One argument I can think of to sign up for cryonics sooner rather than later is to create social proof for your extended family. The idea of evading death by freezing yourself and awaiting future technology for a cure might be too outlandish for older people to seriously consider, and leading by example might ease that process. And while you perhaps can afford to wait for better procedures or evidence about efficacy of cryonics, your parents/grandparents probably can't.
There is a decent chance that we are already at the freezing part of 2. For instance, a defrosted vitrified rabbit brain apparently appeared to be in good order, though I assume we don’t know how to reattach brains to rabbits, alas.
The reference was aldehyde-stabilized cryopreservation, which is quite a bit different than a typical vitrification procedure. In particular, you can't just rewarm the tissue and expect it to function at all. When aldehyde-stabilized cryopreservation won the Large Mammal BPF Prize in 2018, the authors of the announcement had this to say about the technique,
It is important to understand that the researchers did not actually revive a pig or pig brain. The first step in the ASC procedure is to perfuse the brain’s vascular system with the toxic fixative glutaraldehyde, thereby instantly halting metabolic processes by covalently crosslinking the brain’s proteins in place, and leading to death by contemporary standards (but not necessarily information-theoretic standards). Glutaraldehyde is sometimes used as an embalming fluid, but is more commonly used by neuroscientists to prepare brain tissue for the highest resolution electron microscopic and immunofluorescent examination. It should be obvious that such irreversible crosslinking results in a very, very dead brain making future revival of biological function impossible. So, it is reasonable to ask: “What is the point of a procedure that can preserve the nanoscale structure of a person’s brain when biological revival is impossible?” The answer lies in the possibility of future non-biological revival.
A growing number of scientists and technologists believe that future technology may be capable of scanning a preserved brain’s connectome and using it as the basis for constructing a whole brain emulation, thereby uploading that person’s mind into a computer controlling a robotic, virtual, or synthetic body. The Brain Preservation Prize challenged the scientific community to develop a ‘bridge’ to that future mind uploading technology. The similarity to cryonics is obvious, but in this case the possibility of biological revival was dismissed as currently not feasible. Focus was instead directed toward provably preserving the information content of the brain as encoded within the connectome. Quoting from a recent video presentation by BPF President Kenneth Hayworth: “Aldehyde-Stabilized Cryopreservation is cryonics for uploaders.”
https://forum.effectivealtruism.org/posts/vqaeCxRS9tc9PoWMq/why-are-some-eas-into-cryonics
Helpful links on the topic.
The waitbutwhy post also has very helpful links.
People around me often sign up for cryonics, and say that it is very important. My guess is that this argument for it, heavily inspired by Waitbutwhy’s much longer piece, as well as years of talking to people around me and reading their blogs, is correct:
1. One day people will probably live much longer than they do now.
Probably we will work out how to beat the diseases of aging, as we have many of the infectious diseases. Eventually dying at age 90 of heart disease will seem as much of a needless tragedy as dying of an infection at age 45 does to us now.
2. One day we will probably be able to ‘freeze’ and usefully thaw organs like brains using vitrification.
We can already do this with other organs. For instance a rabbit kidney can apparently already be vitrified then warmed up and put back in a rabbit and work.
3. People can start to successfully evade the diseases of aging as soon as science reaches the freezing part of 2, even if it hasn’t got to the thawing part or to 1 yet.
Because once you are vitrified, you can wait quite a long time for further developments.
There is a decent chance that we are already at the freezing part of 2. For instance, a defrosted vitrified rabbit brain apparently appeared to be in good order, though I assume we don’t know how to reattach brains to rabbits, alas.
The chance that we are there on the freezing is high enough that people dying soon (by our current standards of irrevivability) should generally be vitrified instead of burned or buried, if the chance to survive longer is worth the price to them.
You can sign up for something like this at the cost of a not-super-expensive life insurance policy, though I think the more promising techniques at the moment aren’t available yet to purchase.
I haven’t actually signed up for this, but I might, and if I thought there was a higher chance of me dying sooner, I would get around to figuring it out more urgently. So I thought I’d point it out to others older than me, who might want to think about it more promptly.
I found Waitbutwhy’s essay on these topics pretty good.