Maybe procrastinators are trying to over-estimate it to get themselves to do it...
The probabilities are nuts though. For the whole thing to be of use,
1: you must die in a right way to get frozen soon enough and well enough. (Rather unlikely for a young person, by the way).
2: cryonics must preserve enough data.
3: no event that causes you to lose cooling
4: the revival technology must arise and become cheap enough (before you are unfrozen)
5: someone should dispose of the frozen head by revival rather than by garbage disposal or something even nastier (someone uses frozen heads as expired-copyright data).
Note that it’s the whole combined probability that matters for the decision to sign up. edit: and not just that, but compared to the alternatives—i.e. you can improve your chances by trying harder not to die, and you can use money/time for that instead of cryonics.
edit2: also, just 3 independent-ish components (freezing works, company doesn’t bust, revival available) with high ignorance get you down to 12.5%
You might be interested in reading some other breakdowns of the conditions required for cryonics to work (and their estimates of the relevant probabilities):
Maybe procrastinators are trying to over-estimate it to get themselves to do it...
The probabilities are nuts though. For the whole thing to be of use,
1: you must die in a right way to get frozen soon enough and well enough. (Rather unlikely for a young person, by the way).
2: cryonics must preserve enough data.
3: no event that causes you to lose cooling
4: the revival technology must arise and become cheap enough (before you are unfrozen)
5: someone should dispose of the frozen head by revival rather than by garbage disposal or something even nastier (someone uses frozen heads as expired-copyright data).
Note that it’s the whole combined probability that matters for the decision to sign up. edit: and not just that, but compared to the alternatives—i.e. you can improve your chances by trying harder not to die, and you can use money/time for that instead of cryonics.
edit2: also, just 3 independent-ish components (freezing works, company doesn’t bust, revival available) with high ignorance get you down to 12.5%
You might be interested in reading some other breakdowns of the conditions required for cryonics to work (and their estimates of the relevant probabilities):
Break Cryonics Down (March 2009, at Overcoming Bias)
How Likely Is Cryonics To Work? (September 2011, here at LW)
More Cryonics Probability Estimates (December 2012, also at LW)