Cryonics is the study and practice of keeping a newly dead body at an extremely low temperature with the purpose of preserving and hopefully restoring it to life at some future date; perhaps decades or even centuries later (Alcor Life Extension Foundation, 1993, p. 60). The potential success of cryonic suspension relies heavily on continued advances in medical technology, especially nanotechnology, to not only treat the original cause of death, but also to repair the cell damage caused by freezing the body. For this and other reasons, cryonics has provoked a lot of controversy. Many people believe strongly in it, while others think it will never be successful. In the end, people who choose cryonics, as a way of extending life, have nothing to lose and potentially immortality to gain.
While the practice of cryonics has only been around for about 50 years, the idea of preserving a human body after death, and later reviving it, has been around for hundreds of years. In a letter dated April 1773, Benjamin Franklin wrote: I wish it were possible to invent a method of embalming drowned persons, in such a manner that they might be recalled to life at any period, however distant; for having a very ardent desire to see and observe the state of America a hundred years hence, I should prefer to an ordinary death, being immersed with a few friends in a cask of Madeira wine, until that time, then to be recalled to life by the solar warmth of my dear country! But in all probability, we live in a century too little advanced, and too near the infancy of science, to see such an art brought in our time to its perfection (Franklin, 1956, p. 29).
The idea of preserving and later reanimating a dead body continued to evolve in popular literature. There are many examples, including Jack London's "A Thousand Deaths" (1899), in which the hero is intentionally frozen in order to be resuscitated, three months later (London, 1899, pp.