Re: Is cryopreservation a solution?

Geoff Smith (
Tue, 9 Sep 1997 20:50:53 -0700 (PDT)

On Thu, 11 Sep 1997, Joao Pedro wrote:

> Let's suppose that I die (not that I'm counting on it!) and endure
> cryopreservation.
> The damage done to the cells (or to the neurons which is what really
> matters) during the freezing process is noticeable, many will be
> destroyed in the process not to mention the cells that will be damaged
> while I'm not frizzed. If I'm old, I have already lost many
> neurons and many others would have severe damage.

Certain frogs are have evolved to survive the freezing process, and do so
on a regular basis. If I remember correctly,(I'm sure a zoologist can
correct me here) the frogs release a chemical that dehydrates the cell, or
atleast convert the H2O to another form. This stops massive ice
crystals from forming which lyse the cell.
Surely we can do something similar for human beings?
As for your second point, cryopreservation does just that: it preserves.
Of course you'll come back with lost and damaged neurons, because you had
them when you were frozen. I think one who wishes to be cryosuspended
should weigh two risks: the risk of losing neurons to old age and the risk
that current cryopreservation techniques will cause you to lose neurons.
Unfortunately, I'd say chance has a bigger role than logic in this
decision. Who knows if cryonics works until someone is unfrozen? And who
knows if you will be brain damaged tomorrow? But then, survival has
always been a combination of skill and luck.

> 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.

If I were to extrapolate current technological progress, I would say 100
years is a very conservative estimate. The Prometheus Project's goal is
much less.
And how do you know how much damage is caused by letting frozen
bodies sit for extended periods of time? What is your evidence that
this damage occurs at all?

> In the future, some guys unfreeze my head, probably put it on a new body
> and start
> working on putting me back to life. The answer would be nanotechnology
> to repair the
> damage in my brain cells.
> 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.
> What do you think of this?
> Personally, I'm 19 years old. So, statistically speaking, I have more
> than 50 years to find a cure for aging.

Me too! I've always wondered what the age distribution is like on this
list. From what I've gathered, it appears to range from undergrad
students to around 60 years old. Is that about right? Danny appears to
be younger as well.

> 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?

I would say different matter, different position, same person- at that
point. But after that point, they diverge and become different people.
But that is only if you define a person by their material composition and
history of actions. I'm not sure how else you might define a person, any

Actually, by my definition, the person at location B is NOT the same
person, since s/he does not have the same history of actions, or any
history in fact. So... no, they are not the same person by my definition
of person. If your definition of person is simply material composition,
then they are the same person... but I'm not sure this is an adequate
definition. To illustrate, think of a prize you have won. Now, do you
think an exact atom-by-atom duplicate of yourself deserves this prize or
you. Remember, there is only one prize and no sharing.

> Complicating the situation, I could say that some atoms would not be
> exactly in the same position but the health of the person would not be
> affected. Now, is this the same person who left location A?

No, again.

> What about if some atoms are replaced but the positions remain the same?
> What if some atoms are replaced and some positions changed? What if all
> atoms are changed but the positions are the same? Remember that for
> everyone else this person is always the same no matter how many atoms
> you replace. I'm atheist so I don't believe much in souls but I think
> some of this questions are interesting.

No, no, and no.

I agree, the questions are interesting.
I think the most interesting question of all is: WHAT DEFINES A PERSON?