دانلود کتاب The Prospect of Immortality

Beginning in 1962, Robert Ettinger initiated the practice of cryonics, the discipline of cryopreserving humans at the time of medico-legal "death" in anticipation of rescue and recovery in the future by potentially more advanced medical science with his book, THE PROSPECT OF IMMORTALITY. Ettinger argued that the contemporary criteria for pronouncing death are exclusively function-based and thus dependent upon the sophistication, or lack thereof, of the medicine available to treat5 the patient. He argued that the brain is a discrete pattern of atoms, each as effective as the next as long as the unique pattern of their arrangement persists. Presumably all of the attributes of personhood are encoded in this lattice. This view allows us to view the person as ‘information beings’, defined by the arrangement of particular atoms that comprise our brains at any moment. So long as that pattern of information can be recovered, the person is not dead. If a cookbook is ripped to pieces it is no longer functional; it is impossible to read or use. The torn pages still contain all the information required, however, to allow for the book to be pieced back together and restored to a functional, useful state. By contrast, if the book is burned and the ashes stirred, the loss is irreversible given our current understanding of physical law (the limitations imposed by both the laws of thermodynamics and information theory).

This approach to defining death, which is rooted not in relative, changing technology and vitalistic worldviews, but rather in the fundamentals of physical law, is known as the information theoretic criterion of death as stated by Ralph Merkle, the computer scientist who is one of the inventors of public key cryptography and the inventor of cryptographic hashing: “A person is dead according to the information
theoretic criterion if their memories, personality, hopes, dreams, etc. have been destroyed in the
information theoretic sense. That is if the structures in the brain that encode memory and personality have been so disrupted that it is no longer possible in principle to restore them to an appropriate functional state then the person is dead. If the structures that encode memory and personality are sufficiently intact that inference of the memory and personality are feasible in principle, and therefore restoration to an
appropriate functional state is likewise feasible in principle, then the person is not dead.”

The utility of the information-theoretic criterion of death to contemporary medical practice is to point out that few if any patients pronounced dead by today’s physicians are in fact truly dead by any
scientifically rigorous criteria. This is the subject of THE PROSPECT OF IMMORTALITY from the perspective of 1964 when Ettinger first promulgated the idea of medical time travel for the delayed rescue of today's dying and newly "dead" patients