From HomoExcelsior

Why live forever?

Humans have dreamed of extending their lifespans or achieving immortality since the dawn of time. In the myths heroes and sages gained or lost it, alchemists sought the elixir of life and prophets promised an immortal afterlife for the faithful. To many the idea of having to die was unbearable, and they sought consolation by inventing explanations that made death necessary, desirable, or even illusory.

Transhumanism is basically life-affirming, and seeks to remove all barriers to human growth and experience. Aging and death are the most immediate hinders for self-transformation and personal freedom, and prevents us from living our lives to the fullest.

Today we are learning more and more about the biological processes of aging, and instead of relying on wishful thinking we can actually study the problem of aging and life in an empirical manner, applying the tools of science and gaining practical benefits. Medicine has already extended our life expectation significantly, and there is good reason to believe this will continue in the future. Not only are we living longer, we are also living healthier and more youthfully.

Extending the human lifespan (the maximal age we can live) is the next step. Currently it seems that only the life expectations are rising, but the eventual goal of life extension is to increase the lifespan too. This may be achieved by understanding and controlling the aging process, for example by control of the telomeres and hormonal clocks or through calorie restriction.

Immortality

Life extension points in the direction of immortality. Immortality can of course never be reached completely, there will always be accidents and unknown dangers. But the goal of immortalism is to make death something very unlikely to happen without conscious design.

To halt or reverse aging we need very advanced medical knowledge and the ability to modify our bodies extensively. This may include genetic engineering, using nanomachines to keep cells vital and safe, artificial replacements for failing organs or even complete transformation.

Immortality requires just as dramatic sociological and mental changes. All human cultures have been implicitly based on the assumption of finite lifespans, and we have to learn both how to deal with very long lives both economically, socially and especially mentally. One important question is how to keep our minds open and dynamic in the long run.

Cryonics

Obviously, the above-mentioned technologies do not exist yet, and may have unforeseen limits. Despite this there is a slim hope for old people or accident victims today: cryonics.

The idea of cryonic suspension is to carefully freeze the body so that it is preserved essentially unchanged, until a future time when medical technology has advanced far enough to enable revival and curing of the ailment forcing the suspension.

The current main problem is how to minimize freezing damage: as the water inside the cells freezes, ice crystals grow and disrupt the tissues. This can be circumvented by adding cryoprotectants, chemicals that prevent the formation of large crystals. Damage to the brain due to lack of oxygen has also to be avoided, but methods to at least partially solve these two problems exist and are being refined.

Compared to the suspension process the storage is fairly simple, just keeping the bodies safe and cooled with liquid nitrogen. The most complex part of cryonics will be the future revival process; the most likely way to achieve this is to use nanotechnology to repair the body from a cellular level and up.

This is of course a big gamble, since it has to deal with unproven technologies, assumptions of future abilities and the preservation of the body. But the patient have nothing to loose and everything to gain from being suspended; even if the chances of being revived are very slim they exist, as opposed to being buried or cremated.

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