Timeless Identity

1Eliezer_Yudkowsky03 June 2008 08:16AM

This post is part of the Quantum Physics Sequence.
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.

Comments (75)

Roland203 June 2008 09:03:28AM0 points [-]

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

mitchell_porter203 June 2008 09:23:53AM0 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.

Eliezer_Yudkowsky03 June 2008 09:30:59AM0 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.

Frank_Hirsch03 June 2008 09:32:58AM0 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.

devicerandom03 June 2008 09:38:58AM0 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?

Eliezer_Yudkowsky03 June 2008 09:39:03AM0 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.

mitchell_porter203 June 2008 09:47:00AM0 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?

Eliezer_Yudkowsky03 June 2008 09:50:19AM0 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.

mitchell_porter203 June 2008 10:01:57AM0 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.

MichaelAnissimov03 June 2008 10:44:18AM0 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.

Robin_Brandt03 June 2008 11:10:21AM1 point [-]

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!

IL03 June 2008 11:32:12AM1 point [-]

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.

Will_Pearson03 June 2008 11:52:11AM0 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.

Unknown03 June 2008 12:34:46PM0 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.

Kaj_Sotala03 June 2008 12:46:01PM0 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.

Ian_Maxwell03 June 2008 01:52:08PM0 points [-]

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?

Doug_S.03 June 2008 02:46:46PM0 points [-]

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.)

gwern21 June 2009 01:07:28AM1 point [-]

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?)

TGGP403 June 2008 02:47:26PM0 points [-]

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

iwdw03 June 2008 02:53:06PM0 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...)

Brandon_Reinhart03 June 2008 03:24:53PM0 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?

David_Solomon03 June 2008 03:36:13PM0 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?

Constant203 June 2008 04:32:32PM0 points [-]

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

I spy with my little eye something beginning with D.

poke03 June 2008 04:39:38PM0 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.

Robin_Brandt03 June 2008 04:42:05PM0 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...

michael_vassar303 June 2008 05:13:00PM1 point [-]

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.

Wiseman03 June 2008 05:14:54PM0 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.

RobinHanson03 June 2008 05:22:06PM1 point [-]

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.

Eliezer_Yudkowsky03 June 2008 05:33:26PM1 point [-]

@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.

Unknown03 June 2008 05:55:59PM0 points [-]

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.

Sebastian_Hagen203 June 2008 05:57:40PM0 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.

Roland203 June 2008 05:58:01PM0 points [-]

Eliezer,

ok, thanks for the link.

DaveInNYC03 June 2008 05:59:53PM0 points [-]

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).

HalFinney03 June 2008 06:16:46PM0 points [-]

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.

iwdw03 June 2008 06:36:20PM0 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.

Patrick_(orthonormal)03 June 2008 06:59:46PM1 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.

Roko03 June 2008 07:13:30PM0 points [-]

Just thought I'd mention that if one wants to consider parfit's thought experiment (the brain scanner that non-destructively copies you) and the underlying quantum mechanical nature of reality, you have to remember the no-cloning theorem.

http://en.wikipedia.org/wiki/No_cloning_theorem

Thus if you consider yourself to be a specific quantum state, parfit's machine cannot possibly exist. Of course there are subtleties here, but I just though I'd throw that in for people to consider.

Nick_Tarleton03 June 2008 07:25:48PM0 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.

Kaj_Sotala03 June 2008 07:46:54PM0 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.

Wiseman03 June 2008 08:13:24PM0 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.

Nick_Tarleton03 June 2008 08:20:53PM0 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.

Kaj_Sotala03 June 2008 08:31:26PM0 points [-]

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.

Wiseman03 June 2008 08:58:19PM0 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.

Recovering_irrationalist03 June 2008 09:35:03PM0 points [-]

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?

Recovering_irrationalist03 June 2008 09:39:13PM0 points [-]

(Assume Adam's a Xeroxphobe)

Brandon_Reinhart03 June 2008 10:07:02PM0 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.

David_Solomon03 June 2008 10:13:18PM0 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?

JulianMorrison03 June 2008 10:32:19PM0 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.

Patrick_(orthonormal)03 June 2008 10:36:23PM0 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.

David_Solomon03 June 2008 10:41:21PM0 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?

Caledonian203 June 2008 10:54:45PM0 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.

03 June 2008 11:08:00PM0 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).

Recovering_irrationalist03 June 2008 11:19:00PM0 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.

John_Faben04 June 2008 12:33:00AM0 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?

Phil_Goetz04 June 2008 01:25:00AM0 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.

Court04 June 2008 01:27:00AM0 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 .

Peter604 June 2008 02:30:00AM0 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.

Nick_Tarleton04 June 2008 02:55:00AM0 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.

Allan_Crossman04 June 2008 03:06:00AM0 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.

Eliezer_Yudkowsky04 June 2008 03:56:00AM0 points [-]

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

Ben_Wraith04 June 2008 04:03:00AM0 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.

Erik_Mesoy04 June 2008 05:54:00AM0 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?

Sebastian_Hagen204 June 2008 07:28:00AM0 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).

Will_Pearson04 June 2008 07:31:00AM0 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.

Court04 June 2008 08:58:00AM0 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?

Tim_Tyler04 June 2008 10:11:00AM0 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.

Günther_Greindl04 June 2008 10:33:00AM0 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


steven04 June 2008 01:10:00PM0 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)?

Will_Pearson04 June 2008 10:13:00PM0 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.

Nick_Tarleton04 June 2008 10:32:00PM0 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.

Psy-Kosh04 June 2008 10:34:00PM0 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?)

Aaron705 June 2008 12:05:00AM0 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.

Hopefully_Anonymous312 June 2008 08:09:00AM0 points [-]

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.

Eymer24 June 2008 06:33:00PM0 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 ?

Jonii08 October 2009 07:46:33PM1 point [-]

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