Should I Actually Be Working on Cryonics Rather than Rejuvenation?

The small, long-standing cryonics community and industry is focused on saving lives by offering the possibility of low-temperature storage at death, using cryoprotectants to induce a state of vitrification rather than straight freezing, a shot at preserving the structure and data of the mind for a future society capable of revival from this state. This has been an ongoing project for quite some time now, since the 1960s or so, albeit with a small budget and few research programs.

I was recently in New York to attend the 50th anniversary gathering for the Alcor Life Extension Foundation, among the oldest of cryonics organizations. It was an occasion also marking the launch of a new book by Robert Freitas, a specialist in molecular nanotechnology and nanomedicine. The book, Cryostasis Revival, is essentially a 700 page scientific paper that outlines, in detail, what we know of the research and development that would be required to revive a vitrified individual. This starts as a matter of neuroscience, based our knowledge of the brain and its tissues and function, but encompasses a great deal more as well.

People interested in progress in cryonics tend to be interested in progress towards the development of rejuvenation therapies, though there is too little overlap in the other direction. Both were once more fringe than they are now, but work on rejuvenation has expanded and found far more support than is the case for cryonics. There is an old debate, often held between those with a foot in both camps: given that most of us in the later half of life expect the likely pace of progress in rejuvenation therapies to result in a sizeable improvement in old age, but not prevent us from dying from the effects of aging, why are we not fully focused instead on enabling cryonics to become a robust, large, dynamic industry? Isn't the primary object to avoid death, to avoid ceasing to exist? Why not then work on the better solution to that specific goal, rather than a path that can only improve health and thereby longevity in the time we have left?

I was asked this again at the Alcor event by Emil Kendziorra, co-founder of Tomorrow Biostasis, a comparatively new European cryonics venture that may well be pushing some of the older organizations to modernize more than they would otherwise have done, in his role as provocateur. He makes a habit of this, it is a part of his advocacy for the cause.

While I can't talk to the decisions of others, I can shed some light on why I am presently working on rejuvenation, and only plan to focus more of my time on cryonics later in life. Pre-pandemic, I said - to Emil Kendziorra, even - that ten years from now I would be spending more time on cryonics. It may still be ten years at this point post-pandemic, if early access to reprogramming or a combination of other plausible technologies pans out over the next five years and proves influential on health. My timing to switch to work on cryonics is in one sense driven by my projected health trajectory. At what point in the future do I predict that I only have 20 years left before there is a real risk of serious, debilitating age-related disease that drastically limits my ability to contribute? At that point I should put a great deal more effort into making those 20 years a productive time for the cryonics industry.

In the more general sense, considering health and other factors, I will put more work into cryonics when the balance shifts to the point at which improvement in the state of cryonics will be more of a benefit to me than improvements in the state of rejuvenation. "Balance" is a loose word. Guesstimation and gut feel goes into (a) what I think can be achieved for many people over the next few decades via improvements in rejuvenation therapies, (b) what I think can be achieved for myself 20-30 years from now in rejuvenation by helping now, (c) what I can do for the cryonics industry now versus later, and (d) the likelihood that my present efforts in the biotech sector will produce significant personal capital to devote to cryonics research, development, and industry growth.

That last point is an important one. Improvement in the practical implementation of low-temperature cryopreservation proceeds at a very slow pace, with minimal funding. This is a consequence of it being a small field. Yet we can argue quite strongly that the lack of demonstrated capabilities, such as, let us say, reversible vitrification of organs used in the tissue engineering and organ donation fields, is the biggest impediment to convincing the world that cryonics is real. Many people feel that cryonics won't become even a minority concern in a meaningful way until the first person is brought back successfully - but that is a long way in the future, and so we must find incremental steps along the way that will help make a convincing argument to laypeople that this is possible in principle.

At this point, it would probably cost $10 million to $20 million to push reversible vitrification of organs past the point at which more funding will arise organically and industry will inevitably form. Either philanthropy focused on academic-style programs or a deep-pocketed venture backed company might achieve the same result. But money doesn't grow on trees, and so far even the more visionary philanthropists have committed only a fraction of this amount to this sort of cryonics research. Turning up to put my shoulder to the wheel with the intent to find this funding is one thing. Turning up with those funds in hand is quite another. The odds of either path working out, and when they will work out, are worth considering when running the calculus of when to become more involved.

In any case, I am sympathetic to the argument that one should be working to speed up the growth and development of a future cryonics industry. One day I will do more than talking about it. Just not today.


This is a fascinating article! I thank all the good people working on rejuvenation AND cryo preservation, but I have a couple of other back-up plans worth considering:
1) Have lots of kids with the finest women you can talk into it. They will be better than an old you in a couple decades.
2) Write down and promulgate your best ideas (you've got the gist of a GREAT BOOK already at this site!). One can argue that the spread to others of the essence of your conscience can be more important, meaningful, and powerful than you hanging around keeping a light lit unto itself.
3) Start thinking and even praying about the possibility of a divine existence beyond your physical embodiment. David Icke has put together several videos on What is Death, The Afterlife & Consciousness, as well as interviews about his recent experiences that are pretty compelling.

Posted by: Thomas Mark Schaefer at March 3rd, 2022 2:48 PM

Hi @Reason. Have you told us your chronological age? So that we can fit ourselves into this decision process. No that I'm feeling great about running headlong into cryonics. Just curious, but if you don't want to share that, well then, obviously you don't need to.

Posted by: Matt at March 3rd, 2022 4:46 PM

@Thomas Mark Shaefer

Instead of a divine existence, how about just reasoning through what likely happens after death.

Here is my chain of logic:

1. you die. You no longer exist. You cannot sense not being alive.
2. This is the same situation "you" were in before you were "you".
3. Another creature that has a mind capable of consciousness is born, it creates a new "me".
4. Welcome to "your" new life.
5. Life is great!
6. You die, goto #1

Now of course it's unlikely you'll be a human again. But you also don't need to worry about being a bacteria or a tree because while those are living they don't have a consciousness. Therefore "you" cannot be a tree or a bacteria because "you" is a manifestation of a mind.

Hope this makes you feel more comfortable. It does for me.

Posted by: Matt at March 3rd, 2022 4:59 PM

What is the largest creature that has been successfully frozen and revived?

Posted by: Jimofoz at March 3rd, 2022 5:17 PM

I turned 48 a few days ago and I'm finally planning to sign up for cryonics before I turn 50 (I don't have the money yet, though). Rejuvenation biotechnology is gaining traction but still it advances too slowly, particularly in fields like neurodegeneration and stem cell therapies.

Posted by: Antonio at March 4th, 2022 3:54 AM

Its provocation seeing how much resources are wasting in Ukraine war. If humanity could go beyond tribalism we will someday enter the star age.

Posted by: ciclo at March 5th, 2022 7:26 AM

Definitely rooting for you and the whole rejuvenation sector :) I'd much rather extend my maximum life span without needing to ever be cryopreserved.
Unfortunately, I think it will be much harder to translate the extension of health span (which will be achievable and already is) into the extension of life span and that the optimism in the whole field isn't really warranted. Apart from the needed calculated optimism, to raise funding, etc.
Until there's a more fundamental change, I think it's prudent to work on cryopreservation and make the argument that more people should.
Especially, since there is a crazy amount of work to be done. @Anybody: happy to discuss in more detail, feel free to reach out.

PS: Health span extension is a very worthwhile goal in itself in my mind. It just won't lead to (much) longer maximum life span.

Posted by: Emil Kendziorra at March 5th, 2022 4:03 PM

Good post. I agree w/ Reason's general idea of weighting rejuvenation more than cryo at this point. A few points come to mind.
-Even modest rejuvenation could be a bridge to cryonics.
-Being frozen is not optimal, since you no longer have much control like a "live" person would.
-I've always wondered if a cryo technique will be developed that works on the old but not the very old. IE A 70 yo might survive the freeze-thaw process but a more fragile 90 yo might not.

Posted by: K at March 5th, 2022 5:02 PM

I take it Reason is losing faith that something worthwhile will happen in the anti aging field in the next 20 years, which is exactly what I feel. Even 20 years would be too late for me, I think by then I'll be so old, frail and unmotivated to still care...

Posted by: mcmp at March 5th, 2022 6:09 PM

It had been 20 years since started ( originally it was

Reason, if you are planning to focus your time and attention more on cryonics, then please find a volunteer or hire someone to continue working on rejuvenation and to continue this website:

It is obvious that both are needed: cryonics and rejuvenation.
If cryonics is successful and you are frozen and many years in the future defrosted, revived and your mental faculties normal, you still would want to be rejuvenated ( you would not want
to continue living as an old person) And while you were frozen , there would be other humans working on rejuvenation and finding a cure. … and continuing managing this website.

" isn't the primary objective to avoid death, to avoid ceasing to exist" - indeed it is. Avoid death - continue living for ever young and healthy. It is against your faith to sacrifice your life, to die for your country. Physical immortality is the one cause you can not die for.

My personal opinion is : I don't fear being dead, - being nonexistent [ although I may fear the dying process - it can be painful and dreadful. I dread of becoming dead, but not being dead - I will not have consciousness or pain or fear.

5 billion years in the past " i " did not exist and it was neither good or bad - it was neutral.
If 5 billion years in the future " i " will not exist - it will be neither good or bad - it will be neutral.

So my attitude towards my own nonexistence is neither joy nor sorrow . It is equanimity.

Posted by: nicholas d. at March 6th, 2022 2:02 PM

I hear many people here say they don't fear nonexistence, but I think often the reality of the situation is different. When actually faced with death (from say a disease), even if they are suffering, the vast majority of people in the world still do everything they can to live (And most of those people believe in an afterlife, unlike most people reading this blog).

Yes, the fact that you at one time didn't exist is not too troubling to many people, but existing and then losing that existence is different. Of course, very long term, rejuvenation should make the issue moot since it will eventually lead to (nearly) perpetual health and youth.

Posted by: K at March 6th, 2022 3:11 PM
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