Re: Is cryopreservation a solution?

Anders Sandberg (
10 Sep 1997 10:28:55 +0200

Joao Pedro <> writes:

> My question is simple, is really cryopreservation an answer to achieve
> immortality?

No. It can only give you a second chance at that.

> The bigger amount of damage would come from the time I would be in
> cryopreservation. I don't have a clue to how much would that be but
> we're talking about 50, 100, 200, 500 years! Even more damage is done to
> the cells.

Actually, this is likely much less damage than the cryopreservation
process (unless your body is mishandled a lot). Chemical reactions does
for all practical purposes not occur at liquid nitrogen temperatures,
and cosmic radiation damage is not a problem for storage less than
a millennium. See

> Here's my problem, they won't know how the cells were when I died, so
> they will just follow a blueprint of 'standard brains' to repair me. My
> problem is that, depending on the extent of the damage, I will no longer
> be me! I will be a different person because my brain will be changed. I
> (or my other me, since that person will no longer be me) might have some
> memories of how I used to be but I will be another person.

I think Fred Chamberlain explained it nicely in his talk at Extro3:
identity is a continuum, not binary. So you can be more or less
yourself, the big question is how much cryonics change that. Our
brains constantly change, so if the cryonics-induced change is on
the same order as normal change (or even the major changes brought
about by (say) non-lethal accidents) it could be said to work -
after all, you usually regard yourself as the same person even
after a period of coma and a few broken bones.

If I was writing the code for the cell repair nanites (for the sake
of humanity, let's hope it will not happen :-), I would probably divide
damage into three classes:

Simple damage, such as denaturated proteins, cross-links, ruptured
cell membranes and microcracks. This kind can be dealt with fairly
easily by just fixing it, there is an obvious correct solution (OK,
finding that solution might be hard).

Major cell damage: cells that have been destroyed altogether. I don't
think anybody would object to replacing non-nerve cells with 'standard
cells' based on your own cells (why use anybody else's?). Replacing
neurons is problematic, but if we have a good idea we could always
put in a neuron of the most likely type and connect it to the synapses
we know of; not good at all, but as long as they are fairly few the
change in identity will be very minor.

Big damage: parts of the body where no information is left; we just
have some hints in the debris left. Here we have to use all the
available knowledge to create a plausible replacement, hoping it
will not be too far off.

Obviously, if cryonics produces a lot of big damage then it is
likely that the revived "you" would not be much like you. But given
better suspension methods, the first two categories would become more
common, and they do not decrease your identity as much. Ideally
we would only have simple damage, but in real life there will
be some neural major damage (hard to avoid).

> This reminds me of an interesting problem I once argued about, let's
> suppose that scientists find a way to transpose a person to another
> distant place, almost instantly.
> Of course that one's molecules would have to be disorganized and a mass
> of one's molecules would be formed. This mass would then go to the other
> place in a few seconds and the molecules would, again, be arranged so
> that the body of the person would be a body again, a super computer
> would know the exact positions of each atom so that the person who left
> location A would be exactly in the same conditions is location B.
> Do you think this is the same person who left or is another?

Now we are getting into the identity question. Most people have different
answers, but a large number of transhumanists seem to be in the pattern-
identity camp: it is the pattern of atoms which makes us us, not which
atoms. So if you could replicate the pattern you would replicate me.

Anders Sandberg                                      Towards Ascension!                  
GCS/M/S/O d++ -p+ c++++ !l u+ e++ m++ s+/+ n--- h+/* f+ g+ w++ t+ r+ !y