One of the most predictable features of public debates about cryonics is that those arguing in favor of cryonics are held to more rigorous standards than those seeking conventional medical treatment. Advocates of cryonics do not just have to prove that cryonics will work, they are also supposed to solve problems like overpopulation and the presumed boredom arising from expended lifespans. To some, people who make cryonics arrangements have an inflated perception of their own importance and should just forgo such selfish attempts to extend their lives. The default position seems to be that people should not exist and that life needs justification. Could you imagine such antinatalist rhetoric being employed when a person seeks conventional medical treatment to extend their life? We can’t, and such responses are quite indicative of the fact that people are not interested in serious evaluation of the cryonics argument.

The most striking case of cryonics being held to higher standards than conventional medicine concerns the requirement that “cryonics” needs to “work.” Even people who have made cryonics arrangements routinely say something like, “I estimate the probability of cryonics working as 5% but life insurance premiums are low and I have nothing to lose if it does not work.” To see how strange such a statement is, let’s look at these two terms, “cryonics” and “working.”

Cryonics is an experimental medical procedure to stabilize critically ill patients at low temperature to benefit from future advances in medicine. Such a definition can include a wide variety of cases, ranging from ice-free cryopreservation (vitrification) as an elective medical procedure in a hospital to the freezing of a person who is found days after circulatory arrest. Considering the enormous variability under which people can be cryopreserved, to claim that “cryonics” will not work without specifying under what conditions a cryopreservation is performed is akin to saying that “emergency medicine” or “chemotherapy” does not work — an absurd claim.

Usually when people argue that cryonics does not work they refer to the mistaken view that cryopreservation that is not initiated within hours, or even within minutes, after death does not make sense because the brain has “died” at that point. Such a view completely ignores the fundamental cryonics argument that lack of function of the brain does not imply that the neuroanatomical basis of identity is irreversibly destroyed.

But let us accept this position the sake of the argument. What such a critic is basically saying is that cryonics cannot work because cryonics patients are cryopreserved under conditions that do not allow it to work. To see how strange such a position is, imagine a country where law would prohibit CPR until 15 minutes of death. Would anyone be impressed if someone would argue that CPR does not work because patients suffer irreversible brain damage after 15 minutes of circulatory arrest? Of course not. We would instead insist that such obstacles should be removed so that these life-saving technologies can be employed as soon as needed. Clearly, whatever the merits of cryonics are, it is not reasonable to conflate the conditions under which cryonics is often conducted with the idea of cryonics as such.

Now let’s look at the second term. What does it mean for cryonics to “work?” Naturally, we would like a medical procedure to cure the disease and restore the patient to the condition than he was in prior to the disease. In real life this often happens, especially in the case of minor infections and minor insults. But there are also many cases where (heroic) medical interventions are aimed at keeping the patient alive without expecting a full recovery without side effects. This is often the case in acute cardio-respiratory arrest and stroke. Would we prefer a complete recovery for such patients? Of course. But would we say that interventions that aim to save a patient’s life did not work if we fail to meet such an ideal – say, a permanent loss of movement in one arm or reduced memory function? No, our first concern would be with the patient’s survival and his perception of the quality of his “new” life.

In the case of cryonics things are not much different. We hope that advanced cell repair technologies will be successful in completely restoring the patient to good health in a rejuvenated state. For some patients complete inference of the original structure of the brain might not be possible, but advanced neural archeology and neurogenomics may restore a significant degree of the original person. We do not heap scorn on such scenarios in today’s medicine and there is no reason to hold cryonics to higher standards, especially if one also advocates the very restrictions that are responsible for such less than perfect outcomes. In fact, there is no reason to be scathing about any credible attempts to save or prolong a life, even if the attempt will not necessarily succeed. Such a perspective is a given in conventional medicine or rescue operations.

One objection to this position is to argue that cryonics cannot work even under the most favorable conditions. Such an argument would basically entail that if a critically ill patient is stabilized without ischemic delays, without ice formation, and without fracturing, it should be categorically ruled out that technologies will ever be developed to repair the original disease of the patient and any form of injury that occurs during the cryopreservation process itself. I personally would consider such a position extremely dogmatic (would anyone argue such a position of long-term technological stasis if the cryonics context were dropped?) but it raises a fundamental question about the burden of proof. Should it rest with the person who aims to prolong life or should it rest with the person who aims to prohibit such attempts? Asking the question is answering it.