X-Message-Number: 3199 From: Ralph Merkle <> Subject: SCI.CRYONICS: "How and Why We Age" by Leonard Hayflick Date: Sun, 2 Oct 1994 09:11:42 PDT Hayflick's recent book: "How and Why We Age" (Ballantine, 1994) has a one-and-a-half page section that directly addresses cryonics. This is unheard of. The fact that the caliber of the discussion is terrible is secondary. To date, any discussion of cryonics in the standard literature has been taboo (for example, the Society for Cryobiology has bylaws that call for the expulsion of members who engage in or promote cryonics -- this and other actions have had a significant chilling effect on open discussion). In fact, any discussion outside of the cryonics literature has been rare. The only systematic assessment of cryonics published in the standard medical literature has been by an outsider ("The Technical Feasibility of Cryonics," by Ralph C. Merkle, Medical Hypotheses Vol. 39, 1992, pages 6-16. See URL: ftp://parcftp.xerox.com/pub/merkle/techFeas.html). Ending this "omerta" is all for the good. The fact that Hayflick argues that cryonics won't work, and that his arguments display complete ignorance of even the basics of cryonics, and that he thinks extending human life span is a bad idea; will not come as a surprise to anyone familiar with this area. In the future, we can expect others to include (either in their books or articles) sections on cryonics. As this discussion enters the standard scientific literature, the complete bankruptcy of the arguments against cryonics will become apparent. In the process of writing "The Technical Feasibility of Cryonics" I sought review from a variety of sources (and in particular from individuals who had some claim to expertise and were known to oppose cryonics). The arguments advanced for believing that cryonics would not work were truly and amazingly bad (often worse than Hayflick's, if that be possible). For those interested in Hayflick's argument, here is the one paragraph where he purports to advance reasons that cryonics won't work: "There are several flaws in this procedure. As discussed earlier, animal tissue cannot be viably preserved in a frozen state unless a cryoprotective agent penetrates all of the cells. Whole, live animals that tolerate freezing are able to distribute this antifreeze through a functioning circulatory system. Without a functioning circulatory system the cryoprotective agent cannot penetrate into all cells. In the laboratory, this limits the amount of tissue that can be frozen and thawed with most cells surviving to scraps no bigger than a matchstick head. Furthermore, the thousands of different types of cells in the body probably require different rates of freezing and thawing to maintain their viability. Thus freezing and thawing a whole body or head at a single rate (as is done) would probably not permit the survival of most cell types. Finally, when even tiny portions of animal brains are frozen and then thawed using the methods of cryonicists, considerable cell destruction can be seen." Most remarkably, Hayflick argues that cryonics won't work because it is necessary to deliver cryoprotectants through the circulatory system. Obviously, he is ignorant of the suspension protocols commonly employed (and discussed extensively in the cryonics literature) which go to great lengths to insure that the circulatory system remains intact precisely so that cryoprotectants can be circulated to the tissues. An embarrassed retraction by Hayflick would be appropriate. Second, Hayflick states that cells don't "survive." Unfortunately, he is obviously referring to functional survival by current criteria, an objective whose relevance to cryonics is at best marginal (confer "information theoretic survival," discussed in several places in the cryonics literature). This is probably the single most significant conceptual failure on the part of critics of cryonics. Third, Hayflick refers to "freezing and thawing." Unfortunately, the concept that future technologies must necessarily thaw the tissue is without basis. I would expect, in fact, that analysis (at least) and repair (quite possibly) would both take place while the tissue remained frozen. This is a non-trivial observation, as it eliminates all tissue damage caused by the thawing process. Further, the freezing process is likely to "lock in" the damage. This is best exemplified by fracture damage. Fracturing of the tissue at low temperatures appears likely with current methods. Such fractures, however, seem unlikely to result in information loss. The two faces of the fracture will be complementary to each other, and the relationship of the various cellular components should be quite obvious. If thawed, the opposing surfaces would lose their structure. The relationship between components on opposing faces would tend to be obscured, and further diffusion through what amounts to a cut in the tissue would occur. Obviously, thawing of such a fracture is a bad idea. If analysis is performed on the tissue when it is frozen, such thawing damage is completely avoided. The concept that analysis might take place while the tissue remains frozen has not been considered by most critics. Finally, Hayflick argues that "using the methods of cryonicists, considerable cell destruction can be seen." Obviously, Hayflick has an embarrassing lack of knowledge of the "...methods of cryonicists..." as noted earlier. It is indeed the case that current suspension methods do cause damage, and that the damage is sufficient to prevent the tissue from spontaneously recovering full function (though partial recovery of function is typical). The success at freezing and thawing several types of tissues using current methods implies that the process of freezing is not one of total destruction, even from a functional point of view. Loss of function, however, should not be equated with loss of information. A nerve cell could be quite non-functional yet the path of the nerve cell and the connections it makes with other nerves could be readily inferred given sufficiently detailed knowledge of its physical structure. The emotional bias of most critics of cryonics is usually readily apparent. Hayflick spends considerable time trying to persuade us that slowing or halting aging would be bad (an interesting stance for someone who has devoted his life to the study of aging...) Hayflick is obviously worried that these efforts will succeed. He advances some concerns that he feels raise serious questions: "You stop the aging process at age forty-five, but your older brother or sister chose thirty-five and your parents chose twenty-five. Your children may choose other ages or choose not to arrest their aging process at all. How will you relate to parents who are younger than you, children who are older than you, or siblings aging at a different rate? There are other, equally grotesque scenarios." For all his naivete, Hayflick has, I think, performed an essential service: he is openly discussing the feasibility of cryonics. Regardless of whether you support or oppose cryonics, whether you think it will or won't work, open discussion of its technical feasibility in the standard literature benefits everyone. Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=3199