Going into deep freeze

I’m leaving tomorrow for a grand tour of Banff, then Israel, then Greece, then Princeton.  Blogging may be even lighter than usual.

In the meantime, my friend Michael Vassar has asked me to advertise the 2010 Singularity Summit, to be held August 14-15 in San Francisco.  Register now, because the summit is approaching so rapidly that meaningful extrapolation is all but impossible.

While I’m traveling, here’s a fun Singularity-related topic to discuss in the comments section: have you signed up to have your head (and possibly body) frozen in liquid nitrogen after you die, for possible Futurama-style resuscitation in the not-a-priori-impossible event that technology advances to the point where such things become possible?  Whatever your answer, how do you defend yourself against the charge of irrationality?

66 Responses to “Going into deep freeze”

  1. Matt Leifer Says:

    I have not personally signed up for cryogenics because I think that the chances that the contracts involved will be honored by a society far enough in the future to resuscitate me are pretty low. After all, we don’t have much respect for the death rites of ancient civilizations, since we display Egyptian mummies in museums.

    I think that a better bet than cryogenics would be to build a near light-speed spaceship and take a long roundtrip in it once you are diagnosed with a terminal illness. Then you could come back still alive and hopefully enough time will have passed in the Earth’s reference frame that there will either be a cure for your illness or they will be able to download your brain patterns into an AI system.

  2. fraac Says:

    The acceptance of irrationality is one of man’s greatest voyages.

  3. James Miller Says:

    I’m a member of Alcor. Not signing up for cryonics is irrational.

    Innovation comes from human intelligence. Through genetics, brain/machine interfaces/ drugs or AI we are soon likely to get enhanced human intelligence that will increase the rate of innovation. And as we get smarter, we will likely figure out better ways of getting even smarter. This will likely create a feedback loop and produce intelligences as above us as we are from ants. (We get this if we just put the software of the human brain on a computer that runs very, very fast.)

    These super-intelligences would likely master hard nanotechnology. We know some fairly serious nanotechnology is possible because bacteria can handle it. Using hard nanotechnology a super-intelligence could revive someone who has been cryogenetically preserved.

    Given that nature has given some frogs the ability to survive being frozen, why is it irrational to assume that humans might not be able to do the same?


  4. John Sidles Says:

    Who woulda thunk that a Google search for the specific phrase “Peaceful and benevolent beyond our wildest dreams” would lead to a lengthy discussion of Omega Point reincarnation by David Deutsch and Frank Tipler?

    And yet, if we ask the Ferengi question: “How does that work, exactly?” (as asked in DS9 #523), we find that Deutsch and Tipler give regrettably few details.

    That particular episode of DS9 has a fine immortality-related quote too: “He’s harmless, he’s just working on a way to become immortal”, as well as my wife’s all-purpose Star Trek favorite “How hard can it be?”

    Seeking other good-humored BibTeX entries relating to immortality/reincarnation, here are the top two (both of which you can find on-line): (#2) Ben Franklin’s epitaph, and (#1) Wallace McRae’s immortal cowboy poem Reincarnation.

    McRae does a YouTube reading of his poem that is pretty good … and IMHO the singing-physicist cowboy group Riders in the Sky covers it even better … and here the point is that if McRae’s poem makes us laugh, then perhaps we do taste immortality … for an instant, anyway. 🙂

    Given the sobering realities of a planet with 6-10 billion people on it, perhaps it is prudent to savor the various tastes of immortality that ordinary life affords … while working also to address these urgent practical realities … without waiting around (in a deep-frozen state or otherwise) for a hypothetical Omega Point transcendence to arrive.

  5. Vladimir Levin Says:

    What’s going on in Banff? I’ll be delighted to buy you a frothy beer or a tasty treat of some kind if you’re in the neighbourhood!

  6. Vladimir Levin Says:

    I guess the main question is: How much does it cost? I see no problem in someone buying a $2 lottery ticket every week despite the infinitesimal odds of winning, just because it’s nice to daydream about having all of one’s financial problems go away. Something like $2/week is a small enough amount of money that most people wouldn’t miss it.

    Getting cryogenically preserved seems akin to buying some kind of hyperball lottery ticket. Not only does the technology to wake people up out of a frozen slumber have to eventually come about, but the actual cryogenic preservation has to remain intact between now and then. Further, even if all this actually happens, the people on the other side would have to be motivated to actually bring all of their preserved ancestors back to life. Why would they do that?

    It would be neat to experience such a future, but I am not sure even I would consider the idea worthwhile of having my puny consciousness awakened! So why would “they?”

  7. Julian Says:

    We have several competing claims on our personal health budgets. There are many ways we can prolong the length and quality of our life – most of them by much smaller amounts than cryogenics offers.

    We need to evaluate them, and determine their costs (in $ and time), their potential benefits, and the chances they will succeed.

    The potential benefits of cryogenics are large, but they are dwarfed by the minuscule chance of success and the huge costs involved.

    We are better off spending the same time and money on, for example, gym membership. The expected outcome (in the statistical sense) of longevity and quality of life is much larger.

  8. gwern Says:

    > have you signed up


    > Whatever your answer, how do you defend yourself against the charge of irrationality?

    I am poor.

  9. wolfgang Says:

    I find the thought of having to live forever (or a very long time) quite frightening.
    While this fear might be irrational, I think it would be even more irrational for me to sign up.

  10. ian Says:

    I feel like i would only understand the world of The Future if i live through the years leading up to it. I Also think the right kind of life extension tech would show up sooner then when all the kinks get worked out of cryonics.

  11. Scott Says:

    Hi Vladimir,

    What’s going on in Banff?

    There’s a complexity theory shindig every couple years or so.

    I’ll be delighted to buy you a frothy beer or a tasty treat of some kind if you’re in the neighbourhood!

    Thanks so much! Alas, I just checked, and I don’t think the schedule leaves any time in Calgary (I assume that’s where you are?). Next time then!

  12. coherentsheaf Says:

    I’d rather spend cash on stuff I know I’d benefit from, rather than staking all my life on the vanishingly small probability that The Future will be a glorious utopia where frozen bodies can be revived (and that’s not preoccupied with dealing with climate change, materials shortages, etc.). Devoting one’s life savings to cryogenics seems a lot like Pascal’s wager.

  13. Greg Kuperberg Says:

    I was at the first of these cities a few months ago, but in my case it was “Banf and only Banf”.

  14. Len Ornstein Says:

    At present (and probably for the distant future) freezing bodies of humans for later resuscitation is entirely irrational.

    The rate of freezing is determined by the external temperature and the thermal conductivity of the barrier between the cooling source (e.g., liquid nitrogen – or other liquid nitrogen-cooled liquid like propane – or liquid nitrogen-cooled high-conductivity metal) and the cells to be frozen. Unless the freezing rate is enormous, the water in cells crystallizes as ice, and the ice tears up the internal structures of the cell. If the freezing rate is high enough, the water instead freezes as a glass – it vitrifies.

    At present, under the best of conditions, only very small masses of cells can be vitrified. A mass of tissue, thicker than 1 mm, will have damaging crystals form near the center. Freezing a hairless whole mouse, at best, yields only a few micrometers of vitrified cells at the surface of the skin!

    Slow freezing (especially in high concentrations of solutes – like dimethyl sulfoxide or glycerol) can cause water to be moved osmotically, to the extracellular spaces, before it freezes, and the cells may vitrify and thus avoid being cut up by intracellular crystals. Some such frozen tissues can be “revived” on melting. But such methods fail on large organisms – especially because the osmotic dehydration of complex tissues is itself very damaging.

    So much for the stupid hype about human cryopreservation (from a cell biologist who specializes in freezing tissue for preservation of cellular fine structure 😉

  15. Len Ornstein Says:

    Slow freezing of species, such as the wood frog, Rana sylvaticus, is normally followed by complete resuscitation on thawing. But this is the consequence of eons of evolutionary change in tissue solutes, and their seasonal variations. And the wood frog is only about 1 inch thick, in its smallest dimension.

  16. James Miller Says:


    Do you think that a trillion scientists working for a trillion years could figure out how to revive someone who was frozen with today’s technology?

    If your answer is yes then your objection to cryonics should come down to your objection to the singularity because it would take a post-singularity AI less than one second to accomplish what would take a trillion scientists working a trillion years to do.

  17. Oscar Cunningham Says:

    *Devoting one’s life savings to cryogenics seems a lot like Pascal’s wager.*

    I’m not sure if this counts as an example or not, but I feel like mentioning the [Pascal’s Wager Fallacy Fallacy.](http://www.overcomingbias.com/2009/03/pascals-wager-metafallacy.html)

  18. Raoul Ohio Says:

    to James Miller:

    One problem trumps all the others for civilization and the human race: overpopulation. In the event that population growth is dealt with well enough that civilization continues until technology reaches the “revive the frozen” point, why is anyone going to want to bring back extra people?

    For anyone young and/or idealistic enough to want to work on the “population issue”, you will soon discover a major obstacle: a core part of most religions is to out breed the competition; and lots of them have political clout. They attack the idea of family planning like a starving pit bull attacks a meat wagon. Good luck with that.

  19. Vladimir Levin Says:

    I found the following FAQ about cryonics.


    Among other things it pegs the costs for cryogenic preservation between about US 30k and 200k. The FAQ also states that, as a young healthy person, one can fund one’s cryogenic preservation with a life insurance policy which has a cost along the lines of a smoking habit or a cable TV subscription (so I am guessing US $50-$100/month).

    Based on this FAQ I would say it is not necessarily irrational to get frozen. But I am not sure it’s irrational *not* to get preserved either. The unknowns are just so formidable that it comes down to what you think the cumulative odds are (see my earlier comment).

    This issue reminds me of the Drake equation to determine whether or not there is intelligent life out there in the Universe. We just don’t know enough to consistently assign reasonable values to this equation. Thus, ultimately one gets whatever one wants to get out of it.

  20. James Miller Says:

    Raoul Ohio,

    The world is underpopulated compared to what would maximize the per capital wealth of mankind because lots of goods, such as software, have high fixed costs / low marginal costs. Also, the greater then number of people they more specialized we can all be. Human brains are Earth’s most valuable resource, and if we had more of them we would be richer. As evidence graph over time human population with human prosperity, or compare per capita wealth and population density of Singapore and The Congo.

    Cryonics is likely to work in a future that has cheap, powerful nanotechnology meaning it would be easy to colonize the stars.

  21. Joshua Zelinsky Says:

    The overpopulation argument has zero validity. It is extremely unlikely that if there’s a serious overpopulation problem (or any other form of resource crunch) that people will be reviving the people in cryostasis.

  22. John Sidles Says:

    Earlier this month, in Paris for a day after a conference, I toured the city in the style of a field-ecologist … which is to say, I picked a random direction, and walked a three-kilometer linear transect.

    The transect led me through the forbidding gates of the Hospitalier Sainte Anne …a five-century-old insane asylum.

    Entering with some trepidation, inside I found a huge, lovely grounds of ancient buildings and statuary … I took a portfolio of pictures showing that institution’s sobering past, and hopeful future … here is a folder with three of those pictures, titled “Gates of Sainte Anne, the Disparus, and Reanimation.”


    Inspired by what I was seeing, I sat down at the Sainte Anne cafeteria—medical center cafeterias being always a congenial place to write—and drafted for my own amusement, a program for the Year 2037 Nano-MRI Conference … that particular year being chosen as the centenary of Vladimir Arnold’s birth … seeking to answer the question “How does that work, exactly” with regard to an envisioned 2037 triumph of “Reanimation” over the memory of the “Disparus.”

    On comparing my Sainte Anne programme with the Singularity Summit programme … well … the strongest overlap is with the abstract of James Randi’s concluding address, which asserts: “Randi will argue that the inhabitants of the modern world are not as rational as they appear.”

    It is very likely, that most members of the Singularity Summit audience will agree with Randi … but how many will perceive his words as applying to themselves? That challenge is why IMHO Randi was an inspired choice as a concluding speaker.

  23. Austin Frisch Says:

    What about the small possibility that I’m revived by some kind of sadist or wake up to 1000 subjective years of indentured servitude? I’d do almost anything to avoid that, so I won’t be allowing my brain to be copied unless it’s into some kind of homomorphically encrypted container.

  24. Cyan Says:

    Not too long ago, a denizen of LessWrong made a similar inquiry on his blog. Here’s what a quick Googling of his results turns up: A survey of anti-cryonics writing, An open letter to scientific critics of cryonics. Hopefully, he’ll see this and give links to anything relevant that I missed.

  25. Joshua Zelinsky Says:

    Austin, that risk might make sense if you are extremely risk adverse, but by similar logic you might want to go kill yourself now on the off-chance that a rogue AI ends up deciding to do something similar to you in the near future.

  26. onymous Says:

    Because the world is full of AIs capable of inflicting sadistic torment on people, just waiting to go rogue? No, I think Republicans actually fail to be “artificial”, not to mention the other part.

  27. Paul Crowley Says:

    @Len Orenstein: the link in your name is broken – is this the right link?

    Your assertions seem to be contradicted by the electron micrograph and viability evidence presented in Cryopreservation of rat hippocampal slices by vitrification (Pichugin Y, Fahy GM, Morin R. Cryobiology. 2006 Apr;52(2):228-40. Epub 2006 Jan 5 doi:10.1016/j.cryobiol.2005.11.006 PMID 16403489).

    If you have a scientific case against cryonics, you’d do the world a great favour by blogging about it – as Cyan observes above, right now there’s nothing substantial and scientifically accurate on the anti side for the open-minded investigator into cryonics to read, so if you were able to change that you’d do the world a service.

  28. John Sidles Says:

    Anonymous asks (in effect): Is the world is full of AIs capable of inflicting sadistic torment on people, just waiting to go rogue?

    The Coen brothers’ recent movie A Serious Man argues that the answer is “yes.” And the “serious man” is (what else?) a quantum physicist.

    It’s best to watch this movie not as a retelling of the Book of Job—`cuz the critics got that part totally wrong IMHO—but instead as an old-fashioned zombie movie, where everyone is either (1) a full-fledged zombie, or (2) in the process of transforming into a zombie, or (3) struggling against long odds to not become a zombie.

    Except, it’s a Judaic zombie movie, so the zombies are (spiritually speaking) dybbuks. And as Coen brothers take great pains to show, the Schroedinger equation doesn’t help much against dybbuks.

    In effect, the Coen bros. movie provides grounds for skepticism regarding the Deutsch/Tipler hypothesis that post-Singularity civilizations will be “Peaceful and benevolent beyond our wildest dreams.”

    That said, Shtetl Optimized readers who like conventional zombie movies even a little bit … will purely love this Coen bros. version. 🙂

  29. Cody Says:

    I’m forgoing freezing in hopes of being resurrected as a head in a jar.

    George Foreman’s Head: It was quite a fight. And, in an interesting side note, as a floating head in a jar, I envy the dead.
    Rich Little: No arguments here.

    Though they’ve never really explained how one becomes a head in a jar—I suppose it must require freezing too (since when they forgot to feed Teller, he became nothing more than a skull).

  30. Len Ornstein Says:

    Paul Crowley;

    Your “this” is the correct link.

    The hippocampal slices used are thinner than 1mm. And only the surface layers (used for the electron micrographs) are vitrified.

    What I’ve described is well known by most who freeze tissue for light and electron microscopic study.

    I’m not ready to waste my time on a crusade against another piece of ignorant superstition.

    A search of peer reviewed journals, like Cryobiology:


    will amply support my contention.

  31. James Miller Says:


    How can you dismiss Eric Drexler’s support of cryonics as “ignorant superstition”?


    You wrote “I’m not ready to waste my time on a crusade against another piece of ignorant superstition” and yet you have so far left three comments on this post so you must have some concern for the welfare of people such as myself who are spending their own money on cryonics.

    As you are a “biologist who specializes in freezing tissue for preservation of cellular fine structure” I would be grateful if you would explain or cite something that explains why a post-singularity AI that was trillions upon trillions of times smarter than a human scientist couldn’t figure out how to revive a frozen human. I’m not asking you to go on a crusade, but rather to provide me a one sentence explanation.

    I’m writing a book on the singularity that will spend a few thousand words on cryonics and so I would be grateful for that one sentence line of help from someone of your qualifications.

  32. Paul Crowley Says:

    I’m not ready to waste my time on a crusade against another piece of ignorant superstition.

    Oddly enough, that’s what *everyone* who says it’s nonsense says. Cryonics is nothing more than ignorant superstition, but it’s superstition they can’t quite be bothered to correct. And so the reading material I can suggest for anyone taking an interest stays rather one-sided.

  33. Bill Kaminsky Says:

    Given that computational complexity is a major focus of this beloved blog, I think that perhaps the most interesting question for this fine forum to ponder is:

    Does creating an artificial neural network from a frozen brain that can emulate someone’s personality…

    or, if you prefer,

    does fixing a frozen brain via hypothetical nanotech in order that it can resume its pre-frozen personality…

    …entail any computational tasks requiring resources that scale exponentially in the number of neurons and/or neuron interconnections?

    I ask this question because if its answer is yes, then cryonic resurrection will be intractable even if cryonic organizations exist that can reliably store your frozen brain from the time you die to the time there’s trillions of benevolent, self-programming, self-reproducing, smarter-than-human artificial intelligences willing to resurrect lil’ ol’ you.

    And, alas, I have a sneaking suspicion that the answer is yes.

    Here’s the short version (I’ll neither have time for the long version tonight, nor have time to make this short version actually short and concise).

    Neural networks are “complex” in the spin-glass sense [1] of having many, many metastable states (that is, exponential in the number of neurons, but with a prefactor in the exponent significantly less than 1… for example, $2^{cn}$ with $c \alt 0.2$ [2]).

    Indeed, this sort of “complexity” is often cited as a major selling point for using neural networks for associative memories:

    a) each metastable state in principle can encode a specific memory,

    b) there’s an exponential number of metastable states, and so you can encode a lot of memories,

    c) but as there’s even exponentially more (that is, compare $2^{0.2n}$ versus $2^n$) states for the network, it shouldn’t be hard to make a network where the basins of attraction for all these metastable minima are nicely distinct and thus even asynchronous, random, noisy thermal dynamics (for example, the type in the warm goo that is you) will suffice to accurately reproduce the desired memories from faulty and/or incomplete queries being processed under random errors.

    That all sounds swell. But what if that old saw of “you only use (insert favored puny fraction) of your brain” is right in the sense that there’s many more metastable states in your brain than are ever accessed by that personality of which your family, friends, and coworkers are so fond. Now owing to the metastability, this subset of network minima that get accessed by your personality can be quite robust to the perturbations you encounter while you’re alive and kicking. But it seems plausible to me they might not be robust to the perturbation of being dead and having to have your brain emulated and rebooted. Rebooting could bring you to a whole other subset of minima that yield a markedly different personality. Having to map out all these minima is potentially a #P-hard problem, and it’s this potential that I fear is a computational complexity stumbling block to cryonic resurrection even if the technology gets invented that can perfectly extract from your frozen brain the connectivity graph of the neural network it encoded during life well as the inhibitory/excitatory proclivities of all its interconnected neurons during life [3].

    And as I write that footnote-marker “[3]”, I realize it’s now well past 3AM, and I have a f@$%ing thesis to finish (see footnote [1]) so as I can soon vow “until death do us part” to my beloved fiancée [4].

    And so I will bid y’all goodnight for the moment.


    [1] I’m a PhD student trying to illuminate the difference between adiabatic quantum computing and classical random search heuristics by considering the quantum and classical phase transitions of spin glasses (that is, by taking a randomly frustrated spin model and comparing the transitions that arise when one varies a noncommuting term at zero temperature to the transitions that arise when all terms commute but you vary the temperature). I’m also a man who sadly can’t transcend the old maxim that “If you got a hammer, everything looks like a nail.” 🙂

    [2] Not to insult anyone’s intelligence on this fine forum, but in case anyone’s wondering “\alt” is the REVTeX command for an “approximately less than” sign, i.e., “≤” but with a “~” rather than a “-” beneath the “information-theoretic death do we part”… I’ll see if my fiancée’s willing to include that in the vows… I’ll then see how she reacts if she refuses and I call her “irrational” 😉

  34. Bill Kaminsky Says:


    The footnotes didn’t render right.

    They should’ve read:


    [1] I’m a PhD student trying to illuminate the difference between adiabatic quantum computing and classical random search heuristics by considering the quantum and classical phase transitions of spin glasses (that is, by taking a randomly frustrated spin model and comparing the transitions that arise when one varies a noncommuting term at zero temperature to the transitions that arise when all terms commute but you vary the temperature). I’m also a man who sadly can’t transcend the old maxim that “If you got a hammer, everything looks like a nail.” 🙂

    [2] Not to insult anyone’s intelligence on this fine forum, but in case anyone’s wondering “\alt” is the REVTeX command for an “approximately less than” sign, i.e., “≤” but with a “~” rather than a “-” beneath the “information-theoretic death do we part”… I’ll see if my fiancée’s willing to include that in the vows… I’ll then see how she reacts if she refuses and I call her “irrational” 😉

  35. Bill Kaminsky Says:

    Ugh… the footnotes didn’t render right yet again… and all my best jokes were in them!

    One last attempt:


    [1] I’m a PhD student trying to illuminate the difference between adiabatic quantum computing and classical random search heuristics by considering the quantum and classical phase transitions of spin glasses (that is, by taking a randomly frustrated spin model and comparing the transitions that arise when one varies a noncommuting term at zero temperature to the transitions that arise when all terms commute but you vary the temperature). I’m also a man who sadly can’t transcend the old maxim that “If you got a hammer, everything looks like a nail.” 🙂

    [2] Not to insult anyone’s intelligence on this fine forum, but in case anyone’s wondering “\alt” is the REVTeX command for an “approximately less than” sign, i.e., “≤” but with a “~” rather than a “-” beneath the less than sign.]

    [3] Note this argument isn’t against the possibility in the foreseeable future of making artificial neural networks that have human or beyond-human level AI generally, but rather the possibility of inferring neural networks from frozen brains that’ll nicely reboot to the pre-frozen personality specifically.

    [4] Yes, yes… enlightened couples today should all vow “until information-theoretic death do we part”… I’ll see if my fiancée’s willing to include that in the vows… I’ll then see how she reacts if she refuses and I call her “irrational” 😉

  36. John Sidles Says:

    Bill (Kaminsky), your post was *very* interesting … and good luck finishing your thesis …

    Uhh … and as a person married for 30+ years … it might be prudent to get eight hours of sleep before using the word “irrational” around your fiancé … just trust someone who’s been there. 🙂

    Your post suggests *new* approaches to a challenge that a lot of people (including Scott and his MIT colleagues) have started thinking about in broader terms than hitherto. That challenge has two parts: (1) Exhibit any experimental or observational dataset—in effect, an oracle—that provably cannot be simulated in PTIME with classical computational resources. (2) Alternatively, provide direct experimental evidence that the geometry of Nature’s state-space obstructs such a demonstration, and describe that geometry.

    Here the idea is to untether quantum information science (QIS) from quantum computing, by broadening the focus of experimental QIS to include oracle devices of all kinds. Bill, what your post (and thesis?) points out is that any such broadening of QIS would logically encompass AI devices in their classical, quantum, and hybrid embodiments … which is an interesting idea, and a provocative broadening.

    The key phrase in part (1) of the challenge is “provably cannot be simulated” … this sounds like what you are grappling with in your thesis, and it is of course a key issue for the whole Singularity/Transhumanist programme.

  37. Len Ornstein Says:

    James Miller:

    Since no ‘scientific model’ can be proved to be either absolutely true – or absolutely false, you’re entitled to believe that what currently appear to be extremely improbable models will nonetheless eventually receive significant support.

    That’s a costly (not a very efficient) survival strategy, but your welcome to pursue. I call that kind of approach, “ignorant” and “superstitious”. It’s usually largely motivated by wishful thinking 😉

    If you ignore Drexler’s comment, you’ll find support for my ‘position’ further down in the link you provided.

  38. Joshua Zelinsky Says:

    Do you think that a trillion scientists working for a trillion years could figure out how to revive someone who was frozen with today’s technology?

    If your answer is yes then your objection to cryonics should come down to your objection to the singularity because it would take a post-singularity AI less than one second to accomplish what would take a trillion scientists working a trillion years to do.

    I don’t think this argument holds water. First of all, you seem to be making an estimate that isn’t justified even if one accepts a Singularity event (really? That would be less than a second? Under what basis?). Also, even if that event will occur, if it occurs comparatively late, there’s a non-trivial probability that something will go wrong with the cryonic preservation, due to either technological failure or societal failure such as the cryonic institutions going bankrupt, or laws being passed against cryonics. These aren’t as unlikely as they might seem at first glance. The first has occurred in the past, although cryonic organizations now have better structured finances. The second has not happened outright but at least one area, British Columbia, has passed laws against cryonic preserving individuals (although nothing in the law functions against continuing to preserve the already preserved). So even if the Singularity does occur, if it occurs 50 or a 100 years from now, there’s a serious chance that preservation won’t last that long.

  39. James Miller Says:


    I’m assuming that a singularity would create computers that have speeds near the physical limit of computation, and this is so much faster than the speed at which a human processes that a post-singularity AI would be trillions upon trillions upon trillions of times faster than a human.

    You are right that a cryonics organization might not survive even another 50 years so even if we assume that a post-singularity AI would revive we can’t be sure that cryonics would work. But the chance of a cryonics organization being able to keep you preserved for another 50 or 100 years seems high enough to make signing up for cryonics an extremely good bet, so if you think cryonics is irrational you must believe that either there won’t be a singularity in the next 100 years or that the post-singularity world won’t want to revive you.

  40. John Sidles Says:

    James Miller says: If you think cryonics is irrational you must believe that either there won’t be a singularity in the next 100 years ,,,

    Soberingly, the evidence that there isn’t a singularity in the offing is stronger than the friends of STEM would prefer. See, e.g., “The New Age”, which was the cover story for Time Magazine of April 29, 1957.

    The point conveyed by this the 53-year-old article is that the STEM vision really hasn’t changed much in the past half-century. What is sobering is that, although STEM progress has continued, STEM acceleration has slowed … indeed, per-capita STEM enrollment in North America has declined steadily since the 1960s.

    Really, are Boeing 787s all that different from 707s? Is the Hubble Space telescope all that different from the Keyhole satellites of the 1950s? The point being that quite a few of the technologies envisioned in the 1950s saturated their technical bounds within a few decades … with the result that we never did get those nuclear-powered flying cars.


    James Miller says: … or that the post-singularity world won’t want to revive you.

    Soberingly, the foundational belief of that future societies will be “Peaceful and benevolent beyond our wildest dreams” too finds sparse support in game theory, anthropology, cognitive science, history, or evolutionary biology.

    This point is not that a “singularity that is peaceful and benevolent beyond our wildest dreams” couldn’t happen, but rather, available evidence suggests that this outcome is far from inevitable, and to achieve anything like it will require a stronger-than-usual admixture of foresight, discipline, hard work, creativity … and luck.

  41. Raoul Ohio Says:

    James M.:

    There may well be a singularity in the next 100 years. If so, I doubt it will be what you are expecting.

  42. asdf Says:

    585 bucks to sign up for that summit! It would be nice if you mentioned that in your post. I wouldn’t have bothered clicking through their expired SSL certificate to see the registration form if I’d known.

  43. John Sidles Says:

    ST:DS9 episode #121: “In the Cards”
    Cadet Nog: It’s not my fault your species decided to abandon currency-based economics in favor of some philosophy of self-enhancement.

    Jake Sisko: Hey – watch it! There’s nothing wrong with our philosophy. We work to better ourselves and the rest of Humanity.

    Cadet Nog: What does that mean, exactly?

    Jake Sisko: It means… it means, we don’t need money.

  44. Sandra T. Says:

    Don’t you have better uses for your money than spending $30+K on a lottery ticket with extremely poor chances of success. Even if the chances were much better, wouldn’t you still have better uses for your money? Cryogenics could only be a rational expense if you only cared about yourself and your own survival. I know I have bigger concerns and I think that most people are not so selfish.

    That $30K can instead go towards your kids’ college educations, to improve their quality of life. Or, donate it to a charity to help somebody else’s kids. Cryogenics is only a rational use of discretionary funds if you are incredibly selfish, to the limits of economists’ imaginations, and don’t care about your family or society. There are better ways of living forever.

  45. John Sidles Says:

    Sandra T’s post had eight well-crafted sentences, and every single sentence made an independent thought-provoking point. Great post.

    Sandra, any enterprise, career, or community that you commit to, will be lucky (IMHO) to have you on-board.

  46. Joshua Zelinsky Says:

    Sandra, given that people are going to spend a lot of money selfishly, why not spend it on cryonics? Most of your argument is just as much an argument against spending it on a boat or a fancy car.

    Len, I’m going to agree with requests for you to write something summarizing more accurately what is wrong with cryonics. Simply dismissing it as you not having time to write about it isn’t helpful for those of us who are on the edge and are thinking of signing up but aren’t sure. It likely wouldn’t take that much time for you to write up something on this subject and you are clearly a subject matter expect. I’d be one who’d be very grateful to read what you have to say on the matter.

  47. Paul Crowley Says:

    Don’t know why this didn’t get posted last time, but: Orenstein’s claim seems to be that vitrifying something the size of a brain is impossible. Here’s an electron micrograph from Alcor that might help evaluate that claim.

  48. John Sidles Says:

    This is one of those subjects that is sufficiently rich that (in Scott’s phrase) there is a huge amount of “talking-past-each-other.”

    I had an experience that is relevant to the social and technical context of cryo-preservation.

    Once upon a time, in the equatorial Pacific, I was stuck on a remote outer island … so poor that the people there had as resources only sunlight, water, air, sand … and themselves. Does this sound familiar? That’s because these are pretty much the only resources that our planet has in abundance.

    There was a cryo-preservation facility on that island … for tuna, not for people. But that cryo-facility was not in good shape, because when the islands came under economic and ecological stress, maintaining that cryo-facility was not their highest priority.

    So perhaps the biggest risk factor for cryo-reservation has nothing to do with vitrification versus the lack-of-same, but instead is that by the end of the 21st century, our planet will have 10 billion people on it, who will be under sufficient economic and ecological stress, that preserving the frozen heads of people who are no longer remembered, will not have a high social priority.

    For me, creating new resources to avert this dystopian outcome is what quantum systems engineering is mainly all about … recognizing that quantum information science is good for many other things too.

  49. Len Ornstein Says:

    Paul Crowley, Comment #47:

    The Alcor micrograph is completely inadequate to judge the quality of preservation (e.g., no neurons, neuron nuclei, neuron mitochondria – and the internal fine structure – are detectable). But even if they were well preserved, they would have to prove that the section came from deep within a whole brain – rather than from very near the surface!

    The fact that they don’t even address such problems when they ‘present evidence’ should create suspicion that this is intentional hype.

  50. Raoul Ohio Says:

    A couple of years ago I read a long article about the bizarre world of cryogenics, perhaps in the “New Yorker” or “Wired”. Does anyone have a reference to that?

    To assess your chances of being successfully unfrozen, check out the story of American baseball legend Ted Williams.

    Googling on ‘cyro + “ted williams”‘ brings up about 3k hits. Following are brief quotes from two of them.

    http://sportsillustrated.cnn.com/baseball/news/2003/08/12/williams_si/ :

    “Williams’ head has been shaved and drilled with holes. Verducci also reports that, before the head was placed in its present location, it was accidentally cracked as many as 10 times due to fluctuating storage temperatures. ”

    http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=103×485544 :

    “Workers at an Arizona cryonics facility mutilated the frozen head of baseball legend Ted Williams – even using it for a bizarre batting practice, a new tell-all book claims.

    In “Frozen,” Larry Johnson, a former exec at the Alcor Life Extension Foundation in Scottsdale, Ariz., graphically describes how The Splendid Splinter” was beheaded, his head frozen and repeatedly abused.

    The book, out Tuesday from Vanguard Press, tells how Williams’ corpse became “Alcorian A-1949″ at the facility, where bodies are kept suspended in liquid nitrogen in case future generations learn how to revive them.

    Johnson writes that in July 2002, shortly after the Red Sox slugger died at age 83, technicians with no medical certification gleefully photographed and used crude equipment to decapitate the majors’ last .400 hitter.

    Williams’ severed head was then frozen, and even used for batting practice by a technician trying to dislodge it from a tuna fish can.”

  51. Pozorvlak Says:

    Dr Ornstein: I’m no cryonics advocate, but your claims seem to be a few years out of date.

    As far as I can tell, you’re claiming three things:

    1) That quick freezing of tissue without cryoprotectants will cause catastrophic ice damage.
    2) That vitrification is only possible for tissue samples less than 1mm in thickness.
    3) That slow freezing is possible for larger samples, but causes catastrophic osmotic damage.

    Nobody’s disputing claim 1. However, a search for “whole organ vitrification” on Google Scholar turns up the following papers:

    “Cryopreservation of organs by vitrification: perspectives and recent advances”, Fahy et al, 2004 (link)

    “Cryopreservation of the ovary by vitrification as an alternative to slow-cooling protocols”, Coubiere et al, 2006 (link)

    The first paper (unfortunately paywalled) discusses various experiments on vitrifying whole rabbit kidneys; the second discusses vitrification of sheep ovaries. I could be misreading the paper (I’m not a biologist), but AFAICT they had no difficulty vitrifying the ovaries; there are some graphs comparing levels of tissue damage in vitrified and non-vitrified ovaries. There’s also

    “Cryopreservation of complex systems: slow freezing has not had its day yet”, Dittrich et al, 2007 (link)

    (again paywalled), which discusses the use of slow freezing with cryoprotectants to preserve swine uteri, with, again, some viability post-thaw.

    It’s entirely possible I’ve misunderstood these papers – I’m not a biologist, as I said before. But let me add my voice to those calling on you to write up your claims in a bit more detail! I think the papers above at least show that there’s a case to answer here.

  52. Pozorvlak Says:

    Of course, ovaries, kidneys and uteri are not brains, and the preservation requirements for brains are no doubt more stringent. But many of those signing up for cryonics now won’t die for decades, and cryopreservation tech will likely improve in the meantime, unless there’s some fundamental obstacle blocking progress, as you claim.

  53. Raoul Ohio Says:

    For anyone finding themselves driving accross the mountains on Canada 1, note that there two towns: Banff and Lake Louise. My first time, going from Ohio to Hawaii, by a piece of bad luck happened to be Canada Day. Pulling into Banff, I made a snap judgement: “this is a big money version of Gatlinsburg”. At this point a horse drawn tourist bus was coming the other way, giving me a chance to do a U-turn and head west. Lake Louise, about as awesome as Crested Butte, is more nature and camping oriented. Everyone working there it too pleasant to believe. Also, you can take the Icefield Parkway, a modern highway running about 150 miles NW along the continental divide up to Jasper. As an example of the coolness of the IFP, there are handicaped accessable trails along the treeline. And you can pull off the road and climb to the top of mountains in a half hour.
    Check it out.

  54. Len Ornstein Says:

    Pozorvlak, #51 & 52:

    The methodologies in your link references are defective in a number of ways.

    For example: Coubiere et al (your second link) fail to appreciate that you can’t take a frozen tissue and fix it in an aqueous fixative (e.g., Bouin’s solution) and expect to be able to assess damage with any accuracy – because the distribution of ice, and the displacements it produce, get wiped out by the fixative.

    Proper evaluation requires either so-called freeze-substitution/fixation (where ice is dissolved with a solvent, like acetone or acetonitrile, at a temperature below about 40ºC, and then the tissue is fixed with a solution of about 70% acetonitrile + 25% water + 5% glutaraldehyde); or freeze drying followed by an ‘anhydrous’ (less than 30% water) fixation.

    As I noted, (#15), the wood frog kind of model is interesting, and the papers you link to are trying to extend those observations to mammalian organs.

    This is certainly worth doing, but those papers don’t represent ‘success’. And they have no relevance to Alcor-type freezing of whole heads or bodies – in anticipation of ‘revival’ at some future date!

  55. John Sidles Says:

    Craig Venter has pretty good broad-spectrum definition of synthetic biology, “software that builds its own hardware.”

    Building on this definition, we can (roughly) envision a reanimation process in which a (heavily damaged) frozen brain is disassembled layer-by-layer, by some vaguely imagined synthetic biological means, while simultaneously an abstract model of its cognitive capacity is built-up … that cognitive model being extracted from the disassembled tissues, and subsequently instantiated in either a physical biological body, or a virtual one.

    For anything like this optimistic scenario to become a reality, radical advances in nano-technology, synthetic biology, and (what might be called) synthetic cognition all are required.

    Far be it from me to condemn radical optimism … but to make any of these envisioned capabilities become practical realities, we had all better be prepared to work radically hard. Because these aren’t capabilities that can be achieved by a handful of “breakthroughs” (alone) … or by a handful of people (working alone) … they are the aggregate of innumerable practical advances … and these practical advances in turn require a large community of motivated, hard-working, well-organized people.

    It’s seems to me, that creating and sustaining large communities of motivated, hard-working, well-organized people, is the single hardest aspect of creating regenerative biomedical technologies of every description.

    As one of my professors was fond of saying, “Once you have a good idea, then your job is zero percent of the way done.”

    But heck … this is just another way of expressing a mathematical tautology: at any given moment, we are zero percent of the way to achieving the Singularity! So how do we measure our progress? And how do we recognize obstructions? 🙂

  56. Sid Says:

    Hey Scott,

    Apparently there’s a possible proof of P \neq NP floating around. It’s been blogged about here


    and according to that post, it seems that Stephen Cook thinks it’s a “relatively serious claim to have solved P vs NP.”

    Care to comment?

  57. Anon Says:

    Will you be at Tel Aviv Uni? Will you do a lecture there?

  58. matt Says:

    Reasons to guess the proof is wrong:

    1)It’s not written in latex.

    2)I think proving P \neq PSPACE or NL \neq NP would already get you a Godel prize and a Turing award. As someone said in some similar context, proving results like those two would already be “blue sky”, while proving P vs NP is “Andromeda galaxy” in comparison. Walk before you run, and all that.

  59. onymous Says:

    “Not in Computer Modern typeface” != “not written in LaTeX”. Looks like it was to me.

  60. matt Says:

    (1) was a joke.

  61. Scott Says:

    Anon 57: I just lectured at Tel Aviv U in January! Not sure about this visit.

  62. Warren Henning Says:

    Scott, when you get a chance, this alleged proof that P != NP would be a good topic for you to discuss.

  63. Pozorvlak Says:

    Len Ornstein: Thanks!

    My first link (to the Fahy paper) appears to be broken: this one will hopefully work better.

  64. Kaminsky-responder Says:

    BILL KAMINSKY your post was interesting. Why don’t you start a blog too? I’d read it.

    I did wonder what the \alt was, so it was a relief when you included that datum in your footnotes. I like it when authors pay attention to my needs. 🙂

  65. Sidles-responder Says:

    If we were frozen now and woken up several megacenturies later, might we be able to adapt to the environment?

    I think the synthetic bio approach might be the way to go. Instead of freezing, try digitizing and saving and then regrowing according to the saved info.

    I wonder if there is a way to crawl the network that is the brain using some sort of a bug (motile bacteria?) and record its connectivity. Might we might also need to know the potency of various neural types in producing certain transmitters? For example, this might encode the strength of emotions we feel in response to events—something not encoded in the topology.

    Is there anybody working on this problem of a fast and accurate way of mapping the topology of the brain?

  66. Bill Kaminsky Says:

    To Kaminsky-Responder (#64):

    Aw shucks… I’m flattered. 🙂

    And, just in case you Googled my name, I am indeed the Bill Kaminsky who used to write:


    Maybe I should start blogging again. Hmmm… but can I honestly expect to avoid the peril so poignantly depicted in this xkcd: http://xkcd.com/386/ ?! I think not. 🙂


    And now to everyone on this blog still thinking about computational complexity obstacles to cryonics (which I doubt is all that many people given all the focus now on Deolaikar’s P vs. NP proof)…

    I should amend the comments I made (#33 and 35) with the following one.

    While randomly-generated neural networks are generically “complex” in the sense I mentioned (comment #33) of having a number of metastable states growing exponentially in the number of neurons, it’s quite possible our brains might be much “simpler” neural networks encoding only a polynomial number of metastable states. (NB: Given that we have something like 10^11 neurons, this would still should be a humongous number!)

    Indeed, in the most popular models of neural networks that statistical physicists play with, one aims to avoid complexity in the sense I mentioned and instead figure out a way to plant just a linear number of desired metastable states and ensure there aren’t any other metastable states to get in the way of the dynamics reaching the desired metastable states.

    To the best my knowledge, no one’s ever written down a model that allows one to plant a superlinear number of desired metastable states without having unwanted metastable states get in the way.

    Now, correct me if I’m wrong, but there’s no scientifically consensus yet how the human brain’s neurons wire together specifically to encode memories and behaviors, is there?

    As such, I don’t think we’re able to distinguish presently between the following 2 possibilities:

    1) Your brain requires its neurons to be wired together in some specific way so that a priori there’s a known set of metastable states. This is something that well might restrict the number of metastable states to be linear (or at most polynomial) in the number of neurons. Personality-preserving, post-mortem reconstruction of the neural network your dead, frozen brain encoded when it was warm and alive could thus in principle be a computationally tractable task.


    2) Your brain can manage just fine with its neurons being wired together quasi-randomly. Yeah, there’s an absurdly large set of metastable states: one exponentially large in the number of neurons. Yet somehow, your brain manages to isolate some teeny-tiny fraction of these metastable states to use to encode your memories and behaviors. But the teeny-tinyness of this fraction that gets used makes personality-preserving, post-mortem reconstruction of/from frozen brains then seem computationally intractable even with computers trillions and trillions of times faster than those today.