(This was originally a link to a post on my blog, A survey of anti-cryonics writing. Eliezer asked me to include the entire text of the article here.)
For its advocates, cryonics offers almost eternal life. To its critics, cryonics is pseudoscience; the idea that we could freeze someone today in such a way that future technology might be able to re-animate them is nothing more than wishful thinking on the desire to avoid death. Many who battle nonsense dressed as science have spoken out against it: see for example Nano Nonsense and Cryonics, a 2001 article by celebrated skeptic Michael Shermer; or check the Skeptic's Dictionary or Quackwatch entries on the subject, or for more detail read the essay Cryonics–A futile desire for everlasting life by "Invisible Flan".
That it seems so makes me sad, because to my naive eyes it seems like it might work and I would quite like to live forever, but I know that I don't know enough to judge. The celebrated Nobel prize winning physicist Richard Feynman tells a story of a US general who spoke to him at a party and explained that one big challenge in desert warfare is keeping the tanks fuelled given the huge distances the fuel has to travel. What would really help, the general said, would be if boffins like Feynman could invent a sort of engine that was powered by sand. On this issue, I'm in the same position as the general; in the same way as a tank fuelled by sand seems plausible enough to him, it makes sense to me to imagine that however your brain stores information it probably has something to do with morphology and chemistry, so there's a good chance it might not evaporate right away at the instant of legal death, and that freezing might be a way to keep the information there long enough for future societies to extract it with their future-technology scanning equipment.
And of course the pro-cryonics people have written reams and reams of material such as Ben Best's Scientific Justification of Cryonics Practice on why they think this is exactly as plausible as I might think, and going into tremendous technical detail setting out arguments for its plausibility and addressing particular difficulties. It's almost enough to make you want to sign up on the spot.
Except, of course, that plenty of totally unscientific ideas are backed by reams of scientific-sounding documents good enough to fool non-experts like me. Backed by the deep pockets of the oil industry, global warming denialism has produced thousands of convincing-sounding arguments against the scientific consensus on CO2 and AGW. Thankfully in that instance we have blogs like Tim Lambert's Deltoid, RealClimate, and many others tracking the various ways that the denialists mislead, whether through cherry-picking evidence, misleading quotes from climate scientists, or outright lies. Their hard work means that denialists can barely move or speak without someone out there checking what they have to say against science's best understanding and pointing out the misrepresentations and discrepancies. So before I pony up my £25 a month to sign up to cryonics life insurance, I want to read the Deltoid of cryonics - the articles that take apart what cryonics advocates write about what they do and really go into the scientific detail on why it doesn't hang together.
Here's my report on what I've found so far.
Nano Nonsense and Cryonics goes for the nitty-gritty right away in the opening paragraph:
To see the flaw in this system, thaw out a can of frozen strawberries. During freezing, the water within each cell expands, crystallizes, and ruptures the cell membranes. When defrosted, all the intracellular goo oozes out, turning your strawberries into runny mush. This is your brain on cryonics.
This sounds convincing, but doesn't address what cryonicists actually claim. Ben Best, President and CEO of the Cryonics Institute, replies in the comments:
Strawberries (and mammalian tissues) are not turned to mush by freezing because water expands and crystallizes inside the cells. Water crystallizes in the extracellular space because more nucleators are found extracellularly. As water crystallizes in the extracellular space, the extracellular salt concentration increases causing cells to lose water osmotically and shrink. Ultimately the cell membranes are broken by crushing from extracellular ice and/or high extracellular salt concentration. [...] Cryonics organizations use vitrification perfusion before cooling to cryogenic temperatures. With good brain perfusion, vitrification can reduce ice formation to negligible amounts.
Best goes on to point out that the paragraph I quote is Shermer's sole attempt to directly address the scientific claims of cryonics; once the opening paragraph has dispensed with the technical nitty gritty, the rest of the piece argues in very general terms about "[blind] optimistic faith in the illimitable power of science" and other such arguments. Shermer received many other responses from cryonics advocates; here's one that he considered "very well reasoned and properly nuanced".
The Quackwatch entry takes us little further; it quotes the debunked Shermer argument above, talks about the cost (they all talk about the cost and a variety of other issues, but here I'm focussing specifically on the issue of technical plausibility), and links to someone else making the same already-answered assertions about freezing damage.
The Skeptic's Dictionary entry is no advance. Again, it refers erroneously to a "mushy brain". It points out that the technology to reanimate those in storage does not already exist, but provides no help for us non-experts in assessing whether it is a plausible future technology, like super-fast computers or fusion power, or whether it is as crazy as the sand-powered tank; it simply asserts baldly and to me counterintuitively that it is the latter. Again, perhaps cryonic reanimation is a sand-powered tank, but I can explain to you why a sand-powered tank is implausible if you don't already know, and if cryonics is in the same league I'd appreciate hearing the explanation.
It does link to the one article I can find that really tries to go into the detail: Cryonics–A futile desire for everlasting life by "Invisible Flan". It opens on a curious note:
If you would like my cited sources, please ask me and I will give them to you.
This seems a very odd practice to me. How can it make sense to write "(Stroh)" in the text without telling us what publication that refers to? Two comments below ask for the references list; no reply is forthcoming.
And again, there seems to be no effort to engage with what cryonicists actually say. The article assets
it is very likely that a human would suffer brain damage from being preserved for a century or two (Stroh).
This bald claim backed by a dangling reference is, to say the least, a little less convincing than the argument set out in Alcor's How Cold is Cold Enough? which explains that even with pessimistic assumptions, one second of chemical activity at body temperature is roughly equivalent to 24 million years at the temperature of liquid nitrogen. Ben Best quotes eminent cryobiologist and anti-cryonics advocate Peter Mazur:
...viscosity is so high (>1013 Poise) that diffusion is insignificant over less than geological time spans.
Another part of the article points out the well-known difficulties with whole-body freezing - because the focus is on achieving the best possible preservation of the brain, other parts suffer more. But the reason why the brain is the focus is that you can afford to be a lot bolder in repairing other parts of the body - unlike the brain, if my liver doesn't survive the freezing, it can be replaced altogether. Further, the article ignores one of the most promising possibilities for reanimation, that of scanning and whole-brain emulation, a route that requires some big advances in computer and scanning technology as well as our understanding of the lowest levels of the brain's function, but which completely sidesteps any problems with repairing either damage from the freezing process or whatever it was that led to legal death.
Contrast these articles to a blog like Deltoid. In post after painstaking post, Lambert addresses specific public claims from global warming denialists - sometimes this takes just one graph, sometimes a devastating point-by-point rebuttal.
Well, if there is a Tim Lambert of cryonics out there, I have yet to find them, and I've looked as best I can. I've tried various Google searches, like "anti-cryonics" or "cryonics skeptic", but nearly all the hits are pro-cryonics. I've asked my LiveJournal friends list, my Twitter feed, and LessWrong.com, and found no real meat. I've searched PubMed and Google Scholar, and again found only pro-cryonics articles, with the exception of this 1981 BMJ article which is I think more meant for humour value than serious argument.
I've also emailed every expert I can find an email address for that has publically spoken against cryonics. Sadly I don't have email addresses for either Arthur W. Rowe or Peter Mazur, two giants of the cryobiology field who both have strongly anti-cryonics positions; I can only hope that blog posts like these might spur them into writing about the subject in depth rather than restricting themselves to rather brief and unsatisfactory remarks in interviews. (If they were to have a change of heart on the subject, they would have to choose between staying silent on their true opinions or being ejected from the Society for Cryobiology under a 1982 by-law.) I mailed Michael Shermer, Steve Jones, Quackwatch, and Professor David Pegg. I told them (quite truthfully) that I had recently started talking to some people who were cryonics advocates, that they seemed persuasive but I wasn't an expert and didn't want to fall for a scam, and asked if there was anything they'd recommend I'd read on the subject to see the other side.
The only one of these to reply was Michael Shermer. He recommended I read David Brin, Steve Harris and Gregory Benford. This is a pretty surprising reply. The latter two are cryonics advocates, and while Brin talks about a lot of possible problems, he agrees with cryonics advocates that it is technically feasable.
I expanded my search to others who might be knowledgable: Society of Cryobiology fellows Professor Barry Fuller and Dr John G Baust, and computational neuroscience Professor Peter Dayan. I received one reply: Dayan was kind enough to reply very rapidly, sounding a cautionary note on how much we still don't know about the structure of memory and referring me to the literature on the subject, but was unable to help in my specific quest for technical anti-cryonics articles.
In his 1994 paper The Molecular Repair of the Brain, cryptology pioneer Professor Ralph Merkle remarks
Interestingly (and somewhat to the author's surprise) there are no published technical articles on cryonics that claim it won't work.
Sixteen years later, it seems that hasn't changed; in fact, as far as the issue of technical feasability goes it is starting to look as if on all the Earth, or at least all the Internet, there is not one person who has ever taken the time to read and understand cryonics claims in any detail, still considers it pseudoscience, and has written a paper, article or even a blog post to rebut anything that cryonics advocates actually say. In fact, the best of the comments on my first blog post on the subject are already a higher standard than anything my searches have turned up.
If you can find any articles that I've missed, please link to them in the comments. If you have any expertise in any relevant area, and you don't think that cryonics has scientific merit - or if you can find any claim made by prominent cryonics advocates that doesn't hold up - any paragraph in Ben Best's Scientific Justification of Cryonics Practice, anything in the Alcor Scientists’ Cryonics FAQ or the Cryonics Institute FAQ, or anything in Whole Brain Emulation: A Roadmap (which isn't directly about cryonics but is closely related) - then please, don't comment here to say so. Instead, write a paper or a blog post about it. If you don't have somewhere you're happy to post it, and if it's better than what's already out there, I'll be happy to host it here.
Because as far as I can tell, if you want to write the best anti-cryonics article in the world, you have a very low bar to clear.
Related articles: Carl Schulman links to Robin Hanson's What Evidence in Silence or Confusion? on Overcoming Bias, which discusses what conclusions one can draw from this.
The allegation that cryonics is pseudoscience reminds me of the allegations that Singularitarianism/Transhumanism are "atheist religion", "the rapture for nerds", etc. That confusion, I think, comes when people see the questions we're investigating — "Could we live forever?", "Could we end suffering?", etc. — and assume that we're answering the questions in a way similar to how religion does... or they don't even think to remember why they believe religion is bad, and they assume that it's the questions rather than the answers. Obviously, the problem with religion isn't the questions it asks, nor their motives for asking those questions; the problem is the way religion acquires answers to those questions. The same applies to seeking eternal life. Eternal life as a goal isn't wishful thinking; it's wishful thinking when people mistakenly believe that the goal is easy or has already been reached ("you can live forever if you believe in Jesus", etc.). Yet it's not surprising that many perfectly intelligent people buy into these memes. They are used to hearing completely bullshit answers to these completely legitimate questions, so they... (read more)
If you think that the Apollo program was better supported by missile evidence than cryonics is by the rabbit kidney vitrification, you're going to have to show your workings. You should do so in more than a comment, though, since whatever you post will as I show above be the best anti-cryonics article in the world.
That is not the most common usage here. See Three Singularity Schools and the LW wiki page.
EDIT: The parent comment does not deserve to be at -4. This is a reasonable thing for an inexperienced commenter to say.
Yes, getting hugely tangled up in meta-level arguments instead of looking at the actual arguments and evidence and object-level way-the-world-is would indeed be a classic blunder.
This is the best anti-cryonics argument I've heard so far. I largely agree with the replies about why it's wrong, but at least it's an argument rather than a gut "ewww..." or "blasphemy!" or "crazy talk!" reaction.
Your reply really is excellent!
Still - and I've been noting this a lot - not to do with technical feasibility. A word I have finally been learning to spell what with writing it so much.
It may seem weird to be so focussed on this one thing what with all the other ways that cryonics can fail, but feasibility is what creates the seriousness barrier. As soon as you think that it stands a really good chance of working, you're over the line with us wacky people, and you're arguing about economics or whether the future wants us or suchlike with real skin in the game.
Earendil wins so hard it makes my ears bleed.
+1 rationality point for reading comments without checking the author. -1 social point for the faux pas.
Is it such an outlandish scenario that given adequate and safe technology cryonics patients will be revived because of humanitarian and moral concerns? I see no reason why we'd switch to a burden-asset evaluation scheme of human beings when we have moved beyond that a long time ago (or more likely we never really adhered purely to it). As of now, there are rather few slaves around and we mostly refrain from killing retarded infants.
Wait, I'm sorry, was this supposed to be a complete list?
This just breaks my heart, because I can understand the fear. I wouldn't want to have children if I thought they'd be taken away from me. But if I already had them, I would want them alive first and foremost. Even if that meant they'd be taken away. Living far away > dying in my arms.
Can we please focus on one argument against cryonics at a time? Isn't this shifting to a new counterargument whenever an old one is addressed just logical rudeness?
If you don't dispute anything I actually say about technical feasibility, please take this discussion elsewhere.
EDIT: Downvotes are useful information, but comments explaining them are even better - thanks!
Also interestingly, there appear to be no published technical articles that claim that it will.
Last week, I searched for articles on how mammalian cryopreservation is done. I found nothing. Not a single journal article on any of the techniques Alcor uses. There are many articles on cryopreserving sperm, and embryos; there are studies on attempting to preserve other types of tissue samples. But I could not find a single article on methods to attempt to cryopreserve adult mammals. Not even in the journal Cryobiology, which is entirely about cryopreservation.
Go to the current issue of Cryobiology and look at the article titles to see what actually is being done in the field. Also notice that the author names are almost all Asian and (non-English/French/German) European. Cryonics for humans is most popular in nations that don't publish on cryonics. (Don't know if it's popular in the Nordic countries.)
That's forbidden by the Society for Cryobiology by-laws.
Cryonics is hard to argue against as it partially involves magic (in the sufficiently advanced technology sense) and it involves something we don't fully understand, how information is stored in the brain. So the lack of technical criticism might be a rare instance of people shutting up about things they don't understand.
Epistemological conclusions shouldn't be based on fear of being scammed. Alcor's motivation should be taken into account Bayesianically, but argument screens off motivation (limited of course by dependence on unchecked facts).
From the Alcor FAQ: "Is cryonics guaranteed to work? No."
Alcor and CI are non-profits.
I recently found this article, that attempts to survey the arguments against cryonics. It only finds two arguments that don't contain any obvious flaws:
Memory and identity are encoded in such a fragile and delicate manner that cerebral ischemia, ice formation or cryoprotectant toxicity irreversibly destroy it.
The cell repair technologies that are required for cryonics are not technically feasible.
This is an implicit appeal to an intuition about a missing dataset. So let me repeat my plea to make this dataset formal! Collect disputes from the past and dig for similar data on them - how many tech arguments by who in their favor, how many against, and so on. And especially - who was eventually right?
The paragraph on climate change seems a little out of place. You must be aware that some of your readership will feel it undermines your case so its inclusion seems almost intended to pull in an unrelated debate into the discussion.
I'm not sure whether or not Melody Maxim should count. She isn't anti-cryonics, but is thoroughly disgusted with the cryonics organizations that exist today- which seems strongly relevant for anyone deciding whether or not to sign up, but not for anyone interested in theoretical probabilities.
The general problem of deciding what to make of theses cases was discussed in the Overcoming Bias post What Evidence in Silence or Confusion?
this is what tipped the scales heavily in favor of cryonics for me. the skeptics make ridiculous claims, and the people who know about the current state of biological research seem genuinely optimistic about it. that's good enough for me considering the low cost and potentially very very high utility payoff.
Your link seems to be broken, but I assume you meant to link this post?
I'm not worried about the technical aspects, I believe it is just a matter of time especially considering the singularity.
What worries me more are economic reasons: will our civilization be stable long enough until we reach the singularity? What about resource shortage, peak oil, global warming, wars? Eventually the cost of cryopreservation will be too high to maintain and cryonics corporations will go bankrupt. The weakpoint is the assumption that the US$ 80,000 will be enough to keep you freezed over the next decades. Conjunction fallacy anyone? Still I... (read more)
I added the sub-debates suggested by Earendil, pdf23ds, and ciphergoth, giving us a total of 7 sub-debates for the cryonics debate:
I found this article in which John Bischof speaks out against cryonics, so I mailed him, and he very politely replied almost immediately to say that cryobiologists consider cryonics a "faith based approach". Sadly he provided no more detail; I've mailed again asking him to write on the subject at greater length.
Update: he replied to my reply. I have also had mail from Ralph Merkle! Will make a new post on my blog with details later.
The New Yorker recently had an article titled The Iceman. Judging from the abstract, it's anti- and not very high quality (excerpt: "The consensus appears to be that when you try to defrost a frozen corpse you get mush", a type of argument covered in your post.)
The Onion on cryonics for college grads.
It seems to me that my death is most likely to come from one of 2 scenarios:
1) I become fatally ill with some disease (e.g. cancer) and, after a period of time, succumb to it.
2) I die suddenly as a result of great physical trauma (e.g. car accident)
Obviously other scenarios are possible, but I think these are the most likely. In case 1 I have plenty of time to sign up for cryonics (and could possibly pay for it with a "settlement" of some sort on my life insurance). In case 2, my body and brain suffer massive physical damage, and the cryonics co... (read more)
Life insurance will become more expensive after you are diagnosed with a terminal illness.
I don't know whether this is on topic since it is not a technical argument, but it is from my field of expertise which is economics. From the CI Faq: "Cryonics is practiced because of a belief that the damage caused by current cryopreservation can someday be repaired."
Now from the preceding paragraphs I get the feeling that science proceeds in the way of developing better preservation techniques that reduce the potential damage. So damage repairing technologies would have to be developed separately. In order for those technologies to be developed... (read more)
Just two minutes ago, a very good anti-cryonics argument appeared to me. This is not my opinion, just my solution to an intellectual puzzle. Note that it is not directly relevant to the original post: I will not claim that the technology does not work. I will claim that it is not useful for me.
Let us first assume that I don't care too much about my future self, in the simple sense that I don't exercise, I eat unhealthy food, etc. Most of us are like that, and this is not irrational behavior: We simply heavily discount the well-being of our future selves, e... (read more)
Er, should this be "cryonics pioneer"?
EDIT: Huh, apparently he's both! Never mind...
Is anyone aware of any article discussing scalability issues?
I agree that from an individual standpoint it is rational to sign up for cryonics but is it really a good idea for mankind in general to massively sign up for cryonics? Would it not create an awful drag on the economy that would delay or maybe even prevent mankind to acquire the technology necessary for reviving the "dead"?
From what I read on the business model of Alcor and CI, the costs of sustaining cryonisation are paid by the dividends/interests of a small capital constituted throug... (read more)
I've written a short followup blog entry detailing the latest in my ongoing search.
I'm an AGW believer (is that the right term), but I'm skeptical whether there's more money for the pro or anti side. Steve McIntyre is retired and gets by on tips (though admittedly he has not outright denied AGW), how many grants have the RealClimate bloggers gotten? At any rate, I think it's a poor form of argumentation to suggest some side of a dispute is just crap inflated with money while overlooking the substantial amounts on the opposite side.
My critique of cryonics: other things are more important, and more worthy of my money, than preserving my own life.
I have three buckets of spending:
To note another contrast, the cost of a single full body preservation at Alcor, plus membership dues, appears to be close to the SIAI yearly budget.
I'm a long way from being an expert neuroscientist, but as far as I can tell the mechanism under which neural change happens essentially involves a few physical changes:
1) Myelination - the Myelin coating over the Axon of a neuron grows, making the Axon conduct it's signal more powerfully and quickly
2) Change in number and distribution of neurotransmitter receptors in the dendrites of the neuron. Obviously the more of them you have, the more likely the neuron is to fire in the presence of the transmitter which fits that receptor.
3) Change in the number and... (read more)
"Pseudoscience" isn't the only possible criticism of cryonics. One could believe that it may be scientifically possible in theory, still without thinking that it's a good idea to sign up for cryonics in the present day. (Basically, by coming up with something like a Drake equation for the chance of it working out positively for a current-day human, and then estimating the probability of the terms to be very low.)
You're right, that most of the popular criticism of cryonics is mere non-technical mocking. Still, there's a place for reasoned objections as well.
Betting on technology that doesn't currently exist is never a sure thing. But cryonics is a good deal even if the probability of revival is low.
Thanks again! I'd still prefer if this sentence were modified so that it doesn't appear to be your thesis on first reading:
You could bracket it in a "skeptics claim X" the way a (good) journalist would, perhaps...
I agree that the link doesn't seem to be working. But I would very interested to learn more. I haven't been all that skeptical of cryonics until now. Logically it seems like if there is a way to preserve the information in your brain, then one day somebody will figure out how to extract it. I guess that's a bit like running an engine on sand. After all, sand in theory contains a great deal of energy in the form of nuclear bonds.
BTW I've studied the issue carefully and probably disagree with you about global warming. Probably it's too charged an issue for rational debate in this forum, but I did lay out my case here:
Your "read more" link doesn't work.
The current Wikipedia article on cryonics states flatly that it is pseudoscience. The citation is: https://www.chicagotribune.com/news/ct-xpm-2002-09-29-0209290429-story.html which again recites the freezing argument, and says that critics include "nearly all mainstream scientists", without really saying who.
I was unconvinced. But attempts to introduce some balance were quickly reverted and got the article locked. I don't have the Wikipedia editing experience to attempt to win an edit war, but if it's still the case that... (read more)
Here is another idea that might be argued to be anti-cryonics. Should we clone Neanderthals?... (read more)
There were some fantastic links here. Thankyou!
Does anyone here know what the break-down is among cryonics advocates between believing that A) in the future cryopreserved patients will be physically rejuvinated in their bodies and B) in the future cryopreserved patients will be brain-scanned and uploaded?
I think there is a reasonable probability of effective cryopreservation and rejuvination of a mammal (at least a mouse) in the next 25 years, but I think our ability to 'rejuvinate' will be largely dependent on the specific cryoincs technologies develop... (read more)
I've added most of your sources to the TakeOnIt wiki debate:
"Is cryonics worthwhile?"
The cryonics debate now has four sub debates:
Am I missing any major sub-debate?
I really appreciate this post. I am in the cryonics process, so it is nice to read an evaluation of the prospects. Even if I have made my decision for now, I could always cancel my life insurance.
The difference between cryonics and, for example, global warming denialism is that the former makes a claim like "it is probably a good thing to do X", while the latter makes a claim like "X is/is not true". These are completely different things!
Perhaps it is better to compare it to the anti vaccine movement. They do make a claim of the form "X is good/bad for you". Now the difference becomes about evidence. For cryonics there is little evidence either way: it has never worked, and it has never not-worked. In such a case there... (read more)
Your definition of evidence is too narrow.
I'd just like to note that Quackwatch is more like a guardian of medical orthodoxy than a place of truthful investigation and has an unflattering reputation among life extension enthusiasts. It provides good conclusions in regard to blatantly non-medicine therapies like faith healing or homepathy but tends to fail when a careful evaluation of evidence is required, for example in the case of diet or supplements.
I posted an argument here: http://lesswrong.com/lw/1mc/normal_cryonics/1i92
I didn't see a major criticism. There were some interesting responses and questions, like what constitutes a 5% increase in quality of life (I don't know; it's a crude metric), but my point stands. You're better off spending your money on marginal increases in quality of life with high probabilities of success than on cryonics.
“Quantum chemistry” a new window into lives of molecules
I suppose the question is how fragile memory really is and if there are any quantum effects involved?... (read more)