X-Message-Number: 9490 From: Ettinger <> Date: Wed, 15 Apr 1998 10:18:27 EDT Subject: Pietrzak's Errors PIETRZAK'S ERRORS John Pietrzak (Cryonet #9489) makes fundamental errors and badly mischaracterizes my approach to probability theory, even though he has made a valiant effort to understand my essay, "Cryonics: The Probability of Rescue." He ends by saying, "Unless I've missed my mark completely, this twenty page thesis comes just about as close to circular reasoning in its conclusion as I've ever seen." Well, he has indeed missed the mark, and there is nothing in the least circular about the reasoning. Aside from advising him to read it again, more carefully, perhaps I can jog him (and any similar others) a bit as follows. The essence of his error is in the sentences, "He's essentially trying to give a large probability to the success of intuition…" and "…we now use our intuitive knowledge of cryonics and apply it (a priori) to a probability function which has…no samples at all!" That last is the exact opposite of the implicit and explicit thrust of the essay. There MUST be samples (prior experience) on which to base any estimate of probability. His confusion arises from the fact that intuition is often correct, although imprecise, because (unconsciously) it DOES rely on experience, on recollection of prior observations. For EXPLICIT application of the method, one DOES compile statistics; but often the thrust of experience is so obvious that compiling statistics would be a waste of time. (For example, we don't run in front of oncoming cars when they are close and moving rapidly, because our remembered experience suggests that this would be a bad idea. We could, if pressed, PROVE this is a bad idea by compiling statistics, but it is so obvious that we don't need numbers on paper.) John quotes from my summary, in part: "In the modern era, not a single goal of science, so far as I know, has been shown to be impossible…." Perhaps I should have added another long section to include a statistical summary, but it hardly seemed necessary. Maybe someone else would like to play with that. Incidentally, John mentions my technical example (the exponential life parameter, which has passed muster with experts in statistics), but fails to see that it is closely related to the summary as applied to cryonics. If he still can't see that, after trying again, I can only shrug and hope others will do better. Robert Ettinger Cryonics Institute Immortalist Society http://www.cryonics.org Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=9490