some underlying bizarre value function, such as Kaj's valuation (a common one in Western culture since about 1970) that Utility(good things happening in 99.9999% of worlds - bad things happening in 0.0001% of worlds) < 0. I don't know how to resolve such differences rationally.

Comment author: Court 04 June 2008 01:27:00AM -2 points [-]

As a matter of historical coherence, as it were, see Nagarjuna's Mūlamadhyamaka-kārikā (Fundamental Verses of the Middle Way). Concerning the point that 'nothing happens,' you have more or less arrived at the same conclusions, though needless to say his version lacks the fancy mathematical footwork. I tend to think that your fundamental position regarding the physical nature of existence, insofar as I understand it, is probably correct. It's where you go from there that's a little more troubling.

Nagarjuna extrapolates from his views that via the Law of Karma we can reach Nirvana; Eliezer extrapolates from his views that via the Laws of Physics we can reach the Singularity. Both hold that their Law(s) do not require our assent; they continue to operate whether we believe in them them or not, and furthermore, their operation is inevitable. I am very skeptical that this follows in either case.

As regards cryonics, it seems to me what Eliezer is doing is fairly simple: he's taking Pascal's Wager. Pascal wagered on gaining immortality via God, Eliezer wagers on gaining immortality via the Singularity. There's no harm in it, per se, any more than there was in Pascal's being a believing Christian. But one of the major fallacies in Pascal's Wager is the assumption that we know God's characteristics, e.g., if I am believe in Him, He will reward me with eternal life. The same fallacy seems to apply to Eliezer's Wager - even if the Singularity is true, how can we know its characteristics, e.g., that some future benevolent AI will re-animate his frozen brain?

Perhaps, Eliezer, you could in future posts fill in the gaps .

Comment author: Peter6 04 June 2008 02:30:00AM 0 points [-]

"Will Pearson: Shut up and multiply. 150K/day adds up to about 3B after 60 years, which is a conservatively high estimate for how long we need. Heads have a volume of a few liters, call it 3.33 for convenience, so that's 10M cubic meters. Cooling involves massive economies of scale, as only surfaces matter. All we are talking about is, assuming a hemispherical facility, 168 meters of radius and 267,200 square meters of surface area. Not a lot to insulate. One small power plant could easily power the maintenance of such a facility at liquid nitrogen temperatures.

Michael Vassar - you've also assumed here that the number "150K/day" is going to remain constant over the next 60 years: it's going to increase.

I'm serious. Otherwise you'll buy lottery tickets because some version of you wins, make inconsistent choices on the Allais paradox, choose SPECKS over TORTURE...

Eliezer - I'm largely unconvinced by MWI, or at your interpretation. But I'm not going try to argue it here.

You're a great writer, you're clever, and very quick. But you haven't got a clue about morality. Your torture-over-specks conclusion, and the line of argument which was used to reach it, is *cripplingly* flawed. And every time you repeat it, you delude minds.

Comment author: Nick_Tarleton 04 June 2008 02:55:00AM 0 points [-]

Phil: What makes you say negative utilitarianism is "a common view in Western culture since 1970"?

Pascal wagered on gaining immortality via God, Eliezer wagers on gaining immortality via the Singularity.... The same fallacy seems to apply to Eliezer's Wager - even if the Singularity is true, how can we know its characteristics, e.g., that some future benevolent AI will re-animate his frozen brain?

See Artificial Intelligence as a Positive and Negative Factor in Global Risk.

Comment author: Allan_Crossman 04 June 2008 03:06:00AM 0 points [-]

John Faben: "If you really believe that signing up for cryonics is so important, why aren't you being frozen now?"

I'm not sure anyone's claimed that cryonics is 100% guaranteed to work. So committing suicide just to get frozen would be an odd thing to do, given such uncertainty.

Comment author: Eliezer_Yudkowsky 04 June 2008 03:56:00AM 5 points [-]

Cryonicists have a saying: "Being cryonically suspended is the second worst thing that can happen to you."

Comment author: Ben_Wraith 04 June 2008 04:03:00AM 0 points [-]

Michael Anissimov raises a good question about post length. Eliezer, I think some of your posts could benefit from being shorter. You have to say what you need to, but people are more likely to read shorter blog posts.

Even before I'd read the series on quantum physics, I can't imagine fear of still being the same person as a reason I wouldn't sign up for cryonics. My understanding was that all the atoms making up your body change many times in a lifetime anyway, and while that used to distress me I wouldn't have seen it as a problem that would be exacerbated greatly by signing up for cryonics. The only reason I haven't signed up for cryonics yet is money, but hopefully I'll be able to overcome that soon.

Comment author: Erik_Mesoy 04 June 2008 05:54:00AM 0 points [-]

Something's been bugging me about MWI and scenarios like this: am I performing some sort of act of quantum altruism by not getting frozen since that means that "I" will be experiencing not getting frozen while some other me, or rather set of world-branches of me, will experience getting frozen?

Comment author: Sebastian_Hagen2 04 June 2008 07:28:00AM 0 points [-]

What if cryonics were phrased as the ability to create an identical twin from your brain at some point in the future, rather than 'you' waking up. If all versions of people are the same, this distinction should be immaterial. But do you think it would have the same appeal to people?

I don't know, and unless you're trying to market it, I don't think it matters. People make silly judgements on many subjects, blindly copying the majority in this society isn't particularly good advice.

Each twin might feel strong regard for the other, but there's no way they would actually be completely indifferent between pain for themselves and pain for their twin.

Any reaction of this kind is either irrational, based on divergence which has already taken place, or based on value systems very different from my own. In real life, you'd probably get a mix of the first two, and possibly also the last, from most people.

If another 'me' were created on mars and then got a bullet in the head, this would be sad, but no more so than any other death. It wouldn't feel like a life-extending boon when he was created, nor a horrible blow to my immortality when he was destroyed.

For me, this would be a quantitative judgement: it depends on how much both instances have changed since the split. If the time lived before the split is significantly longer than that after, I would consider the other instance a near-backup, and judge the relevance of its destruction accordingly. Aside from the aspect of valuing the other person as a human like any other that also happens to share most of your values, it's effectively like losing the only (and somewhat out-of-date) backup of a very important file: No terrible loss if you can keep the original intact until you can make a new backup, but an increased danger in the meantime.

If you truly believe that 'the same atoms means its 'you' in every sense', suppose I'm going to scan you and create an identical copy of you on mars. Would you immediately transfer half your life savings to a bank account only accessible from mars? What if I did this a hundred times?

Maybe, maybe not, depends on the exact strategy I'd mapped out beforehand for what each of the copies will do after the split. If I didn't have enough foresight to do that beforehand, all of my instances would have to agree on the strategy (including allocation of initial resources) over IRC or wiki or something, which could get messy with a hundred of them - so please, if you ever do this, give me a week of advance warning. Splitting it up evenly might be ok in the case of two copies (assuming they both have comparable expected financial load and income in the near term), but would fail horribly for a hundred; there just wouldn't be enough money left for any of them to matter at all (I'm a poor university student, currently; I don't really have "life savings" in transferrable format).

Comment author: Will_Pearson 04 June 2008 07:31:00AM 0 points [-]

Michael Vasser, thanks for the start of the calculation. Shame you didn't actually finish it by giving energy needed to maintain temp per metre squared. This could be from 1 watt to 1000 watts, I don't personally have a good estimate of insulation/nitrogen loss at this temp.

Taking into account how much energy will be needed to take 150k heads down to -200 degrees C, would also be good. I am pressed for time, so I may not get around to it.

Comment author: Court 04 June 2008 08:58:00AM 0 points [-]

Nick,

Nothing about cryonics there. That was what I was referring to specifically in bringing up Pascal's Wager. Or am I missing something?

Comment author: Tim_Tyler 04 June 2008 10:11:00AM 2 points [-]

Re: "In reality, physics is continuous."

That has yet to be established.

The universe could turn out to be finite and discrete - e.g. see my site:

http://finitenature.com/

It is confusion to argue from the continuity of the wave equation to the
continuity of the underlying physics - since there is no compelling reason to think that the wave equation is the final word on the issue - and discrete phenomena often look continuous if you observe them from a sufficiently great distance - e.g. see lattice gasses.

http://en.wikipedia.org/wiki/Loop_quantum_gravity is an example of a more modern discrete theory.

Comment author: Günther_Greindl 04 June 2008 10:33:00AM 0 points [-]

@Kaj: There are more cheerful prospects. I think you are still too much caught up in an "essence" of you which acts. There is no such thing. There is no dichotomy between you and the universe.

The anguish you feel is anguish about your own (the universes!) suffering. Try to be happy, you will increase happiness overall.

Eastern philosophy helps, it merges well with materialism. You are only disturbed if you can't get rid of deeply-conditioned Western philosophical assumptions.

Reading recommendations:

Anything by Alan Watts (start with "The Way of Zen").
Raymond Smullyan's "The Tao is Silent"
Joseph Goldstein's "One Dharma: The Emerging Western Buddhism" is excellent also.

On my reading list (looks highly relevant) is this book:
Kolak, Daniel. "I Am You: The Metaphysical Foundations for Global Ethics"

Maybe you want to check that out too.

Some inspiriation from Lao Tse's Dao de jing (verse two):

Under heaven all can see beauty as beauty only because there is ugliness.
All can know good as good only because there is evil.

Therefore having and not having arise together.
Difficult and easy complement each other.
Long and short contrast each other:
High and low rest upon each other;
Voice and sound harmonize each other;
Front and back follow one another.

Therefore the sage goes about doing nothing, teaching no-talking.
The ten thousand things rise and fall without cease,
Creating, yet not.
Working, yet not taking credit.
Work is done, then forgotten.
Therefore it lasts forever.


Cheers,
GĂƒÂźnther


Comment author: steven 04 June 2008 01:10:00PM 0 points [-]

I think Kaj's concerns are silly and I'm all for shutting up and multiplying, but is there a strong argument why the expected utility of better-than-death outcomes outweighs the expected negative utility of worse-than-death outcomes (boots stamping on human faces forever and the like)?

Comment author: Will_Pearson 04 June 2008 10:13:00PM 0 points [-]

Hmm, assuming dewar levels of insulation* and a few other numbers guestimated like joules required to create a litre of N2 (2 KWh/l) I got 7 litres lost per second and a 50KW supply for energy.

* I'm not sure this is a safe assumption. A dewar is fully sealed, we are putting 495000 litres of material in per day.

It looks like the cost to freeze the heads would dwarf this as well, 137 litres per second of more dense material with higher specific heat capacity to cool to liquid nitrogen levels. Probably up to the megawatt range, if not more. Not taking into account travel energy costs and freezing costs while travelling.

It would be interesting to see whether it is better to have 1 giant store or many smaller ones. Anyone up for brainstorming a design? I am not too interested in personal survival but if it can be done for minimal-ish cost it would be very worthwhile from an archival of humanity point of view.

Comment author: Nick_Tarleton 04 June 2008 10:32:00PM 0 points [-]

Court, that paper addresses the general question of what we can know about the outcome of the Singularity.

Something's been bugging me about MWI and scenarios like this: am I performing some sort of act of quantum altruism by not getting frozen since that means that "I" will be experiencing not getting frozen while some other me, or rather set of world-branches of me, will experience getting frozen?

Not really, since your decision determines the relative sizes of the sets of branches.

Comment author: Psy-Kosh 04 June 2008 10:34:00PM 0 points [-]

Eliezer: "my own insurance policy, with CI."? I thought you had said you were signed up as a neuro rather than full body. As far as I know, CI only does full body rather than neuro.

(Isn't neuro supposed to be better, anyways? That is, better chance of "clean" brain vitrification?)

Comment author: Aaron7 05 June 2008 12:05:00AM -1 points [-]

Clearly, due to the butterfly effect, storms will be highly influenced by quantum randomness. If we reset the world to 5 years ago and put every molecule on the same track, New Orleans would not have been destroyed in almost all cases.

No, no, no. The vast majority will have New Orleans destroyed, but in slightly different ways. Yes, weather is chaotic, but it evolves in fairly set ways. The original Lorenz attractor is chaotic, but it has a definite shape that recurs.

Comment author: Luke_A_Somers 29 May 2012 03:33:20PM 0 points [-]

... therefore, you can predict that some hurricanes will occur in the area, but not precisely where they will be. The original statement is correct.

Comment author: Hopefully_Anonymous3 12 June 2008 08:09:00AM 1 point [-]

I don't think you've proven what you claim to have proven in this post, but it might work as propaganda to increase cyronics enrollment, which should be good for both of us.
Specifically, I don't think it's clear that (1) current cryonics technology prevents information-theoretic death, (2) that if I'm "revived" from cryonics such that it fools discernment technology of that era, I'm actually having a subjective conscious experience of being alive and conscious. And perhaps discernment technology 30 years later will tragically demonstrate why, and what could've been done differently to preserve me as a subjective conscious entity, (3) future societies with the technology to revive us will choose to.

Separate from propaganda, I think 1-3 are important areas to focus on in terms of research and innovation. We don't want to be fooled by our own propaganda and thus fail to rationally maximize our persistence odds. We don't want to be prisoners of our own myths.

Comment author: Eymer 24 June 2008 06:33:00PM 0 points [-]

Question for Eliezer and everyone else :

Would you really not care about dying if you knew you had a full backup body (with an up-to-date version of your brain) just waiting to be woken up ?

Comment author: ata 06 January 2011 02:02:14AM 0 points [-]

"up-to-date" as of the moment before I died? Yes, I would not mind.

Comment author: Jonii 08 October 2009 07:46:33PM 2 points [-]

Why do timeless physics require absence of repeating? How would things change even if universe repeated itself?

Comment author: ata 08 January 2011 01:44:59AM 0 points [-]

Bumping an old comment because I was wondering this too.

Comment author: Viliam_Bur 16 September 2011 12:10:04AM 0 points [-]

How would things change even if universe repeated itself?

Even then there would be no difference between repeating and non-repeating universe.

As an example, try to imagine 100 universes, each one exactly the same as our, in every last detail. Is it somehow different from having only 1 universe? No. Even infinitely many universes, as long as they are exactly the same, don't make any difference.

Now try to imagine one universe that somehow (despite the second law of thermodynamics) repeats. It follows the same laws, so it repeats exactly the same way, in every last detail. Is it somehow different from only repeating once? No.

Comment author: Baughn 24 October 2012 09:50:53AM 0 points [-]

I'm inclined to think "yes", actually. I think redundancy matters..

Before expounding on that, though, could you point me at any material that says it doesn't?

Comment author: Viliam_Bur 24 October 2012 02:10:31PM 2 points [-]

I have no material that directly says that.

Indirectly, though, what experience do you expect if there are 100 universes exactly the same as our in every detail, as opposed to if there is only 1 such universe?

Comment author: Baughn 24 October 2012 06:51:32PM *  1 point [-]

The same, if that was the entirety of existence.

Since we're postulating multiple universes, that's probably pretty unlikely though. I would expect to have an increased probability of existing in a universe with more copies, proportionally to the number of copies.

Comment author: Viliam_Bur 25 October 2012 07:33:25AM *  0 points [-]

So, let's suppose there is a universe A which exists only once, and a universe B which exactly repeats forever. Those universes are different, but a situation of "me, now" can happen in both of them. (Both universes happen to contain the same configuration of particles in a limited space at some time.) Then, I should expect to be in the universe B, because that is infinitely more probable.

Unfortunately, I don't know whether I just wrote a nonsensical sequence of words, or whether there is some real meaning in them.

Comment author: Baughn 26 October 2012 11:34:17PM *  0 points [-]

No, it sounds pretty meaningful to me.

I'm modeling this as if we have an (unbounded) computer executing all possible programs, some of which involve intelligences.. usually embedded in a universe. The usual dovetailer model, that is.

In the case you described, there would be two programs involved. One computes my life once, and then halts. The second runs the same program as the first, but in an infinite loop. And yes, in this case I would expect to find myself in program B in most samples. (Although, as I wrote that, there's no way to tell the difference.. make the obvious correction to fix that.)

I described it as all possible programs, though, which would certainly include things such as boltzmann brains. The reason I don't see that as a problem is.. the computational density of (my?) mind, strictly speaking, is what matters; not just the total number of instantiations, which over an infinite runtime is a nonsensical thing to ask about. Certainly there would be an infinite number of boltzmann brains, but they're rare; much rarer than, say, a cyclic universe.

Well. That said, the apparent scarcity of life in this universe, as opposed to computation-hungry but boring things like stars, seems to be a decent counterargument. I'm not sure how it'd work out, really. :O

Comment author: jvdubois 28 October 2013 05:39:11PM 0 points [-]

I think this sentence does not make sense. If a universe has some configuration, then it IS the UNIVERSE. It does not make sense that there are 100 of them

I imagine it like a sequence of numbers. There is 0, then there is 1 etc. It does not make sense that if you have sequence:

1,2,8,5,1

That there are two different occurences of a thing "number one. No matter how "many times" the number was used, it is still fundamentaly the number.

I think Elizier himself used a very good example of how things work like. Imagine that everything you know about our universe can be coded into a sequence of numbers. Everything - all its history etc. Now what meaning it has from inside of this universe that some powerful alien race with a lot of computing power can take this sequence and load it into a memory of some supercomputer? What if they load it and delete it it twice or million times? What if they load it on two computers simultaneously? It does not matter from within the universe. It just is.

Comment author: David_Gerard 25 January 2011 10:25:43PM *  5 points [-]

Do you know what it takes to securely erase a computer's hard drive? Writing it over with all zeroes isn't enough. Writing it over with all zeroes, then all ones, then a random pattern, isn't enough. Someone with the right tools can still examine the final state of a section of magnetic memory, and distinguish the state,

Minor note: this claim is obsolete and should not be used to make the point you're trying to make.

Peter Gutmann's original list of steps to erase a hard drive is obsolete. Gutmann himself is particularly annoyed that it appears to have taken on the status of a voodoo ritual. As that Wikipedia article notes, "There is yet no published evidence as to intelligence agencies' ability to recover files whose sectors have been overwritten, although published Government security procedures clearly consider an overwritten disk to still be sensitive. Companies specializing in recovery of damaged media (e.g., media damaged by fire, water or otherwise) cannot recover completely overwritten files. No private data recovery company currently claims that it can reconstruct completely overwritten data." Overwriting with random data is enough in practice in 2011, and was in 2008 for that matter.

Comment author: wedrifid 26 January 2011 12:45:10AM *  2 points [-]

Scientists have played with electron microscopes and established that in principle someone with the right tools could examine the final state of a section of magnetic memory and distinguish an earlier state. It's just that nobody has said tools in practice and the engineering tasks to create tools that worked reliably for the task is an absolute nightmare.

One could argue that the quoted claim is technically correct.

Comment author: David_Gerard 26 January 2011 01:52:18AM *  0 points [-]

Citation needed, one talkiing about hard disks as of 2008 at the earliest, or an equivalent magnetic problem.

A supporting claim needing to be stretched as far as "well, it's not technically false!" still strikes me as not being a good example to try to persuade people with.

Comment author: wedrifid 26 January 2011 02:14:07AM *  2 points [-]

Citation needed, one talkiing about hard disks as of 2008 at the earliest, or an equivalent magnetic problem.

I am reluctant to comply with demands for citations on something that is not particularly controversial and, more importantly, does not contradict the references you yourself provided. Apart from reading your own references (Gutmann and wikipedia) you can look at the most substantial criticism of the idea that there are real world agencies who could recover your overwritten data, that by Daniel Feenberg.

Gutmann mentions that after a simple setup of the MFM device, that bits start flowing within minutes. This may be true, but the bits he refers to are not from from disk files, but pixels in the pictures of the disk surface. Charles Sobey has posted an informative paper "Recovering Unrecoverable Data" with some quantitative information on this point. He suggests that it would take more than a year to scan a single platter with recent MFM technology, and tens of terabytes of image data would have to be processed.

His general point is that while there has been some limited success with playing with powerful microscopes the current process is so ridiculously impractical and unreliable that there is no chance any existing intelligence agency would be able to pull it off.

A supporting claim needing to be stretched as far as "well, it's not technically false!" still strikes me as not being a good example to try to persuade people with.

Not a position I have argued against, nor would I be inclined to.

Comment author: David_Gerard 27 January 2011 11:00:57AM 2 points [-]

Fair enough!

Comment author: TimFreeman 19 April 2011 05:09:04PM 3 points [-]

So what's timeless identity?

I read this article with the title "Timeless Identity", and there was a bunch of statements of the form "identity isn't this" and "identity isn't that", and at the end I didn't see a positive statement about how timeless identity works. Does the article fail to solve the problem it set out to solve, or did I read too fast?

Personally, I think the notion of identity is muddled and should be discarded. There is a vague preference about which way the world should be moved, there's presently one blob of protoplasm (wearing a badge with "Tim Freeman" written on it, as I write) that does a sloppy job of making that happen, and if cryonics or people-copying or an AI apocalypse or uploading happen, there will be a different number of blobs of something taking action to make it happen. The vague preference is more likely to be enacted if things exist in the world that are trying to make it happen, hence self-preservation is rational. No identity needed. The Buddhists are right -- there a transient collection of skandhas, not an indwelling essence, so there is no identity, timeless or otherwise.

So I'm not concerned about the possibility of there being no such thing as timeless identity, but I am slightly concerned that either the article has something good I missed, or groupthink is happening to the extent that none of the upvoted comments on this article are screaming "The Emperor has no clothes!", and I don't know which.

Thanks for the pointer to Parfit's work. I've added it to my reading list. Upvoted the article because of the reference to Parfit and the idea that maybe the interminable debates on the various transhumanist mailing lists actually didn't make significant progress on the issue.

Nitpick 1: if the odds of actual implementations of cryonics working is less than 50%, then maybe most of those 150K deaths actually are unavoidable, on the average. One failure mode is cryonics not working because we will lose an AI apocalypse, for example.

Nitpick 2: If the forces that prevent food and clean water from getting to the dying children in Africa would also prevent delivery of cryonics, then we can't blame ignorant first-worlders for their deaths.

Nitpick 3: I think cryonics would still make just as much sense in a deterministic world, so IMO you don't have to understand quantum mechanics to properly evaluate it.

I call these nitpicks because the essence of the argument is that there are many, many avoidable deaths happening every day on the average, and I agree with that.

Comment author: shokwave 19 April 2011 06:29:48PM 2 points [-]

The Buddhists are right

I always cringe at statements like this. I'm quite familiar with the Buddhist notion of no self, but I don't think for a second that study of Buddhist philosophy would convince anyone that a cryonically frozen person will wake up as themselves - in fact, given the huge stretch of time between freeze and unfreeze, there is a strong (but wrong) argument from Buddhist philosophy that cryonics wouldn't work.

And so if it bears a superficial similarity but doesn't output the same answers ... it is about as right as a logic gate that looks like AND but performs ALWAYS RETURN FALSE.

Comment author: TimFreeman 19 April 2011 10:53:48PM *  2 points [-]

I'm quite familiar with the Buddhist notion of no self, but I don't think for a second that study of Buddhist philosophy would convince anyone that a cryonically frozen person will wake up as themselves

If there is no self, then cryonics obviously neither works nor doesn't work at making a person wake up as themselves, since they don't have a self to wake up as. From this point of view, cryonics works if someone wakes up, and the person who originally signed up for cryonics would have preferred for that person to wake up over not having that person wake up, given the opportunity costs incurred when doing cryonics.

Cryonics is similar in kind to sleep or the passage of time in that way.

Whether most Buddhists are able to figure that out is another question. I agree that I'm not describing the Buddhist consensus on cryonics, and I agree that Buddhist philosophy does not motivate doing cryonics. My only points are that they're consistent, and that Buddhist philosophy frees me from urgently trying to puzzle out what "Timeless Identity" is supposed to mean.

I'm slightly concerned that the OP apparently doesn't say how timeless identity is supposed to work, and nobody seems to have noticed that.

Comment author: shokwave 20 April 2011 06:45:20AM *  2 points [-]

I'm slightly concerned that the OP apparently doesn't say how timeless identity is supposed to work, and nobody seems to have noticed that.

The explanation of identity starts when he kicks off around the many-worlds heads diagram. Specifically the part that makes timeless identity work (as long as you accept most reductionist physical descriptions of identity - configurations of neurons and synapses and such) is this:

We also saw in Timeless Causality that the end of time is not necessarily the end of cause and effect; causality can be defined (and detected statistically!) without mentioning "time". This is important because it preserves arguments about personal identity that rely on causal continuity rather than "physical continuity".

Comment author: TimFreeman 20 April 2011 12:44:01PM 0 points [-]

Ah. The assumption that identity = consciousness was essential to recognizing that this was an attempt to answer the question of how timeless identity works. He only mentions identity = consciousness in passing once, and I missed it the first time around, so the problem was that I was reading too fast. Thanks.

If you need a notion of identity, I agree that identity = consciousness is a reasonable stand to take.

Comment author: handoflixue 25 May 2011 12:31:47AM 0 points [-]

"If cryonics were widely seen in the same terms as any other medical procedure, economies of scale would considerably diminish the cost"

To what degree are these economies of scale assumed? Is it really viable, both practically and financially, to cryogenically preserve 150,000 people a day?

Is there any particular reason to suspect that investing this sort of funding in to cryonics research is the best social policy? What about other efforts to "cure death" by keeping people from dying in the first place (for instance, those technologies that would be the necessary foundations for restoring people from cryonics in the first place)?

I see cryonics hyped a lot here, and in rationalist / transhuman communities at large, and it seems like an "applause light", a social signal of "I'm rationalist; see, I even have the Mandatory Transhumanist Cryogenics Policy!"

Comment author: Eliezer_Yudkowsky 25 May 2011 01:46:35AM 10 points [-]

Liquid nitrogen is cheap, and heat loss scales as the 2/3 power of volume. Cryonically preserving 150,000 people per day would, I fully expect, be vastly cheaper than anything else we could do to combat death.

Comment author: ciphergoth 25 May 2011 07:53:52AM 4 points [-]

Could you tell us what you see in the way that cryonics is "hyped" that you would be less likely to see if people praised it simply because it was a good idea?

Comment author: handoflixue 25 May 2011 07:18:44PM 1 point [-]

I would expect to see a rational discussion of the benefits and trade-offs involved, in such a way as to let me evaluate, based on my utility function, whether this is a good investment for me.

Instead, I primarily see almost a "reversed stupidity" discussion, combined with what seems like in-group signalling: "See all these arguments against cryonics? They are all irrational, as I have now demonstrated. QED cryonics is rational, and you should signal your conformity to the Rationality Tribe by signing up today!"

I can totally understand why it's presented this way, but it reads off as "hype" because I almost never encounter anything else. It all seems to just naively assume that "preserving my individual life at any cost is a perfectly rational decision." Maybe that really is all the thought that goes in to it; if your utility function places a suitably high value on self-preservation, then there's not really a lot of further discussion required.

But I get the sense that there are deeper thoughts that just never get discussed, because everyone is busy fighting against the nay-sayers. There's a deep absence of arguments for cryonics, especially ones that actually take in to consideration social policy, and what else could be accomplished for $200K.

(Eliezer hinted at it, with his comments about economies of scale, but it was a mere footnote, and quite possibly the first time I've seen anyone discuss the issue from that perspective even briefly)

Comment author: ciphergoth 26 May 2011 01:07:52PM -3 points [-]

Looks like you've just found another way of saying "you're all irrational!" without providing evidence.

Comment author: handoflixue 26 May 2011 04:49:00PM 1 point [-]

It's more that all the arguments I see are aimed at a different audience (cryonics skeptics). I do not take this as very strong evidence of irrationality. On the other hand, anyone who posts here, I take that as decent evidence of rationality, especially people like Eliezer. So I assume with a high probability that either the people espousing it have a different utility function than I, or are simply not talking about the other half of the argument. I'm assuming that there is a rational reason, but objecting because I don't feel anyone is trying to rationally explain it to me :)

Loosely, in my head, there's the idea of a "negative" argument, which is just rebutting your opponent, or a "positive" argument which actually looks at the advantages of your position. I see hype, in-group signalling, and "negative" arguments. I'm interested in seeing some "positive" ones.

As far as evidence, I did actually just put up a post discussing specifically the "economies of scale" argument. It is thus far the only "positive" argument I've heard for it, aside from the (IMO) very weak argument of "who doesn't want immortality?" (I find it weak specifically because it ignores both availability and price, and glosses over how reliability is affected by those two factors as well)

Hopefully that was clearer!

Comment author: bcoburn 25 May 2011 11:17:34PM 3 points [-]

Mandatory link on cryonics scaling that basically agrees with Eliezer:

http://lesswrong.com/lw/2f5/cryonics_wants_to_be_big/

Comment author: handoflixue 26 May 2011 01:20:37AM *  1 point [-]

Unless modern figures have drifted dramatically, free storage would give you a whopping 25% off coupon.

This is based on the 1990 rates I found for Alcor. And based on Alcor's commentary on those prices, this is an optimistic estimate.

Source: http://www.alcor.org/Library/html/CostOfCryonicsTables.txt

Cost of cryogenic suspension (neuro-suspension only): $18,908.76

Cost of fund to cover all maintenance costs: $6,600

Proportional cost of maintenance: 25.87%


I'd also echo ciphergoth's request for any sort of actual citation on the numbers in that post; the entire post strikes me as making some absurdly optimistic assumptions (or some utterly trivial ones, if the author was talking about neuro-suspension instead of whole-body...)

Comment author: orthonormal 14 June 2011 06:59:35PM *  2 points [-]

The Ben Best Cryonics FAQ link is dead, or at least frozen.

Comment author: Vladimir_Nesov 15 June 2011 12:44:24AM 0 points [-]

Added link to a snapshot on Internet Archive (last snapshot was 31 Dec 2009, so it's possibly not available for some time now, but maybe not).

Comment author: amitpamin 21 June 2012 05:01:15AM 1 point [-]

I realize this is an old post and no one will read this comment... but I just wanted to say thank you. I myself signed up for cyronics just a month ago, but did, for example, wonder - will I be the same person? I still wonder that, but with slightly more perspective.

Comment author: Wei_Dai 20 December 2012 09:56:37AM *  6 points [-]

A sentient brain constructed to atomic precision, and copied with atomic precision, could undergo a quantum evolution along with its "copy", such that, afterward, there would exist no fact of the matter as to which of the two brains was the "original".

On the other hand, an ordinary human brain could undergo 100 years worth of ordinary quantum evolution along with its "copy", and probably 99 out of 100 naive human observers would still agree which one is the "original" and which is the "copy". It seems there must be a fact of the matter in this case, or else how did they reach agreement? By magic?

Given that physical continuity is an obvious fact of daily life, in our EEA and now, why can't "caring about physical continuity" be a part of our preferences/morality? In other words, if the above specially constructed sentient brain were to host a human mind, it doesn't seem implausible that it would consider both post-evolution versions of itself to be less valuable "copies" (due to loss of clear physical continuity) and would choose to avoid undergoing such quantum evolution if it could. This "physical continuity" may not have a simple definition in terms of fundamental physics, but then nobody said our values had to be simple...

EDIT: I've expanded this criticism into a discussion post.

"Consider another range of possible cases: the Physical Spectrum. These cases involve all of the different possible degrees of physical continuity...

"In a case close to the near end, scientists would replace 1% of the cells in my brain and body with exact duplicates. In the case in the middle of the spectrum, they would replace 50%. In a case near the far end, they would replace 99%, leaving only 1% of my original brain and body. At the far end, the 'replacement' would involve the complete destruction of my brain and body, and the creation out of new organic matter of a Replica of me."

(Reasons and Persons, p. 234.)

Parfit uses this to argue against the intuition of physical continuity pumped by the first experiment: if your identity depends on physical continuity, where is the exact threshold at which you cease to be "you"?

Isn't this just a variant of the Sorites paradox? (I can use it to argue that identity can't have anything to do with synapse connections: suppose I destroy your synapses one at a time, where is the exact threshold at which you cease to be "you"?) I'm surprised at Parfit's high reputation if he made arguments like this one.

Comment author: Indon 17 April 2013 11:28:21PM 2 points [-]

Since you're a computer guy (and I imagine many people you talk to are also computer-savvy), I'm surprised you don't use file/process analogues for identity.

  • If I move a file's physical location on my hard drive, it's obviously still the same file, because it has handle and data continuity. This is analogous to existing in different locations, being expressed with different atoms.
  • If I change the content of the file, it's obviously still the same file, because it has handle and location continuity. This is analogous to changing over not-technically-time-but-causal-effect-chains-that-we-may-as-well-call-time-for-convenience.
  • If I delete the file (actually just removing its' file handle in most modern systems) and use a utility to recover it, it's obviously still the same file, because it has location and data continuity. This is analogous to cryonics.

Identity is thus describable with three components: handle, data, and location continuity, only two of which are required at any given point. As for having just one:

  • If you have only handle continuity, you have two distinct objects with the same name.
  • If you have only data continuity, then you have duplicate work.
  • If you have only location continuity, you've reformatted.

All three break file identity.

As for cryonics, I would sign up if I could be convinced that I would not become obsolete or even detrimental to a society that resurrects me. And looking at some of the problems in my country already being caused by merely having a normally aging population at current social development rate, I don't even think it's a given that I could contribute meaningfully to society during the twilight of my at-present-natural life.

Comment author: Zaq 10 October 2013 10:32:03PM 3 points [-]

Eliezer, why no mention of the no-cloning theorem?

Also, some thoughts this has triggered:

Distinguishability can be shown to exist for some types of objects in just the same way that it can be shown to not exist for electrons. Flip two coins. If the coins are indistinguishable, then the HT state is the same as the TH state, and you only have three possible states. But if the coins are distinguishable, then HT is not TH, and there are four possible states. You can experimentally verify that the probability obeys the latter situation, and not the former. And of course, you can experimentally verify that electron pairs obeys the former situation, and not the latter. This is probably just because the coins are qualitatively distinct, while the electrons are not.

But it seems that if you did make a quantum copy (no-cloning theorem be damned!) then after a bit of interaction with the different environments, the two would become distinguishable (on the basis of developing different qualitative identities) and start behaving more like the coins than the electrons. In fact, if you're actually using the lightspeed limit then the reconstructed you would be several years younger, and immediately distinguishable from what the scanned you has since evolved into. At the time of reconstruction, the two are already acting like coins and not electrons. Does this break the argument? I'm not really sure, because the reconstructed you at the time of reconstruction would still be indistinguishable from the you at the time of scanning, if you could somehow get them both around at the same time.

Bonus! The reconstructed you could be seen to have a very qualitatively different time-evolution. The scanned you evolves throughout its entire history via a Hamiltonian which itself changes continuously as scanned-you moves continuously through your environment. Reconstructed you, however, has a clear discontinuity in its Hamiltonian at the time of reconstruction (the state is effectively instantly moved from one environment into a completely different environment). The state of the reconstructed you would still evolve continuously, it would just have a discontinuous derivative. So I'm not really sure if reconstructed you would fail to pass the bar of having a "continuity of identity" that a lot of people talk about when dealing with the concept of self. My gut says no, but I'm not sure why.