IUBio

Cryonics oversell?

Eugene Leitl Eugene.Leitl at lrz.uni-muenchen.de
Wed Sep 4 05:08:33 EST 1996


On Mon, 2 Sep 1996, john wrote:

> Yes it probably is oversold I believe.
> But since so many items from blood to whole living mammals have been stored for

No large biological system, "whole living mammals" set apart, has ever 
been restored to living condition from cryosuspension, even transiently. 
Period.

According to Suda's (a 1966 "Nature" paper?) _unconfirmed_ experiments, 
glycerolyzed cat brains stored for several months under 
unfavourable conditions regenerated artefacted EEG upon defreezing (_not_ 
vitrification) & reperfusion with feline blood. By today's standards, the 
experiments were crude. If any cryobiologist is reading this, his 
comments upon the original experiment would be highly appreciated.

Freezing nematodes & other hardy microcritters cannot be equaled to 
cryopreservation of large, anisotropic biosystems. The best one can hope 
for, is low-damage reversible vitrification of singe _organs_, e.g. 
kidneys for transplantation medicine. Though there has been some progress 
in this direction, it has not yielded a full success yet.

Cryonics does _not_ say the cryopreserved system to be viable upon 
devitrification sans heavy nanoreconstruction. Should nanotechnology be 
impossible, then cryonics is patently impossible (ignoring here more 
arcane scenarios as uploading, etc.). 

> longer than any accidental apparently dead person has, it must have some 
> probability of working on humans in the future.

We have to assume a nonfinite probability does indeed exist, though no 
reliable estimate is possible, of course. (Only religion offers comfortable 
absolute statements, alas).

> In the realisation time of the incurable cause of death of anyone, this option 
> competes for financial savings in a rational way, though I feel the normal 
> disposal of estates are still more justified.

According to some trivial theories, evolution has artefacted a 
mental reality filter for some events as e.g. propagation and death. This 
hypothetic filter is thought to a) suppress reasoning about own death b) 
by raising strong negative emotions in the face of death or its discussion.
(A tentative corollary of this is the fact that belief in an afterlife 
is the basis of virtually all cults, all over the globe).

In the majority of the populace this hypothetic filter renders all 
rational discourse about death, especially one's own death, impossible. 
The discussee is often subjected to intense hostility, i.e. ad hominem 
reasoning. It would be interesting to test, whether such a filter really 
exists. A psychologist could cook up an experiment to (dis)prove this 
quite easily, obviously.

> Most important of all is it makes people look further to the future in this 
> fast evolving world than anything else.

Well, at least one single positive thing. Liquid nitrogen's cheap. 
Spinoffs for both transplantation and IC medicine (e.g. liquid ventilation 
CPR) & cryobiology are on record. Even if cryonics should prove itself 
inviable, the overall result should be positive. 

What's the problem, then?

> The individual considers pension and then will, but now the posibility of a 
> life time after death.
> Its your money so its your bet for a better world.

Right. Just I ask for is rational discussion. Afraid of a mere taboo? 
Willing to expose obvious kookery?

To avoid alienation of hard scientists, which patience has been sorely 
tried indeed, I propose to move all followup to sci.cryonics. Thanks.


-- Eugene Leitl

P.S. One single thing: does anybody in here do SPM (AFM) of vitrified 
neural tissue in vacuum (freezefract, sublimation etch) under cryogenic 
conditions? Has anybody tried excimer pulses for complementary 
photolytic etch? Results?


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