X-Message-Number: 9549
From: Ettinger <>
Date: Sun, 26 Apr 1998 12:42:14 EDT
Subject: Pietrzak 7

PIETRZAK 7

John Pietrzak (Cryonet # 9546) again gets high marks for thoughtfulness, but
still misses the targets--perhaps the result of lack of sufficient clarity on
my part.

1. Referring to the exponential life parameter example in "Cryonics: The
Probability of Rescue," I had said that moderate values of expected life are
clearly--a priori--more likely than extreme values. He denies that this is
necessarily true, noting that mortality rates for people are higher in extreme
youth and extreme age; and that, in manufactured items, a preponderance of
failures due to manufacturing errors would bias the mean life to the short
end. 

His examples are not relevant. If you were estimating expected life (at birth)
of people in a certain country, say, it wouldn't matter that mortality is
higher in infants and in dotage. It remains true, and obvious, that a moderate
value of life expectancy is much more likely (a priori) than an extreme value.

Of course if (say) an epidemic wiped out most of the infants in some year,
that would reduce life expectancy at birth (as calculated a posteriori) for
that generation. Or if a forced emigration with great hardship wiped out most
of the old people, that would reduce the remaining life expectancy at advanced
ages, as calculated a posteriori. But all this is irrelevant for our purposes.
The only human life expectancy analogous to the exponential life parameter is
that at birth, and I repeat that it is clear and obvious that moderate values
are much more likely beforehand than extreme values.  Similar remarks apply to
the manufacturing situation. 

2. The other main objection he makes is that in my argument we could
substitute any other word for "cryonics" with the same result.

Almost right--but not any other "word;" any other "project of technology."
That is exactly the point, our criterion of similarity. Understanding this on
a visceral level requires considerable reflection, because it conflicts with
our feeling that there is something special about our own particular
experiment or project, which (we tend to feel) might invalidate the criterion.

Go back to the football example. A powerful team faces a weak team, and
everyone familiar with American football knows the weak team has much less
than a 50% chance.  Yet a foreigner, with no time to investigate and no
knowledge of football, would be justified in making a bet at even money
(provided he chose first), since FOR HIM the relevant sequence of experiments
would be tossing a coin. We must battle any lingering feeling that the
foreigner is "wrong." 

From the standpoint of physical law, a good case can be made that almost
everything is impossible--in fact, that the only things possible are those
that actually happen. Everything that is not forbidden is compulsory--Gell-
Mann's totalitarian principle. It is conceivable, for example, that there is
"truly" no such thing as survival of a person over time, even in the ordinary
course of events, and therefore cryonics cannot work. Nevertheless,
probability calculations are extremely useful, even indispensable.

 3. I had said a "failed" project of technology, for our purposes, is one
which not only has not yet succeeded, but has been proven to be almost
certainly unachievable. Mr.Pietrzak thinks this is too vague, and I concede
this. In fact, I am willing to bend over backwards and characterize a project
as "failed" if it has been totally abandoned by serious people (even though it
might have been abandoned undeservedly). 

But please don't forget that "project" refers to ends, not means, and
furthermore to ends that remain valid. A project to build an ornithopter would
not count as abandoned, because the primary end--a flying machine--has been
achieved. Likewise, a project to design a better way to clear city streets of
horse manure would not count as abandoned, because the goal is obsolete.

Eventually--within the next few weeks--I expect to improve the last part of
the probability essay on our web site. If anyone can come up with any projects
of technology that have failed--by my criteria--I will be interested to see
them. 

Robert Ettinger
Cryonics Institute
Immortalist Society
http://www.cryonics.org  

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