Cryonics: The Issues

(An Overview)

by Ben Best

For an overview of the essential questions of cryonics in Question & Answer form, see my piece Cryonics — Frequently Asked Questions (FAQ). (The FAQ is more comprehensive and up-to-date than this essay.)




As defined in WEBSTER'S NEW UNIVERSAL UNABRIDGED DICTIONARY, cryonics is "the practice of freezing the body of a person who has just died in order to preserve it for possible resuscitation in the future, as when a cure for the disease that caused death has been found." If future molecular-repair technology can repair damage caused by cryopreservation (including freezing-damage), cure all diseases and stop (and reverse) biological aging — then cryonics is the "first aid" which can preserve contemporary humans for future science. A few people look forward to the time when their minds can be uploaded to a computer. In either case, cryonics may be the gateway to a future world of eternal youth and prosperity.

Cryonics is to be distinguished from cryogenics, the physics of low temperature, and cryobiology, the science of low-temperature effects on biological systems. Use of the word "cryogenics" to mean "cryonics" is a quick tip-off that the speaker or writer is ignorant of the subject of cryonics.

As currently practiced, cryonics is a radical approach to saving life. Cryonics is radical in two different ways:
(1) Cryonics cannot be proven to work or proven not to work until some time in the future. Cryonics is dependent on a future technology, and there is no guarantee that the future can create the required technology.
(2) Most people who seek cryonics are not simply wanting a procedure comparable to heroic surgery. Cryonicists are usually people who want a procedure which can transport them to a future technology capable of restoring youth, and extending youthful lifespan hundreds or thousands of years or more.

If the desirability of a life that is hundreds, thousands or millions of years in duration is puzzling to you, you might want to consult my essay Why Life Extension? [Ethics of Cryonics]

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For legal reasons, cryonicists currently only freeze people who have been declared legally dead. Cessation of heartbeat and respiration do not equate with biological death, however. Artificial respiration and CPR have brought many people "back to life". Usually when heartbeat stops most of the cells in the human body are still very much alive. It is now known that brain cells do not die five minutes after circulation stops; instead, brain blood vessels go into spasm and blood thickens. Although tissue cells are still alive, after protracted cessation of circulation any attempt to restore circulation (without preventative measures) causes further tissue cell damage by "reperfusion injury".

Biological death is a process, not an event, and the deterioration of the biological basis of life (cells in tissues and organs) occurs over a period of many hours after cessation of heartbeat. Cryonicists seek to initiate cryopreservation procedures as soon after the legal declaration of death as is possible, to minimize deterioration of cells. Cryonicists refer to those being cryopreserved as "patients" rather than "dead people" — in keeping with the thought that cryopreserved people still have the basis of life within them, but are very medically compromised.

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Although steps can be taken to minimize freezing-damage, such damage cannot be completely eliminated. Nonetheless, damage is distinct from destruction. A structure that is merely damaged can ultimately be repaired. Future science may well be able to cure most disease, repair freezing damage, and stop as well as reverse aging. At liquid nitrogen temperature (-196ºC = -320ºF), biological structures in need of repair can be preserved many millions of years with virtually no change. Most cryonicists expect the necessary molecular repair technology within 50 to 100 years — but are prepared to wait as long as it takes.

The future technology to accomplish the reanimation and rejuvenation of cryonics patients will probably be the outcome of current trends toward microminiaturization. Ultraminiature robots may someday remove cholesterol from arteries. Genetically engineered micro-organisms may be able to repair DNA damage. Nanotechnology (nano=billionth, as in nanometer) will be able to manipulate matter on a molecular or atomic scale. K. Eric Drexler (who MIT granted the world's first Ph.D in Nanotechnology — a field he virtually created), foresees the capacity to produce self-replicating nanomachines which can not only cure diseases and repair freezing damage, but which can manufacture food, skyscrapers or spaceships from dirt. The chapter "A Door to the Future" of Drexler's book ENGINES OF CREATION caused many more people to take cryonics seriously.

Nanotechnology is not simply a pie-in-the-sky dream of the future. It is a scientific reality which is already showing advances. In 1990 IBM researchers spelled their corporate logo by positioning 35 xenon atoms on a nickel surface. Hundreds of nano-scale devices have already been fabricated at the National Nanofabrication Facility at Cornell University.

California Institute of Technology scientists have determined the complete structure of a bacterial flagellar motor, which is a first step toward building similar nanomotors [NATURE; Murphy,GE; 442:1062 (2006)]. Stuart Hameroff at the University of Arizona is using a scanning tunneling microscope to gather information on intracellular coding systems. He wants to construct custom-made, self-replicating white blood cells that could seek-out the neurofibrillary tangles of Alzheimer's Disease, and destroy them with enzymes. (Articles in SCIENCE;317:333-336 (2007) and the September, 2001 issue of SCIENTIFIC AMERICAN give more examples of the possibilities of biomedical engineering with nanotechnology.)

Belief in the ability of future nanotechnology to have absolute control over matter on the molecular level has caused many cryonicists to arrange for only their head to be cryopreserved (which is much less expensive than cryopreserving the whole body). If nanotechnology can be used to construct any material object by putting atoms and molecules together, then repairing freezing damage, reversing aging, and building a new body around a preserved brain will be manageable problems. Although the logic of this idea is hard to argue with, it provokes much shock and consternation in some people. Cryonicists describe the two main categories of cryonics patients as "neuro" (head-only) and "whole body".

Many, if not most cryonicists, are not pleased with the idea of so much reliance on nanotechnology or other future technologies. Instead, they concentrate their efforts on research to achieve full suspended animation through cryopreservation within our lifetimes. To see reports on the results of such research, consult my papers A Summary of the First 21CM Seminars and The Hippocampal Slice Cryopreservation Project. (Research at 21st Century Medicine (21CM) — which contributed enormously to progress in cryonics technology — has been funded almost entirely by The Life Extension Foundation.)

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There are Arctic reptiles such as frogs and salamanders that can survive very low temperatures with a large part of their body water converted to ice. They can do this because their livers manufacture a large amount of glycerol. Glycerol is antifreeze: it reduces ice formation and lowers freezing point. Other arctic insects & reptiles use sugars as antifreeze. Such antifreeze substances are called cryoprotectants.

A cryoprotectant can make water solidify the way glass hardens: with no crystal formation. Freezing-damage to cells is due to the formation of ice-crystals, which grow between cells and crush them — or the creation of toxic hypertonic solutions. Evidence of freezing damage can be seen by freezing and rewarming lettuce or strawberries.

In 1949 it was discovered that glycerol can be used to protect bull sperm against freezing injury. A year later, the same techniques were successfully applied to red blood cells. Since that time large industries have developed around the cryopreservation of bull sperm and human blood for long-term preservation at liquid nitrogen temperature.

In 1959 the substance DiMethyl SulfOxide (DMSO) was demonstrated to be useful as a cryoprotectant. DMSO passes through cell membranes more readily than glycerol, but it can be more toxic at higher temperatures. In 1972, 8-cell mouse embryos were cryopreserved to liquid nitrogen temperature temperature and rewarmed to obtain live mice, thanks to slow cooling and skillful combination of DMSO and glycerol. In 1982 a human pregnancy was first established using an 8-cell human embryo, which had been cryopreserved using similar techniques. "Suspended animation" of human embryos is now commonplace, and there are living children who were once cryopreserved embryos.

Cryoprotectants used in cryonic cryopreservation reduce freezing damage, but do not eliminate it. Progress continues to be made in the reduction of damage, but damage still occurs. The crucial question is: does freezing damage destroy beyond all repair the biological basis of human consciousness and identity? No one can answer this question with certainty until science discovers the physical basis of consciousness and identity in the brain. Cryonicists are hoping that all damage is reparable with nanotechnology and that research on vitrification is eliminating freezing & cracking. [For further discussion of vitrification technology, see my essays Vitrification in Cryonics, Physical Parameters of Cooling in Cryonics and Lessons for Cryonics from Metallurgy and Ceramics.]

Some people worry that the cessation of electrical activity during cryopreservation would mean a loss of personal identity & memory. Although immediate (short-term) memories would probably be lost, there is ample reason to believe that identity & long-term memory is encoded in synapses and in the connections between neurons — which would be cryopreserved. (For more on this and related subjects, see my essay Neurophysiology and Mental Function and my essay An Overview of Neural Networks.)

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In all of human history there has never been a well-documented case of a person living much longer than 120 years. Claims that people have lived to 150 years in the Caucasus mountains of the Republic of Georgia and in the village of Vilcabamba in Ecuador have been disproven. The Georgians of the Caucasus made a practice of adopting the identities of their fathers or grandfathers to avoid military draft. Church and civil records in Vilcabamba establish that the oldest inhabitants are in their 90s, and that the high proportion of elderly people is primarily due to the fact that young people tend to move away.

In the last 2000 years, there has been a trend in Western Civilization toward increasing lifespan. In ancient Rome, the average lifespan was 20, by the year 1900 it was 63 and in 1985 it had reached 75. As recently as 130 years ago, over half the population died of infectious diseases. Cancer and heart disease were invariably fatal prior to 1950. But maximum lifespan has not changed at all since ancient times: Aristotle died at 62 and Plato lived to be 80.

Comparison of species offers evidence that maximum lifespan is the result of genetic programming. The cells of a rodent seem comparable to the cells of a human being, yet a rodent ages and dies by its third year. For humans, the incidence of cancer doubles about every 9 years after age 45. By the age of 85, about 30% of humans have had cancer. By age 3, about 30% of rodents have had cancer. Cancer is due to alterations in DNA — the chemical structure responsible for genetic makeup.

One of the most famous experiments in gerontology was done by Leonard Hayflick. He observed that embryonic cells in tissue culture would divide about 50 times before they ceased dividing. This 50-division limit seems to be a property of the cell nucleus or DNA. If an old nucleus is transplanted to a young cell, the nucleus still divides no more than 50 times. And if a young nucleus is transplanted to an old cell, the nucleus still divides 50 times. The Hayflick Limit of number of cell divisions seems to indicate a maximum human lifespan of between 110 and 120 years. Telomeres, which protect the ends of chromosomes the way plastic caps protect the ends of shoe laces, seem to be responsible for the Hayflick Limit.

But not all cells obey the 50-division limit. Cancer cells and reproductive cells, for example, seem to be immortal — having no limit to the number of times they can divide. Reproductive cells have a powerful capacity for DNA-repair — otherwise species could not have survived millions of years. Cancer cells and reproductive cells have an enzyme (telomerase) that keeps telomeres intact.

There are other mechanisms of aging besides those involving DNA. Our bodies contain highly reactive chemical agents called "free-radicals", which can cause DNA damage and cross-linking. ("Free-radicals" are highly reactive and highly destructive chemical substances that normally appear in small quantities in biological tissues.) Cross-linking makes tissues harden and lose suppleness. The immune system declines in effectiveness with age, becoming not only less capable of attacking bacteria, virus and cancer, but more likely to attack the body's own tissue (as in the auto-immune disease of arthritis). The body may even manufacture a "death hormone" — such as the one that makes salmon rapidly age and die after spawning. Removal of the optic gland from the octopus increases its lifespan by 5 times — suggestive of a "death hormone".

Aging appears to be due to a limited number of factors: (1) genetic programming (2) wear-and-tear on genes by free-radicals and other agents (3) general crosslinking and wear-and-tear of body tissues that is not repaired or (4) accumulation of various kinds of "garbage" from internal and external sources that is not eliminated and "clogs" biological function. Future medicine must therefore be able to (1) stop genetically programmed aging by direct control of gene expression (2) repair damaged genes and reduce access of free radicals to DNA (3) undo cross-linking and repair or replace damaged structures and (4) engineer nanorobots or other means to remove accumulated body garbage. Whatever the mechanisms of aging, it is a biological or biochemical process — and is therefore subject to human intervention, control and reversal. It is not an inevitable restriction on human potentialities — any more than gravity is a natural law preventing humans from building flying machines.

Enzymes, the protein-composed natural chemical catalysts found in all biological cells, are themselves tiny machines that manipulate matter to produce desired molecular re-arrangement. Just as engineers have built race-cars that are faster than cheetahs and airplanes that fly higher than birds, engineers should be able to build nanomachines that will not only be stronger and more stable than enzymes, but able to exert more force with greater precision. Nanocomputers could fit a billion bytes of information in a box the size of a bacterium. Self-replicating nanomachines in a hundred years may well be able to repair any part of a human cell — including DNA.

For more technical information about what science has been learning about the mechanisms of aging, see my essay Mechanisms of Aging

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For many people, the prospect of living in the future means much more than extended lifespan. They are excited by the possibility of space travel and of the transformation of human life. In a world of wealth & advanced technology people will have more time to pursue their dreams and be less constrained by the requirements of work. People may be superhuman with bodies engineered for better sensation, better protection, better thinking, instantaneous communication with any other person or machine and greatly enhanced capabilities for love & sensual pleasure.

(For some speculations about Transhumanist possibilities see the book by Robert Ettinger, the "father of cryonics": Man into Superman)

Some people imagine cryonic reanimation as entering a cold, alien technological world of strangers — without loved-ones or skills for coping. This is especially puzzling insofar as the whole history of technical progress has been characterized by making life better for everyone, including — perhaps especially including — people with physical and mental handicaps. A world with the technology to reanimate a cryopreserved person would probably be filled with superior means of helping people to become adaptive and productive — including high-tech training technologies and technical means of enhancing mental and physical powers. Technologically-enhanced human intelligence may ensure that machines with artificial intelligence will not become the new masters of civilization.

The idea of being in the future without those we love is enough to cause many to think that such a life is not worth living. It would be far better to work to ensure that loved-ones join us in our plans to be cryopreserved & reanimated. Harder to accept, perhaps, is the idea that our capacity to love is not restricted to certain individuals and that the fact that we do love means that we can — that we can find new people to love.

It is very unlikely that we would be reanimated into a dystopian future in which we are handicapped, diseased or disfigured — and surrounded by totalitarian brutes. If the world did degenerate to such a level we likely would not be reanimated. If reanimation technology is employed, those who implement it would be careful not to use it until it can be done in such a way that the reanimated person is in the prime of life & health — in a body far superior to the previous one. A technology with the capacity to reanimate would be a technology in which there is no aging & disease. There would be no rush to reanimate before the proper technology is available. Those reanimated first would be those preserved last (LIFO — Last In, First Out) — preserved with the best technology.

As for being reanimated into a totalitarian world, the progress of civilization has been toward more freedom, more justice & more democracy for more of mankind. This progress is likely to continue and accelerate.

Some people doubt that future generations would have any incentive to reanimate them. The contractual agreement with a cryonics organization and a fund which can pay for maintenance, yet still grow faster than inflation, should be adequate incentive for reanimation. But it is worth observing that a significant percentage of people currently cryopreserved are the parents of cryonicists. Moreover, cryonicists living in the same geographical area often form support-groups to assist each other in achieving a rapid cryopreservation in the event of death. Emotional bonding and friendship sometimes develop in these support-groups. The first persons to be reanimated will likely be the friends, spouses and parents of people who helped to cryopreserve them. Those reanimated will have a strong incentive to reanimate their friends and loved-ones. A vast chain of human connections will drive the reanimation process.

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The ultimate objective of cryonics is the indefinite maintenance of the physical basis of consciousness and the "self" through cryopreservation. If personal identity and consciousness are entirely embodied in the physiology of the brain, why does consciousness and identity seem to survive the gradual replacement of brain molecules with the passage of time. "Self" seems like a candle-flame — it survives despite the fact that all the atoms are continually being replaced. But the correspondence between brain activity and consciousness indicates that a mind is less ethereal and more likely to have a preservable physical basis than a candle-flame.

Some people imagine that cryonics requires materialism & determinism for personal identity to be cryopreserved. But free will (appropriately defined) need not preclude a material-based mind. People inspired by Roger Penrose have imagined that personal identity has some basis in quantum mechanics and cannot be cryopreserved. Yet if personal identity can survive for years at room-temperature, why would it not survive decades at cryogenic temperatures?

The biological basis of memory, consciousness and personality seems to be more of a scientific question than a philosophical one. Yet close attention to this issue yields some baffling paradoxes. If it is possible to build a perfect atom-for-atom reconstruction of a person — whether that person is currently cryopreserved or living — will the duplicate have the same identity as the original? What if twelve duplicates are created?

Subjectively, one's identity seems to be a discrete, unaltered entity which continues from childhood through adulthood, despite the accumulation of experiences. Identity seems to be something which cannot, by its nature, gradually become something else. But if a child can retain identity while growing into an adult — and in the process be experiencing molecule-by-molecule replacement of all molecules — why couldn't Bill Gates be gradually transformed into the Pope? Continuity between personal identities seems a violation of the nature of identity and the sense of self. But if self and consciousness have a material basis, such paradoxical questions are unavoidable.

Similar questions can be raised in connection with the uploading of human minds to computers, where backups and discrete modifications of data are done easily. Hans Moravec discussed such questions in his book MIND CHILDREN. Nonetheless, it is reasonable to question whether human personality is reducible to "information" — or whether human identity can survive in a nonbiological environment.

For more material related to the philosophical questions raised above, see my essays:

     The Duplicates Paradox,
     A Case for Free Will AND Determinism,
     Comments on Two "New Age Physics" Books,
     The Copenhagen Interpretation of Quantum Mechanics and
     Artificial Intelligence and the Preservation of Mind

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Many people ask: "Where does the soul go when you are cryopreserved?" — to which one might reply: "Where does the soul go when you are asleep or unconscious?". One answer might be that the soul is quiescent in all these conditions and has no need to go anywhere. The Catholic Church has strongly condemned the destruction of cryopreserved human embryos — regarding the soul as being associated with a cryopreserved entity.

To cryonicists, cryonics is a medical procedure unrelated to religious issues. Medicine has doubled the average life expectancy in the last hundred years. It is hard to for cryonicists to understand why it would be an affront to religion for life expectancy to be increased even a thousand-fold. Chapter 5 of GENESIS names six Biblical figures who lived over 900 years, including Adam (930 years) and Methuselah (969 years). In the face of eternity — or even a billion years — it is strange to imagine that an extra thousand years of life would thwart God's plan for human mortality.

Without divine revelation it is presumptuous to make assumptions about God's ideas of an appropriate lifespan for a given era. If God wanted thousand-year lifespans in the time of Genesis and 40-year lifespans in the Middle Ages — who is to say what lifespan is within His Plan in the Age of Cryonics? If cryonics is regarded as a life-saving technique similar to other heroic medical procedures, such as heart transplantation or experimental drugs, refusing cryonics would be suicidal — and most religions frown on suicide.

A religious problem might concern whether cryonics & anti-aging science greatly extends human lifespan or eliminates death entirely. It is only the complete elimination of death that seems to trespass on religious grounds. Although many cryonicists speak of "immortalism", the possibility (or inevitability) of death by accident, murder or suicide will never be eliminated — so it is presumptuous to speak of cryonics eliminating death. (For a more detailed treatment of this subject, see my essay Some Problems with Immortalism).

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Is it immoral to spend money on a doubtful last grasp at life like cryonics, when the same money could be used to save the lives of hundreds of malnourished Third World children? In this view, cryonics is an example of egotistical selfishness and greed. Is there room for cryopreserved bodies in a world that is grossly overpopulated at present, and is headed for a more serious population crisis in the future?

Most cryonicists tend to respond to these ethical criticisms on technical rather than ethical grounds. A thousand years ago Europe seemed to be overpopulated when famine and pestilence was common. Nearly two hundred years ago David Ricardo argued that the Iron Law of Wages guarantees that the Masses can never experience a standard of living above the minimum necessary for subsistence — because any increase in production would quickly be followed by an increase in reproduction.

But technology has made production outstrip reproduction in the Developed World. Overpopulation is only a problem in the Underdeveloped World, where reproduction is high and technology is low. Overpopulation is a function of technology — and where technology & economic freedom make each person a net contributor to world wealth, rather than a net drain, overpopulation is not to be feared. Much of the human population of the earth is crowded into urban areas — while most areas are sparcely populated land & ocean.

Cryonicists tend to be optimistic futurists and technophiles, so they often believe that technology can solve all problems. Technology can eliminate pollution, they say. Nanotechnology will produce food in abundance and will catapult all other fields of technology into an intense rate of progress. Skyscrapers & ocean-living could provide ample room from decades or centuries of population growth. As space travel becomes cheap, the Earth's human population will be dwarfed by the vastness of space. Space colonies in artificial enclosures will have access to vast energies of the Sun and practically unlimited room.

The desire to live as long as possible need not be viewed as an inhumane desire. If uploading to a computer were possible, micronization of computer circuits might mean that millions of minds could inhabit relatively little computer space while consuming relatively little energy. If cost is the ultimate criterion by which the desire to live forever is to be judged, is there some price at which this desire is no longer inordinately selfish? Cryonics is expensive today because relatively few people choose it. If thousands or millions of people were cryopreserved, economies of scale could drive the cost very low (liquid nitrogen is not expensive).

It is also often argued that death is necessary to remove rigid old minds from positions of power so that humanity can progress. But if technology eliminates aging, minds could continue to grow without becoming rigid or inflexible. Hundreds of years of accumulated wisdom by minds that do not grow old could prove to be the most valuable resource available to humankind. Such individuals would be more far-sighted and more concerned about the quality of the future environment, which they themselves would expect to inhabit.

Ethical issues related to cryonics are discussed in greater detail in my essay Why Life Extension?

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The majority of people regard a greatly extended lifespan as personally undesirable. Interviewers seem genuinely baffled when they ask cryonicists, "Why would you or anyone want to live forever?" Cryonicists too are baffled by the question — why would anyone want to die? (It has been mentioned that greatly extending lifespan is different from wanting to "live forever".)

For many people, a life of physical or psychological pain is not worth living. To a cryonicist it appears that most people must live lives of chronic boredom, depression, resignation and despair. People who have followed the formula of school, career and family often regard their lives as completed — as if they can't think of anything else to do. They may imagine cryonicists to be people with desperately unfulfilled lives.

Some people will not become involved in cryonics because too many things could go wrong, and there is no 100% certainty that the procedure will work. People who opt for cryopreservation, however, do not require 100% certainty, because even a small chance is regarded as better than no chance — especially when the reward of success is viewed as being enormous.

Others believe that within the next 50 years science will cure aging or devise ways to transfer human consciousness to computers — and that cryonics arrangements are unnecessary. Such optimism overlooks an important point: death can occur at any time before the anticipated technology is achieved. A person in cryopreservation can "patiently" wait for science to advance, but a person rotting in the earth cannot.

A final psychological barrier many people experience with cryonics concerns the association with death. The topic of death is gruesome. Cryonicists seem ghoulish. Contemplating one's own mortality can be painful, like looking at the Sun. Most people would rather think happy thoughts. Death seems remote, especially for a young person. Many people refuse to prepare for death — as exemplified by the fact that 60% of people die without having made a Last Will and Testament. The earlier a person begins to think-about and prepare-for death, the better are the chances that it will not strike as a devastation, especially in the case of cryonics. This could include preparing for the death of loved-ones, as well. Too often, people have contacted cryonics organizations only after their loved-one is close to death or has already died — too late.

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Before a cryonics organization can cryopreserve a person it is essential that all of the legal and financial arrangements have been formalized. Too many people assume that they can make these arrangements on their deathbed or that the arrangements can be made by others after death. But cryonics organizations usually refuse to handle "last minute" cases.

Cryopreservation involves a great deal of up-front expense and legal risk. A cryonics organization cannot risk spending large amounts of money on services, equipment and transport costs only to discover that the person had written a Will requesting burial, that financing is inadequate, that relatives vehemently oppose cryonics or that the funding is tied-up in probate. For this reason, cryonics organizations require that the people they cryopreserve have proven intention & financial capability well before death as part of the sign-up process & paperwork. A formal cryopreservation agreement is signed and notarized along with other paperwork, such as anatomical donation. Most people finance cryonics through life-insurance. It is too late to obtain insurance after one has cancer, AIDs, etc., which is another reason why sign-up should be done well before death. Insurance is cheap for a healthy young person, but extremely expensive for a diseased and/or elderly one.

Cryopreservation can only begin after legal declaration of death by a physician or nurse. Ideally, a mortician or cryonics team will immediately begin cooldown and restoration of circulation using a heart-lung machine to ensure that tissues are kept alive. Without those procedures circulation quickly becomes difficult to restore without reperfusion injury. Soon cells would begin to die from lack of oxygen & nutrient ("ischemic damage"). If hours pass, the brain will begin to self-destruct with acid — resulting in dissolution of brain tissue. (For technical details, see Ischemia and Reperfusion Injury in Cryonics and Quantifying Ischemic Damage for Cryonics Rescue )

With circulation restored, anticoagulants and other additives to prevent tissue damage can be injected into the patient. External cooling reduces the metabolic rate, thereby slowing the damage following legal death (See Emergency Preparedness for a Local Cryonics Group). Once the patient has been cooled to approximately 10ºC blood may be washed-out and replaced with organ preservation solution. The patient is then shipped to a cryonics facility at just above water-ice temperature (0ºC). It is important that ice formation not occur because freeze-damaged blood vessels would not allow for perfusion with cryoprotectants.

At the cryonics facility organ preservation solution (or blood) is replaced with vitrifying cryoprotectant, a process that can take a few hours (for more details, see my essay Perfusion & Diffusion in Cryonics Protocol). Then the patient is cooled rapidly with nitrogen gas to the solidification temperature of the cryoprotectant (-120ºC to -130ºC) and held at that temperature until temperature is uniform. Once solidification has occurred uniformly the patient must be cooled slowly to liquid nitrogen temperature (-196ºC) to prevent cracking from thermal stress. (For more details on cryonics cooling technology, see computer-controlled cooling boxes)

The patient is then stored head-down in a dewar or cryostat — a large thermos bottle which contains both the patient and liquid nitrogen. If boiloff were excessive due to catastrophic negligence, the upside-down position protects the head. The storage procedure is not vulnerable to electrical power failure, although the liquid nitrogen levels must be topped-off every week or two. Because the patient is suspended in liquid nitrogen (and because of the association with "suspended animation"), cryopreservation is often described as a "suspension". Literally, the patient cannot be said to be "suspended" in liquid nitrogen because the patient is more dense and will sink rather than float, despite being somewhat more buoyant (as is the case in any liquid).

To assist in rapid response to sudden accident, most cryonicists wear identification bracelets and/or necktags containing the phone number of their cryonics organization. But despite the most extensive preparations beforehand, less than a fifth of signed-up cryonicists are cryopreserved under what could be called good conditions. Some are not cryopreserved at all or are autopsied. Some die so suddenly and without warning that they have long periods of ischemic damage. Nearly half have experienced severe brain injury prior to death due to Alzheimer's Disease, AIDs, or long periods of shock during the dying process.

Some people think that the likelihood of dying suddenly is so great that it is futile to make cryonics arrangements. But the vast majority of people die slowly in a hospital. Even those who die of accident usually do not die instantaneously, but die in a hospital. Better technology, greater acceptance of cryonics procedures by medical & legal authorities and wireless alarm devices connected to heart monitors are expected to greatly improve the odds. (For the probabilities of various kinds of death, see my essay Causes of Death).

To read a personal description of my first "hands-on" cryonics local response case, see The First Cryonics Case in Toronto, Canada. For a better summary of cryonics protocol see my essay Cryonics Protocol — A Summary.

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Many people question whether cryonics organizations have integrity and/or long-term survival capability. Cryonics organizations are not money-making rackets, they are the creations of people who are trying to build their own lifeboats. Cryopreservation funding is partly spent on cryopreparation, but most of the money is held on behalf of the patient so that interest in the principal can pay for long-term cryostorage. Cryonics organizations are controlled by people wanting to save their own lives and the lives of their loved-ones. Survival means more to them than money — money is a means to survival. Nonetheless, good intentions don't guarantee competence.

One of the first cryonics organizations was the Cryonics Society of California, formed in the mid-1960s. Robert Nelson, the principle organizer, froze many people, placed them in storage and received some money for this. But he also took many charity cases and pay-as-you-go cases on the expectation that future proceeds would make up the difference. Because his revenues were inadequate, Nelson could not maintain his clients in a cryopreserved state and allowed them to thaw (hidden in an underground crypt which he would not allow others to inspect). He maintained a fraudulent facade until he was exposed and sued. The underground crypt was in a cemetery in the city of Chatsworth, California. In cryonics circles the word "Chatsworth" has become synonymous with the disaster — it is a cryonics equivalent of the Space Shuttle explosion.

Currently existing cryonics organizations are more trustworthy and fiscally prudent than the Cryonics Society of California. No cryonics organization currently accepts pay-as-you-go funding. The full capital must be paid up-front so that perpetual care can be paid for from the interest on that principle (anticipated as 1% per year by Alcor). At present there are five organizations in the world offering cryonic storage services to the public. All but one of them are in the United States:

The Cryonics Institute (CI) is originally the creation of Robert Ettinger. Ettinger is acknowledged to have launched the cryonics movement with his 1964 book The Prospect of Immortality). CI is governed by a Board of Directors elected by the members. The Cryonics Institute takes pride in its low prices and resistance to price increases. After a membership fee of $1,250 the cost of cryonics arrangements to cryopreserve a whole body with CI is $28,000. (An alternate plan allows for a yearly membership fee of $120 and $35,000 cost.) $8,000 pays for perfusion, and $20,000 acts as the maintenance fund. ("Perfusion" actually includes the cost of the storage capsule, the replacement of blood with cryoprotectant, and other costs involved in placing the deanimated person into the capsule). The cryostats used by CI are fiberglass-type units originally made in-house, but now manufactured by a contractor.

Alcor was founded in 1972 by Fred and Linda Chamberlain, in the wake of the collapse of the Cryonics Society of California. The name "Alcor" refers to a faintly visible star in the Big Dipper which was used in ancient times as a test of visual acuity. Alcor charges $150,000 to cryopreserve a whole body and $80,000 to cryopreserve only heads ("neuros").

Disagreements among American Cryonics Society (ACS) Board Members caused a splinter group to form the International Cryonics Foundation (ICF) in the early 1990s. Both ACS and ICF are non-profit suspension-arranging organizations which contracted for suspension services with the profit-making organization Trans Time. Trans Time's role in the past was purely technical: perfusion and storage of de-animated patients. Nonetheless, Trans Time and ACS ultimately feuded, with ACS removing their patients and Trans Time adding sign-up to its services. ACS has recently arranged a "merger" of sorts with CI, but ACS members have their distinctive financial arrangements.

Trans Time, ICF and ACS have far fewer members than Alcor or CI. Alcor has emergency rescue teams that travel to the location of dying members and stand-by to administer CPR, anti-ischemic medications and rapid cooldown. CI or ACS Members can get Standby from Suspended Animation, Inc., a company that subcontracts to cryonics organizations and does not deal directly with the public. For CI Standby is an optional extra requiring extra expense, but for ACS Standby is included in the price. All organizations now use vitrification cryoprotectant and protocol that can virtually eliminate ice-crystal formation & damage in the brain (as seen by brain ultramicroscopy). CI does not offer a neuro option, uses only open-circuit perfusion and relies on local funeral directors to implement protocols. CI employs a research cryobiologist and began offering vitrification in 2005.

Many people question whether a cryonics organization can survive for at least a hundred years — which it surely must if the procedure is to work. The Hudson Bay Company, the Catholic Church, Ford Motor Company, the Red Cross, Dupont, etc. are examples of organizations that have lasted many decades, centuries or (with the Catholic Church) millenia. Many of these organizations are run by people who are far from perfect — yet the organizations have survived and contractual obligations have been met. But it is also true that there are many frauds, cultists and incompetents in the world and that many organizations fail every year. Cryonicists have powerful incentives to create organizations that are honest and durable — their survival depends upon it.

Some people think that after the cryonics patient has paid money and is in cryostorage that there is no incentive for the organization to continue service (storage) since the person is dead and will soon be forgotten. It may be easy to forget a person buried in the ground, but it is not so easy to forget a person who is in cryostorage. The people who run cryonics organizations expect themselves to eventually be in cryostorage and are betting their lives on the process, so they take care of their patients. Many cryonicists have loved-ones in cryostorage. Each cryopreserved member is precious — symbolically if not actually — and a threat to one is a threat to all. Those who run cryonics organizations defend all the members in storage like ferocious mother hens. The first people revived will be the last people stored — because they will have been stored with the least amount of damage. Gradually, as repair capabilities improve, patients stored earlier — under less optimal protocols — with be repaired and reanimated.

Cryonics organizations are not for sale to the highest bidder — ie people who think that cryonics might be a profitable business even though they have no desire themselves to be cryopreserved. Directors are selected on the basis of ability and dedication to the ideals of cryonics. At the Cryonics Institute Directors are elected by the signed-up members. At Alcor new Directors can only be added to the Board by the decision of existing Directors.

There are no financial incentives to join a cryonics organization, only financial costs. No cryonics organization issues stock or pays dividends. Employees are usually not well paid and Directors receive no pay. The organizations are run by members for the purpose of their survival and the survival of their friends and loved-ones.

For a more detailed comparison of the cryonics organizations, see Comparing Policies and Procedures.

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In order to dispose of human remains, it is necessary to get a death certificate signed by a physician, and to get a certificate for the disposal of human remains from a local authority. Members of the Cryonics Society of New York (CSNY) discovered in 1974 that even these certificates were not adequate for their attempts to preserve the cryopreserved remains of three deceased persons. A letter from the State of New York Department of Public Health declared, "...we do not consider these bodies to be decently buried as required by section 4200 of the Public Health Law... You should note that violation of the Public Health Law is a misdemeanor. In addition, the Commissioner of Health may assess a penalty of One Thousand Dollars a day for each day you fail to comply with section 4200." The bodies of the three people were returned to their relatives, and CSNY ended its cryopreservation program.

The most dramatic clash between cryonics and legal authorities, however, occurred in the case of Dora Kent. Dora Kent was the 83-year old mother of Saul Kent, a man who has done much to promote life-extension and cryonics. In December 1987 Saul Kent moved his mother to the Alcor facility in Riverside, California where a cryopreservation team froze her. The cryopreservation team included a medical doctor who was not present in the facility when Dora Kent's heartbeat and breathing stopped shortly after midnight. Although the physician signed the death certificate the next day, the cryopreservation team proceeded with the cryopreservation protocol immediately after Mrs. Kent's death. Because she was a neuro case, Dora's head was removed and cryopreserved.

Two weeks later, on January 7, 1988, Coroner's Deputies entered the Alcor facility with a search warrant, looking for Dora Kent's head. When the deputies discovered that the head had been removed, they handcuffed 6 members of the cryopreservation team and took them to the Riverside County Jail. Although the team was released, 5 days later the Alcor facility was attacked by a SWAT team and by UCLA police, who ransacked for 30 hours, confiscating Alcor's records, $5,000 worth of medicines and 8 computers as well as other equipment. Alcor had purchased items from the UCLA Surplus and Excess Property Department, and some of these items still had the letters "UCLA" on them. Alcor was able to obtain a Temporary Restraining Order to keep the patients from being thawed.

Another example of the kind of legal problems cryonicists face is the case of Dick Clair Jones, the Emmy Award-winning producer-writer of "The Facts of Life" and "Mama's Family". When Jones was admitted to a Los Angeles-area hospital as a result of a life-threatening AIDS-related infection, the hospital declared that it would not co-operate with Alcor, or release Jones' body to Alcor after death. Moreover, the State of California Department of Health Services (DHS) took the position that "Alcor does not have the legal right to have or hold human remains", holding that state law authorized only four methods of disposal of remains: (1) cremation, (2) burial, (3) shipment out-of-state, and (4) donation for scientific purposes. The DHS declared that anything not specifically legal must be illegal. Dick Jones and Alcor filed suit against both the hospital and the DHS. A court order was obtained against the hospital, which cooperated with Alcor when Jones was suspended upon his death in December, 1988. Alcor fought the DHS in California courts, ultimately winning in June, 1992.

Dick Jones had been active in the cryonics movement for 20 years prior to his death. He had written promotional literature for Alcor, and was a good friend of Saul Kent, whom he named executor of the Jones Estate. The Estate plan consisted of two Trusts. One Trust left $200,000 to his family, and the other Trust left the balance of his Estate (estimated in the millions) to Alcor. Fifty-six hours before Jones died, he signed a new Will and amended his existing Trusts to split his Estate between Alcor and his relatives. A legal battle ensued over whether Jones was legally competent to change his Will at that time, and whether his sister had induced him to do so. The lawyers on both sides of the case earned as much money as the litigants before a settlement was achieved.

Some cryonicists have participated in the political struggles to legalize euthanasia. Although cryonicists do not believe that cryopreservation is suicide, most support the "right to die" in the legal sense. In particular, Thomas Donaldson (a PhD in Mathematics) was concerned that his brain cancer would destroy too much of his memory & identity before killing him. Dr. Donaldson fought in the California courts for the right to be cryopreserved before his legal and natural death, but he lost his case. Other cryonicists would also prefer to be cryopreserved at a time of their choosing — to reduce suffering, to gain control of the moment of death and to eliminate the deterioration which often accompanies a slow death. Person's with Alzheimer's Disease have often allowed their cryonics coverage to lapse due to the deterioration in their mental faculties — again a threat to memory & identity.

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In the mid-1990s Alcor did a study of their costs for cryopreparation of a person, and the maintenance costs of a person's cryostorage:

                                      Whole Body    Neuro

CRYOPRESERVATION COST:              $27,469.67     $18,908.76    

YEARLY COSTS:                         Whole Body    Neuro

    Liquid nitrogen                    318.46     73.00
    Floor space                         33.75      2.50
    Custodial labor                    135.00      8.00
    Amortized Dewar/Alarm              296.67     59.26
    Administrative charge                3.00      3.00
    Utilities and overhead              67.50      5.00
                                       ------     -----
                                       854.38    150.76

Nominal interest on the Patient Care Fund is composed of two parts: (1) a portion corresponding to anticipated inflation and (2) a real interest portion. Alcor assumes that the real interest portion will be at least 2% (a reasonably conservative estimate). The 2% is allocated half for maintenance costs (1%) and half for capital appreciation (1%). Thus, calculating the amount of capital required for a 1% real return to pay maintenance costs gives (854.38/0.01) = $85,438 for whole-body and (150.76/0.01) = $15,076 for neuro, total maintenance capital. Adding cryostorage and cryopreparation costs gives: 85,438 + 27,469.67 = $112,907.67 for whole-body and 15,076 + 18,908.76 = $33,984.76 for neuro. Using these figures, the decision was made to raise the rates to $120,000 and $41,000 for whole-body and neuro, respectively. This was to provide a buffer against a few years of inflation, but no one is pretending that there will be no more price increases.

Although these figures are out-of-date, they indicate the kind of thinking that can go into calculating costs for cryonics. The high cost of cryonics is not an indication that someone is being economically enriched. Quite the opposite, most cryonicists who promote cryonics are motivated by a hope for the survival of themselves and their loved-ones — not economic gain. Most cryonicists find cryonics to be costly, and those who draw earnings from cryonics receive small salaries. Most of the money paid for cryonics services is not even spent — it is maintained in a fund on behalf of the person who paid the money for perpetual care and for reanimation costs.

Alcor charges US$80,000 for preserving the head only ("neuro") and US$200,000 for cryopreserving the whole body. ACS has a similar fee structure. The Cryonics Institute (CI), which does not offer the "neuro" option, changes US$28,000/$35,000 for whole-body cryopreservation, plus a membership fee. Reasons given for such a radically lower cost include: (1) CI is largely a volunteer organization with few paid staff, (2) CI spends only $8,000 on cryopreservation costs (3) CI does not include Standby or Transport services in its fees, which can be very costly if not done by a funeral director. (CI Members wanting Standby can contract with Suspended Animation, Inc.)

Although cryonics sounds very expensive, most people arrange for payment through life insurance. For most people, particularly those who are young and healthy, a good life insurance policy costs less than a cigarette habit. While life insurance may be adequate for short-term protection, in the long-term it should be supplemented by a diversified portfolio of equities to protect against inflation.

For a more detailed comparison of cryonics organization costs, see Comparing Policies and Procedures.

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Some cryonicists have been exploring the feasibility of permafrost burial combined with chemical preservation and/or desiccation. This procedure would not only be cheaper (less than $10,000), but it would be less vulnerable to failure due to legal, financial or organizational problems. The Cryonics Society of Canada has shown interest in permafrost burials. The Cryonics Society of Canada has assisted in two permafrost burials, one in Inuvik and one in Yellowknife. A third Yellowknife patient made independent arrangements.

The procedures of permafrost burial are very primitive and the preservation is grossly inferior to that provided by liquid nitrogen temperature. Permafrost temperatures alone are not adequate to preserve structure. When combined with chemical preservation, permafrost temperatures could be of value, but no research or rescue team efforts have been mobilized to make this a workable option.

For more information about Permafrost burial, see my collection of articles The Permafrost Papers

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British Columbia is the only State or Province known to cryonicists to have a law against cryonics. The Cemetery and Funeral Services Act, Bill 42, became law in British Columbia in April 1990. Under the heading "Arrangements Forbidden" is Part 5, Section 57: "No person shall offer for sale or sell any arrangement for the preservation or storage of human remains based on cryonics, irradiation or any other means of preservation or storage, by whatever name called, that is offered or sold on the expectation of the resuscitation of human remains at a future time."

The interpretation of Section 57 is the responsibility of the Registrar of the Cemeteries and Funeral Services Branch of the Ministry of Labour and Consumer Services. How Section 57 would be interpreted in a practical situation is still anyone's guess, but a previous Registrar expressed the opinion that a person making arrangements with cryonics organizations outside of British Columbia would have no problem. In practice, legal & medical authorities in British Columbia have responded to cryonics cases as if cryonics were strictly illegal.

For more information about British Columbia's anti-cryonics law, see my article British Columbia's Anti-Cryonics Law.

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My essay A History of Cryonics provides a concise summary of the historical context of cryonics. Charles Platt wrote A Short History of Cryonics, although it is a decade old and half of the history is about CryoCare. There is a Wikipedia entry on Cryonics and a Wikipedia entry on Life Extension that both have information about cryonics. (Wikipedia is a web-based encyclopedia.) The American Academy of Anti-Aging Medicine has a good review of cryonics directed specifically toward physicians entitled Why Cryonics?

The book ENGINES OF CREATION by K. Eric Drexler has probably had more influence on the growth of cryonics than any other book. Drexler's book makes a case for the idea that future Nanotechnology will result in molecular-scale machines which will be able to repair tissue damage associated with aging — eliminating aging — and repair freezing damage associated with cryonics.

All of the cryonics organizations offering cryopreservation services have literature packs, and many sell books. The most comprehensive collection of links to cryonics-related web pages is the cryonics section of the DMOZ Open Directory Project . My cryonics page lists all of my own essays on the subject of cryonics. The best source of news about cryonics (and lots of "shooting the breeze") is CryoNet.

In some large cities it is possible to meet other cryonicists in person at meetings in public restaurants or cafes arranged on the web through Cryonics Meetup.

My Cryonics — Frequently Asked Questions (FAQ) also has more up-to-date information than this essay and the cryonics section of my website has more information about the technical and scientific basis of cryonics than any other source on the internet. My website also contains a life extension/cryonics survey along with results and comments from nearly a thousand people who have taken the survey (which gives insight into pro-cryonics and anti-cryonics sentiment).