I wrote a blog post arguing that people sign up for cryo more for peace of mind than for immortality. This suggests that cryo organizations should market towards the former desire than the latter (you can think of it as marketing to near mode rather than far mode, in Hansonian terms).

Perhaps we've been selling cryonics wrong. I'm signed up and feel like the reason I should have for signing up is that cryonics buys me a small, but non-zero chance at living forever. However, for years this should didn't actually result in me signing up. Recently, though, after being made aware of this dissonance between my words and actions, I finally signed up. I'm now very glad that I did. But it's not because I now have a shot at everlasting life.



For those signed up already, does peace-of-mind resonate as a benefit of your membership?

If you are not a cryonics member, what would make you decide that it is a good idea?

New Comment
32 comments, sorted by Click to highlight new comments since:

I don't want Cryonics companies to focus on selling fantasies, I want them to focus on making the technology work.

The value of giving people 'peace of mind' is low, and there are already tons of religions out there that do that. The value of actually letting people live again after death would be immense.

Focus on reality.


Until and unless they do make the technology work, they are selling fantasy.

I... I don't actually understand why this comment got so many downvotes—and I'm 100% for cryonics. In fact, I agree with the above comment.

Is this a toxic case of downvoting?

Definitely. Before such technology comes into existence, cryonic preservation for future Resurrection is fantasy.

Cryonics will definitely fail if the peace-of-mind cryonicists dominate it instead of the serious adults who want to survive.

You can see most cryonicists' fundamental lack of seriousness from the fact that they talk a good game about how much they believe in scientific, technological and medical progress. So what happens when you try to draw their attention to the many correctible shortcomings in the real, existing practice of cryonics? They usually shrug those off as if these problems don't matter.

Uh, hello?

This fundamental lack of an evidence- and reality-orientation in many cryonicists goes a long way towards explaining why mainstream people don't find the cryonics idea credible, much less its haphazard implementation. I just have no patience these days with cryonicists who invoke Eric Drexler's discredited fantasies from the 1980's, or who make fallacious comparisons between cryonicists and the Wright brothers. Cryonics falls into the overlap between neuroscience and cryobiology, and progress in it will have to come from the application of those real sciences.


The way that cryonics was explained to me that made reasonable sense:

On a scale of spreading ashes far and wide; to cooling down your atoms so they are not moving enough. How preserved is thing X. Where ashes are pretty much 0 = not preserved, and cryogenic freezing is 0.99 and more if cooler.

after preserving there is a much higher chance of recreating the preserved entity than after ash spreading. if you believe the chance that medical and recovery technology will be able to revive a preserved entity to be non-zero; you should partake in cryonics for a future N. Where N may be as long as it takes to wait till your revival.

The major questions:

  • where does consciousness come from; and can we give it to back an entity that died? (while I don't doubt we can answer that eventually; the answer might come in the form of "yes but its far too difficult and expensive")
  • if for example we 3d print a brain that entirely matches a cryonically preserved entity; then link it up to a body, will it be possible to impart consciousness to it?
  • is it actually possible to measure the state of a preserved entity without destroying it?
  • can we recreate a preserved entity from the knowledge of where the atoms in its brain were?
  • will it ever be possible to do so? (as you get closer and closer to perfect recreation; it probably gets harder and harder to do)

I am not enrolled in cryonics, but have nothing against people taking the bet.


I absolutely agree with you that there are correctible shortcomings in today's cryonics practice; I also agree that we'll need a whole lot of neuroscience and cryobio to make further progress.

The Mikula paper linked in the article shows one possible avenue to verifiable cryo. The technology exists today: getting the engineering right so that it can be rolled out to paying customers seems to be the difficulty.

If I remember right the estimation of successful revival via cryonics by LW people who are signed up for cryonics is <0.2. I don't see how that is supposed to produce peace of mind.

Once one's done all one reasonably can about a problem, one can stop worrying about it, even if the problem's still there. No point wringing one's hands about what one can't change.

Granted, I doubt most people's minds actually operate on that principle. Futilely dwelling on a problem seems to be quite common.

There are a lot of choices for healthier living that most people don't take. Not thinking about your health because you are signed up for cryonics seems to be a bad strategy,


Granted, I doubt most people's minds actually operate on that principle.

Mine does some of the time, and when it doesn't, I try to force it to do so.

It could well be, that their estimation of a successful revival is significantly higher than they are letting on.

I don't know what you mean with "letting on". The census asked very directly for a probability value of successful revival.

I don't know what you mean with "letting on". The census asked very directly for a probability value of successful revival.>

I mean that their actual revival estimate may be a lot higher than they are willing to acknowledge, which would explain the peace of mind.


I've always been afraid of dying: every lurch of a plane in turbulence gets my palms sweaty; every nearly-avoided mishap I encounter while driving makes me vow to drive even less than I currently do. I won't even consider going on a cruise until I learn to swim.

Cryonics or not, if you die in a plane crash, car crash or ship sinking you will not come back.

This is almost certainly true for most plane crashes or ship sinkings.

However, it is not necessarily true of a car crash, and this is a common misconception. In most motor vehicle accidents, individuals do not die instantaneously, and it can take many hours or even days for death to be pronounced.

This is why, for example, people are more likely to die if their car crashes in a rural area than an urban one, where they have less access to hospitals.

If you have standby services in place, and they are able to get to the hospital in a reasonable interval, then this would not affect your preservation that much, in the absence of blunt trauma to the head or cerebral hemorrhage.

As an example of this, consider one of the most famous car crashes: Princess Diana, who died three and a half hours after a particularly high-impact car crash.

So, if you accept the premise of cryonics in the average case (obviously a big if), then dying in a car crash is not necessarily going to stop the procedure from being successful.


However, it is not necessarily true of a car crash, and this is a common misconception. In most motor vehicle accidents, individuals do not die instantaneously, and it can take many hours or even days for death to be pronounced.

I'm not a doctor, but I suppose that in most cases where death is pronounced after days the cause of death is traumatic brian injury, therefore even if cryopreservation can be performed immediately after death is pronounced the brain will be already extensively damaged.
Other cases of death in a car crash probably involve cardiac arrest caused by damage to the heart, lungs, major blood vessels or spine. In these cases I suppose that ischemia occurs within minutes to hours from the trauma, therefore unless there is a cryonics team on standby at every hospital, the brain is going to suffer many hours of ischemic damage before cryopreservation can be performed.

Good point. As somewhat of a nitpick, I've heard that with some types of brain injury (especially those resulting from rotational forces and indirect impacts), a large portion of the total damage may be from secondary effects - my understanding is that this results from a chemical cascade that may only appreciably occur 4-30 hours after the event.

No citations and won't even bother for a hypothetical case - just a bit that I've read here and there. Google keywords are probably "secondary injury", "DAI", and "diffuse axonal injury".

I get the sense that many of the people who have signed up have done it less for the increased survival chances or the sense of comfort, but as a sort of flag waving. It is pretty good signalling that you are opposed to death and part of the ingroup that is opposed to death. Those little medallions are badges of a refusal to submit to the awful thing.

Yes, I get the same impression. In fact, Eliezer basically said that for a long time he didn't sign up because he had better things to spend his money on, but finally he did because he thought that not signing up gave off bad signals to others.

Of course, this means that his present attitude of "if you don't sign up for cryonics you're an idiot and if you don't sign up your children you're wicked" is total hypocrisy.


Whoa! If that's true then Alcor should offer necklaces (different looking from thereal ones) that say something like "I stand against death!". That way people can signal allegiance without having to go through all the cryo paperworks.

That kind of misses the point. There are lots of neckslaces that have peace sign on them, but they're not at all a good signal of pacifism, or nuclear disarmament (what the peace sign originally stood for). Think of how many people where a ying yang because it looks cool instead of to convey an affinity, much less a dedication to, for Taoist ideals.

It is because the necklace is expensive and represents an actual (if small) step towards destroying the awful-thing, that it is good signalling.

Part of this is because the more expensive the thing and the more marginal the benefit, the more it shows dedication to the cause. This is basic commitment effects. But there's another thing. Signing up for cryonics doesn't just signal that you don't like death, it signals that you're prepared to do something about it. Complaining is common. Doing something isn't.

Also, I'm not sure why anyone would want alcor (or anyone) to offer such necklaces. Don't we want' people to sign up for cryonics?

You'd have to want to signal very strongly to overcome the inconvenience of doing the paperwork and forking over cold hard cash. Self-signalling seems to be a plausible motivation, but I'm not sure how much benefit you'd get from being able to tell other people about it. Not to mention the opposite pressure that most people have because they have to convince their close family members to respect their wishes.


Signing up didn't bring me peace of mind, except for brief relief at not having the paperwork on my to-do list.

I've heard other cryonicists report feeling something like peace of mind as a result of signing up, but they appear to be a minority.


Someone at dinner used the phrase "when the worms get me" and I immediately reached under my collar to make sure I was wearing my magical anti-death amulet. So glad I'm signed up for Cryonics.

Sounds about right.

I don't understand the distinction being made. The chance of revival and peace of mind aren't separate things: it is the former that causes the latter.

If you are not a cryonics member, what would make you decide that it is a good idea?

I don't think it's a crazy idea, but I'm not signed up. I might reconsider after some leaps and bounds in the technology, like successful short-term freezing and revival of humans. I am not expecting to see that within my expected lifespan.


Would you reconsider if you saw successful revival of a small organism? C. Elegans? A mouse?


C. Elegans can be already cryopreserved and revived, mice can't.

Keep in mind that any success on small organism doesn't necessarily translate to larger organisms due to the square-cube law: the heat capacity of an organism, or its brain, is proportional to its volume, while the speed at which you can cool it for a given temperature difference is proportional to its surface.

If the temperature difference between the inside and the outside is too high, the outer layers freeze/vitrify and contract before the inner layers, causing cracking. If the cooling speed is too low, you get lots of ischemic damage and large ice crystal formation.
Ice crystal formation can be reduced or inhibited using cryoprotectants, but the slower the cooling speed the higher the concentration of cryoprotectants is needed, and cryoprotectants are toxic at certain concentrations (used by cryonics companies), causing protein denaturation an cell membrane distortion.
The speed at which you can perfuse cryoprotectants is also limited by a square-cube law. In the protocol used by cryonics companies, cryoprotectants perfusion takes many hours.

A mouse brain is about 3,000 times smaller than a human brain by mass, therefore even if someone managed to cryopreserve and revive a mouse it wouldn't imply that the method is scalable to humans.

Those would be steps on the way, of course. I thought C. elegans had been done already, and anyway, there are any number of tinier creatures that can go into decades-long stasis naturally. A mouse is where it begins to get interesting, but it is future me who would be reconsidering, and I can't speak for him.

I have a regular life insurance a small portion of which could be used to buy a cryonic burial (there are ways to get an advance on one's life insurance while you are still kicking) should I want one.

I have guesstimated the odds of the eventuality where a preexisting cryo coverage would be better than buying it when actually needed, and they seem very low:

  • any disease or accident resulting in brain damage renders cryo useless
  • any accident resulting in quick death renders cryo useless
  • any situation where end of life is not immediate but expected within a short time frame (e.g. aggressive incurable disease) without affecting mental faculties leave time to make cryonic arrangement through savings or existing insurance if desired.

The only reason I see to buy cryo insurance is more of an altruistic nature: to financially support a cryobank before I need their services so that they can freeze some of those who cannot afford it.

There is also the potential issue of their business model relying on people paying for but not being able to use the coverage, but if they actually do that, I cannot expect them to last long enough to attempt a successful revival.

From the title of the post, I thought it would be about how not signing up gives you certainty. I've read someone who doesn't want to sign up say that dying in a normal way would give their family peace of mind.

In terms of whether it's a benefit, if it does motivate you then it's a good Dark Arts way to stop putting off signing up. However, cryonics companies changing their image to take advantage of it strikes me as a really bad idea for the reasons in Ander's post.