Cryonics and You

An Introduction to Cryonics

Converted to HTML, December 20, 1995

Welcome to the Future

Cryonics is about the future. It is about our personal future, the future of humanity, and the relationship between the two. Predicting the future is a dangerous business, and this booklet does not pretend to be a crystal ball. Sometimes, however, there are trends in science and technology that are so overwhelmingly powerful, some consequences seem inevitable.

This booklet, and the science of cryonics, are based on a vision of the future that we at CryoCare Foundation believe to be both foreseeable and compelling. It is a future with computers the size of bacteria, cures for all of today's diseases, and people who live in good health and youth for centuries. If these developments sound too fantastic to be believed, you need read no further. If, however, you can imagine a future of such dramatic potential, please read on.


The Future of Medicine

What will medicine be like 100 years from now? If physicians a century ago had been asked this question, how many would have foreseen antibiotics, gene therapy, and MRI machines? Probably none. In fact no radiologist could have foreseen MRI (magnetic resonance imaging) even 30 years ago. The developments leading to MRI were occurring in computer science and physics labs, not radiology departments. Sometimes we have to look outside medicine to see where the next medical breakthroughs will come from.

In 1959 Nobel laureate and physicist Richard Feynman presented a paper entitled, "There's Plenty of Room at the Bottom." Feynman proposed building tiny machines that would build still smaller machines until individual atoms could be manipulated like building blocks. He predicted that such a capability would have a profound impact on the science of biology and technology in general.

In 1981 MIT engineer Eric Drexler published a technical paper, later followed by a book in 1986 titled Engines of Creation. He outlined how protein engineering could lead to the capabilities that Feynman had described. Drexler foresaw a whole new technology, which he called "nanotechnology," that would emerge from the ability to engineer materials on a molecular scale. In particular, he foresaw general purpose "assemblers" that would build almost anything, from powerful computers the size of bacteria to microscopic "nanobots" able to do surgery on individual cells.

Nanotechnology and nanoscience are now buzzwords and have merited cover stories in respected journals such as Science and Nature. The Japanese government is sponsoring a billion-dollar initiative to develop methods for engineering at the molecular level. Think tanks and major corporations in the U.S. are now employing scientists to study the engineering applications of nanotechnology. The capability to actually build the devices foreseen by Feynman and Drexler will emerge slowly over decades, but the medical applications are already clear.

Medicine today does not heal patients. It depends almost entirely on patients to heal themselves, and is not always successful. Traumatic injury, massive infection, or the genetic alterations of viruses, cancer, and aging often leave the body unable to heal itself.

During the 21st century this will slowly change. Vast new arsenals of medical tools will become available. These tools will include microscopic robots able to perform surgery from within the body, engineered viruses able to repair genetic defects, and even intelligent cell repair organisms that are able to enter and heal cells one molecule at a time.

Medicine will enter a new era. Detailed understanding and control of genes will allow the conquest of infectious diseases and cancer. Engineered organisms will be able to repair injuries that the body cannot heal by natural means. Specialized genetic programs will make it possible to regrow injured or lost organs and limbs. Eventually even the genetic changes of aging will be understood and controlled. Lifespans will increase dramatically.

This is CryoCare's vision of the future: a medicine based on mastery of the molecular basis of life. We are all made of atoms and molecules. The difference between health and disease, youth and old age, even life and death, is ultimately a difference in the arrangement of our atoms. Medicine will not reach its fullest potential to heal and restore health until it is able to analyze and rearrange atoms in sophisticated ways. Such a time is still decades away. But it will come.

Introducing Cryonics

In 1964 physics professor Robert Ettinger suggested that low temperature preservation (cryopreservation) might enable today's dying patient to be treated by tomorrow's medicine. After tissue has been cooled to the temperature of liquid nitrogen (-196 degrees Celsius), it can be maintained for centuries, if necessary, without change. This idea-- maintaining dying patients at low temperature until they can be cured by future medical technology--has come to be called cryonics.

Cryonics is controversial because freezing an entire body is not reversible today. Although many individual cells remain viable and able to resume function after freezing and thawing, the ice crystals that form between cells cause extensive tissue damage. This damage prevents the return of normal organ function. Freezing, within the limits of medicine today, is a fatal injury.

Will the injuries of freezing always be irreversible? This is the central question of cryonics. If cell repair technologies of the future can heal injuries produced by freezing today, then freezing is not truly fatal and cryonics is a viable path to the future. Of course this is speculative, and therein lies the controversy.

Cryonics Today

Cryonics would have remained idle speculation were it not for another idea proposed by Robert Ettinger. He addressed the question of how a procedure that is believed to be fatal can be applied legally to dying patients. His answer was to wait until a patient's breathing and heartbeat stop before starting cryonics procedures. The patient is then legally dead, and cryonics can do no additional harm.

The rationale for applying cryonics after legal death is that legal death and real death are often not the same. Patients dying of a terminal disease are usually given a "no code" or DNR ("do not resuscitate") status, which means that no attempt will be made to resuscitate them if their heart stops. Very often, though, they could be revived if an attempt was made. The short period of time between legal death--which is when the heart stops--and irreversible death, when the brain is terminally injured, creates a window of opportunity for cryonics. Although having to wait for the legal death of terminal patients creates substantial logistical (and sometimes medical) problems, it is a perfectly legal way to implement cryonics today.

At the time of writing, 60 cryopreserved patients are in the care of six U.S. organizations that offer cryonics services. In addition, more than 700 other people have made the necessary legal and financial arrangements to have cryonics available for them and their families. These people include doctors, scientists, students, crafts people, teachers, and children--people from all walks of life who share a common desire to reach beyond the limits of today's medicine.

CryoCare Foundation

In 1993 a group of long-time cryonics activists and professionals gathered together. Their goal was to combine the best features of existing cryonics companies with important new features in order to create the best possible cryonics organization. The result was CryoCare Foundation, a non-profit corporation that manages cryonics services for its members.

CryoCare Foundation is a non-profit administrative organization. It does not do the "hands-on" work of cryonics. Instead, it obtains the best cryonics services available from independent contractors, and offers those services to its members within a unique protective legal structure that guarantees the greatest possible security and stability in the long term.

Some people are confused to learn that CryoCare does not have its own medical or storage facilities. But we chose to structure our company this way for several very important reasons.

First, we believe that free competition among service providers is the best guarantee of efficiency and quality. As cryonics becomes increasingly popular, we expect to see more companies offering various services. CryoCare hopes to contract with as many of them as possible, so that they will be motivated to compete for our business, and we will be able to offer our members a range of choices instead of forcing everyone to accept a single option.

Second, we believe that specialization encourages higher standards and reduces timewasting policy debates. In an organization that tries to deal with all aspects of cryonics, from public relations to long-term maintenance of frozen patients, financial policies and planning can be very difficult issues to resolve. By delegating specific roles to our service providers, we simplify CryoCare's tasks. We perform outreach to new members, we handle the legal paperwork of cryonics, we take legal responsibility for our patients, and we supervise their care. We employ specialists to do actual cryonics procedures, and we monitor their performance.

Third, by dividing the functions of cryonics into smaller units we recognize that cryonics activists have always been highly individualistic people who tend to work harder and more productively as entrepreneurs than as a cooperative group.

Fourth, by separating CryoCare from its service providers we enhance the security of our patients. The procedures (described below) that precede human cryopreservation are relatively new, and some people find them disturbing. In the future, they may even create public backlash. But once a patient has been frozen, maintaining that person in liquid nitrogen is not a controversial business because the same storage technique is widely used by many institutions to preserve organs and tissue samples. Therefore, we feel it may be prudent to separate this business legally and financially from other areas of cryonics that are not so widely accepted.

Cryonics Procedures

A typical scenario for a human cryopreservation begins in a hospital, nursing home, or home hospice setting where a CryoCare member is seriously ill. In consultation with local physicians, the member's condition is evaluated by medical personnel from the service employed by CryoCare. If the patient's condition is critical, a transport team is dispatched to stand by on a 24-hour basis.


As soon as the heart stops, legal death is pronounced by an independent attending nurse or physician. The Cryocare member now becomes a CryoCare patient, and the cryonics transport team begins its work. The patient is lowered into a water-ice bath, and blood circulation and breathing are artificially restored by a Heart Lung Resuscitator (HLR), which administers cardio-pulmonary support (CPR). Intravenous lines are established and special medications are administered to protect the brain from damage that might otherwise be caused by lack of oxygen.

Thirty minutes later, major arteries and veins are surgically accessed and the patient is placed on cardiopulmonary bypass. This means that blood is now circulated through a heart-lung machine that takes over the function of the patient's own heart and lungs. CPR is no longer necessary, and is discontinued. A heat exchanger in the heart-lung machine swiftly reduces the patient's temperature to a few degrees above the freezing point of water.

If the patient is outside of Southern California, the blood is replaced with an organ preservation solution that is commonly used to preserve transplanted organs in cases where the donor and the recipient are separated by large distances. The patient is then packed in water-ice for air shipment to the surgical facility maintained by our medical services provider, BioPreservation, located about forty miles east of Los Angeles.

Cryoprotective Perfusion

At BioPreservation's facility a surgeon attaches cannulae to the great vessels of the heart. A solution containing glycerol--an anti-freeze agent that inhibits freezing damage--is gently introduced via the major arteries. Its concentration is gradually increased during a four-hour procedure known as cryoprotective perfusion.

Personnel use state-of-the-art medical equipment, including fiber-optic probes, to monitor all phases of this operation and confirm that glycerol reaches even the smallest capillaries of the brain.

After perfusion is complete, the patient is immersed in silicone oil for cooling to -79 degrees Celsius (the temperature of dry ice). This takes about 48 hours and completes the transport and perfusion phases of human cryopreservation performed on our behalf by BioPreservation, Inc.

Long-Term Care

Long-term care is the maintenance of cryonics patients for the indefinite future at -196 degrees Celsius, the temperature of liquid nitrogen. CryoCare's long-term care service provider is CryoSpan.

CryoSpan is a for-profit company founded in 1993. It is located in the same facility as BioPreservation but is independently owned and operated. CryoSpan has recently completed construction of an underground storage vault that has been certified by seismic engineers to withstand the largest earthquakes ever recorded in this area. CryoSpan is the only cryonics care facility to offer vault protection of all its patients against fire, wind, vandalism, or earthquakes. CryoSpan currently maintains 11 patients in large stainless-steel, high-vacuum insulated containers employing an innovative design to obtain the lowest liquid nitrogen boil-off rate per patient in the industry.

Remember, we at CryoCare retain all legal responsibility for our patients. If we are ever dissatisfied with the care being offered by an organization where our members are being maintained in the frozen state, and if we can't resolve these problems, we have the authority to transfer our patients to another company if necessary (assuming that patients' funds are sufficient). In this way, CryoCare patients receive unique protection from business or other failures of long- term care providers.


CryoCare has established a separate non-profit organization called the Independent Patient Care Foundation (IPCF) to administer the funds that patients leave for their long-term care. The IPCF exists solely for this purpose and will employ professional money managers to invest patient funds for security and long-term growth. IPCF bylaws require it to disburse funds at the request of CryoCare Foundation, only for patient care and administration. No exceptions are permitted.

Ideally, we believe that patient funds should be accounted individually. In other words, money that you set aside for your care should pay for your care only, and should not be pooled with funds from other patients. We also believe that you should receive a refund of any money left over in the future, when you can be successfully revived.

Implementing these principles is difficult, because they create legal issues which no cryonics organization has yet resolved satisfactorily. At the time of writing, CryoCare is negotiating with federal agencies. If you want an update on our status so far, please contact us for details.

Patient Advocates

CryoCare is the only cryonics organization that allows you to nominate someone (or a group of people) to oversee your care after you are cryopreserved. These Patient Advocates serve as "watchdogs" to insure that CryoCare always looks out for its patients' best interests when they can no longer speak for themselves.

Patient Advocates have the power to vote for a special class of CryoCare directors called Patient Directors, who vote on issues related to patient care. Under extreme circumstances a Patient Advocate can even intervene and require a patient to be transferred from one long-term care provider to another.

Problem Scenarios

In some cases, particularly when accidental death is involved, it is not possible to begin cryonics procedures promptly after the heart stops. There may be a wait of many minutes or even hours before the team can reach the patient. Brain injury is severe in such cases. By today's medical criteria, anyone whose blood circulation has stopped for an hour is very "dead."

But the real question is, what will future medicine define as "death"? Even today there have been astonishing cases of people who have fallen into snow drifts or drowned in cold water, and have been revived using current medical technology after literally hours without any detectable pulse, respiration, or brain activity. Of course, these cases are unusual. At normal temperature injury to blood vessels in the brain (such as blood clotting) may be irreversible after just five or ten minutes. Even in these cases, though, individual brain cells (neurons) remain alive and able to resume function for as long as an hour after the heart stops. If future medicine can heal and replace injured blood vessels, it should be able to resuscitate people who cannot be resuscitated today. If it can use microscopic devices to reverse chemical imbalances within injured cells, it should be able to revive people after an hour or more of clinical death.

Bearing this in mind, we can't say where the outer limits of resuscitation will be. For this reason cryonics procedures are still applied to patients who are far beyond the reach of today's medicine. We would be extremely short-sighted and arrogant if we assumed that medicine today is the best medicine that can ever exist.

Continuing to care for a patient with an uncertain prognosis is the morally and ethically correct thing to do. Many patients that we would call "dead" today are likely to be reclassified as "seriously ill, but treatable" in the future.


It costs money to provide emergency care and perfusion of a cryonics patient, and it costs more money to maintain patients in the frozen state. People with limited resources naturally want to minimize these expenses as much as possible.

Modern medicine has taught us that our most irreplaceable organ is the brain. We can transplant hearts, livers, kidneys, and lungs (sometime simultaneously!). We can suffer severed spinal cords. We can lose limbs. But our sense of identity--our memories and our sense of self--will survive all of these events.

By contrast, even minor injuries to the brain can fundamentally change who we are. Taken to the extreme, death of the brain is the absolute and incontrovertible death of the person. No other organ has this property.

Future medicine will have vast and general capabilities for tissue repair and regeneration. The healing of spinal injuries and regrowth of lost limbs and organs will be relatively simple for a technology with detailed understanding and control of gene expression. But the challenge of repairing a brain with extensive microscopic freezing injury will be much more formidable. Therefore, we believe that by the time medicine is able to repair this kind injury, growing a healthy new body will be easy by comparison.

How do we know that growing a new body "from scratch" is possible? First, the ability to do so is implicit in a technology that can understand and manipulate genes. Second, and perhaps more to the point, each person alive today was once a single cell. We know that a complete human being can be grown from scratch because this is how human life flourishes in the natural state.

Imagine the newly healed brain of a cryonics patient suspended in the fluid of a 22nd century "artificial womb." Genetic reprogramming of a single cell on the surface of that brain begins a process of growth and development that perhaps a year later appends to the brain a complete young adult body.

Bearing this in mind, if we preserve only a person's brain we may still enable "rebirth" of a whole new individual in the future--with the same identity and memories. This is the rationale for neuropreservation, which means cryopreservation of the brain only.

In the frozen state, neuropatients consume one-tenth the volume and a small fraction of the maintenance expense of whole-body patients. Neuropreservation therefore costs much less than whole-body cryopreservation, which is one reason why many CryoCare members have chosen the neuropreservation option. In addition, all CryoCare members who choose whole- body cryopreservation must consent to emergency conversion to neuropreservation if future economic problems or other difficulties make this conversion necessary for continued care. CryoCare will not allow the loss of a whole-body patient as long as the neuro option remains available.

Perfusion of a neuropatient is almost identical to that of a whole-body patient. When perfusion is complete, cephalic isolation is performed between the sixth and seventh cervical vertebrae. Because a brain by itself is an extremely vulnerable to damage, it is maintained within the cranium for protection and security.

Cryonics and You

What is your vision of the future? Some people see a future of overpopulation, resource depletion, and environmental ruin. Some people see a future not very different from the world today. Some people--perhaps most people--don't even think about it.

At CryoCare, we believe that the next one hundred years will bring more technological change than the last thousand years. These changes will render most of today's ideas about resources, population, and medicine quaint and obsolete. The result may be a world where people for the first time in history have the opportunity and resources to enjoy life without the prospect of progressive physical decline and imminent death. It may also be a world with frontiers that extend to the stars. We are not saying that such a future is certain, but it is physically possible.

At CryoCare, we believe that there is no higher value than that of an individual human life. If a doorway can be created between our world of today and the world of the future, we are more than ready to step through that door, since it offers the only rational hope of a vastly extended human lifespan.

We invite you to join us. For more information, call or write:

    CryoCare Foundation
    1013 Centre Road
    Suite 301
    Wilmington, DE 19805-1297

CryoCare Membership

For $9 a year ($15 outside the USA) you can receive our quarterly newsletter, CryoCare Report, featuring news, opinion, and technical developments related to the practice of cryonics.

If you decide to sign up with CryoCare, full membership costs $350 per year, or $250 for each additional family member. Student memberships are $175 per year, and memberships for children under 15 are $125. These annual dues cover our administrative expenses and help to maintain emergency response capabilities.

We charge a one-time-only sign-up fee. This helps to pay for the large amounts of time that we are likely to spend answering your questions about cryonics, offering advice, and guiding you through the legalities of the paperwork. The fee is $200 for the first non-student, adult member of a family, $150 for each additional non-student adult family member, $100 for full-time students, and $50 for children.

In addition to cryonics membership, you will need to pay for your eventual standby, transport, perfusion, and long- term maintenance in liquid nitrogen. You must make arrangements for these expenses in advance. The most popular way of doing this is to buy a life insurance policy that will pay its benefits to CryoCare after your legal death. For most people in good health and under forty, life insurance is quite cheap. People over forty may still find that it is affordable depending on pre-existing medical conditions. We strongly recommend a policy with a benefit that is indexed to inflation.

How does this all add up? Every person is different, but a CryoCare member aged around 35 who opts for neuropreservation might pay slightly less than $2.50 per day, total, for membership dues and insurance premiums combined. Of course, this does not guarantee a new lease on life, because we can't predict the future. But still it seems a small sum to pay for a chance at rejuvenation and longevity in a world of exciting new possibilities.

If you prefer not to use life insurance and you choose to set aside cash in advance, the minimum funding for standby, transport, perfusion, and maintenance in liquid nitrogen is $58,500 for neuropreservation and $125,000 for whole-body cryopreservation, using CryoSpan as the long-term care provider.

We hope that future growth in cryonics will result in economics of scale that may reduce some of these costs. Obviously we can't guarantee this, and all the figures above are subject to change.

Common Questions

Science Questions

Doesn't freezing burst cells, like water freezing in a bottle?

No. Slow cooling causes ice to form in the tiny spaces outside cells first. This causes an increased concentration of salts outside cells, which draws water out of cells, dehydrating them. At the end of freezing, the space between cells is filled with ice crystals, but cells themselves remain unfrozen (vitreous) in their interior. Ice crystals outside cells still cause damage, but not as much damage as would be caused by ice inside cells.

Has anyone been revived after being frozen?

No. Humans cannot be revived with today's technology. The purpose of cryonics is to carry people to future technology that will be able to revive and treat them.

If no one has been revived yet, isn't cryonics unproven and unscientific?

Cryonics is unproven, but it is not unscientific. Cryonics depends on foreseeable medical advances, not blind faith in the future. In 1961, when the United States committed itself to landing a person on the moon, there was no proof this could be done. Nevertheless scientists concluded from known principles that it was possible. The space program, human genome project, and freezing the DNA of endangered species for future cloning are all projects that were begun based on the expectation of foreseeable technologies that did not yet exist. Like cryonics, they are scientific undertakings, not acts of faith.

Won't memories be lost if a brain stops working, like turning off a computer?

Neuroscientists agree that long-term memory is stored by durable structural and molecular changes within the brain, not transient electrical activity. In fact there are many situations in clinical medicine today in which a patient's brain is stopped and restarted with no lasting harm. These situations include ischemia (stopped blood circulation), deep hypothermia, and deep anesthesia.

Isn't freezing after legal death too late?

In many cases it is possible to have a cryonics transport team standing by during the final stages of a terminal illness. CPR and administration of stabilizing medications can begin within a minute or two after breathing and heartbeat stop (legal death). Under such favorable circumstances, brain injury can be so minor that there would be no difference even if cryonics procedures were begun before legal death.

It is also possible that cryonics may still work even if legal death occurred many minutes (perhaps even hours) earlier. There are published reports in the scientific literature of viable brain cells sometimes being found hours after legal death. Some so-called "dead" patients today may in fact still be treatable by far future medicine. (From a cryonics standpoint, the chief problem caused by protracted clinical death is failure of the brain's circulatory system. This prevents good cryoprotective perfusion, greatly worsening freezing injury.)

Does this mean that future medicine might be able to bring back the dead? Not at all. If patients in the future can be recovered after hours of clinical death, it will simply mean that medicine today is wrong about when it thinks death really happens. When considering these questions it is helpful to remember that death is usually a process, not an event.

The most difficult cryonics scenarios are those involving chronic degenerative brain diseases (such as Alzheimers), or protracted respirator support of severely brain injured patients. By the time legal death is declared in such cases, loss of brain structure can be so extensive that these patients are dead by any medical criteria, present or future. To counter these possibilities, CryoCare recommends that individuals take legal steps (such signing a Durable Power of Attorney for Health Care) to ensure that medical measures such as life support are never utilized in a manner that violates their wishes for timely cryopreservation.

Is research being done? What improvements can be expected?

At the time of writing, privately-funded cryonics research projects are being pursued by 21st Century Medicine and BioPreservation in California, the Alcor Life Extension Foundation in Arizona, and the Cryonics Institute in Michigan. These initiatives are directly aimed at better understanding and improving cryopreservation of the human brain.

Unfortunately no government agencies or other conventional funding sources have an interest in brain cryopreservation. There is, however, some wider interest in cryopreservation of the kidney, heart, liver, and other transplantable organs. In recent years great strides have been made toward reversible cryopreservation of the kidney. The most promising approach is called vitrification.

Vitrification is cryopreservation that takes place without allowing ice crystals to form. We hope that vitrification will be used to achieve reversible (non- injurious) preservation of the human brain within the next decade. If successful, this technology would be perhaps the most important medical breakthrough of our time--an assured means to transport the most essential part of ourselves to any point in the future.

Social Questions

Why would I want to live beyond my natural lifespan?

"Natural lifespan" is a relative term. Today we consider a natural lifespan to be about 75 years because this is how long the average person lives in the industrialized world. Someone from the Middle Ages (with a life expectancy of 30 years) would regard today's medicines and lifespans as extremely unnatural. A century from now, people will probably look back on the lifespans of the 20th century with amazement and even pity as they look forward to centuries of life, health, and youth.

Why should people of the future revive cryonics patients?

Cryonics patients are not being cast adrift upon a sea until some future historian finds them. They are being cared for continuously by an organization (such as the CryoCare Foundation) with the express purpose of reviving them. If a patient stays frozen long enough for revival technology to be developed, it will be because they are still in the care of an organization that intends to revive them. In other words, revival will happen (if it happens) because someone cared enough about your revival to keep you frozen. It will not really matter what the rest of future society thinks.

By the time it is possible to revive today's patients, future medicine will already have a long tradition of treating patients in "suspended animation" and other forms of biostasis. Today's cryonics patients would be morally equivalent to any other injured patient who needs help in that era, and will likely be regarded as such.

We also expect that nanotechnology will follow a declining cost curve, just like the microchip. The first nanomachines will be extremely expensive, as development companies seek to recover the capital they spent on years of research. But nanomachines will have the capability to build more nanomachines. Ultimately, we believe that they will be as plentiful and cheap as transistors are today. As a result, resuscitating cryonics patients may become quite affordable.

When will cryonics patients be revived?

Cryonics will probably be a last-in-first-out process. Patients preserved with the most advanced technology are likely to require the least treatment. At some point, perhaps 50 years from now, completely reversible "suspended animation" will likely be developed, and freezing damage will no longer be a problem. Patients maintained with this technology will not need to wait until science can find a way to repair their individual cells. They can be revived as soon as a cure is available for the injury or illness that stopped their life processes.

Patients frozen before this future time will have to wait for revival. The older the technology used, the longer the wait will be. Someone who is frozen tomorrow may have to wait 100 or even 200 years for repair and resuscitation.

What will the future be like?

If you are maintained properly in the frozen state, and if technology is capable of reviving you, you can bet that human progress continued and civilization did not collapse. In other words, if you open your eyes to a new world, it will almost certainly be a world of wonders. On the other hand, if humanity suffers a disaster, you're unlikely to know about it.

Since we believe that resuscitation will require advanced nanotechnology, the future that you experience will have been transformed by nanomachines. Among other things, this implies:

Ethical Questions

Doesn't cryonics contribute to overpopulation?

Currently about three children are born for every one person who dies. Rushing people off to an early grave is not going to solve this problem; the only answer is to reduce birth rates. This has already happened in the industrialized world, where population is not the problem that it used to be. If past trends continue, birth rates will eventually drop in poorer nations as they too become more industrialized.

Vast increases in longevity will entail substantial changes in the way people think about life and choose to live. By comparison, the resuscitation of cryonics patients will have a negligible impact.

Isn't cryonics an expensive extravagance?

Cryonics often costs less than "heroic" medical techniques that are currently used to prolong life by just a few months. Since cryonics promises to prolong life by decades or possibly centuries, it seems a very prudent use of resources by comparison.

Some people may feel concerned about buying life insurance to benefit themselves instead of their families. In this case, the answer may be to include family members in your cryonics arrangements.

What happens to the soul of a frozen person?

We have mentioned cases where a person drowns in cold water and shows no signs of life for two or three hours, yet is resuscitated and seems no different from before. What happens to the soul in these cases? And what happens to the soul of an embryo that is frozen in liquid nitrogen for months or years, and is then implanted in a womb and allowed to develop normally?

Someone with religious faith might conclude that the soul is dormant, or asleep in God's care, during these periods of seeming lifelessness.

Revival of frozen embryos is not resurrection, and neither is cryonics. If cryonics works it will simply mean that cryonics patients were never really dead but were, instead, in a kind of coma that today's primitive medicine was unable to treat. Medical definitions of death have changed several times this century. These definitions are bound to change even more during the next century.

Does cryonics conflict with religious beliefs?

Medical advances that increase the quality and length of our lives are usually embraced by most religions. If life in this world has a purpose and value, then acting to preserve it by reasonable means is morally valid. Is cryonics a reasonable means? This is a question we must each answer for ourselves.

Acceptance of new medical ideas is sometimes slow. There was once a time when many people considered surgery (or even anesthesia during surgery) to be unreasonable and against God's will. Today we take painless surgery for granted. Cryonics may also require a long time to achieve wide public acceptance. In the meantime we must strive to evaluate cryonics according to its own merits.

Further Reading

Non-Technical Books

Engines of Creation (Anchor Press, 1986) by K. Eric Drexler (highly recommended)

Unbounding the Future (Morrow, 1991) by K. Eric Drexler with Gail Pergamit

Technical Books

Nanosystems (Wiley & Sons, 1992) by K. Eric Drexler, Ph.D.

Published Papers

Drexler K E, Molecular Engineering: An Approach to the Development of General Capabilities for Molecular Manipulation PNAS (USA), 78: 5275-5278 (1981)

Merkle R C, The Technical Feasibility of Cryonics Medical Hypotheses, 39: 6-16 (1992)

How to Contact CryoCare

     Call toll-free for information:
     1-800-TOP-CARE (1-800-867-2273)

     For inquiries via U.S. Mail:
     CryoCare Foundation
     1013 Centre Road
     Suite 301
     Wilmington, DE 19805-1297


     Web page:  http://www.cryocare.org/