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Author
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Topic: PIPR: Principle of Inflated Probabilistic Resources
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Tom Stalnaker
Member
Member # 114
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posted 28. February 2002 19:30
I could be totally wrong on what I said earlier, in which case I would be especially  given that I have diverted the discussion of the board. In that case accept my apologies.
That being said, I still think the second case, in which there is no "selection effect" (I am using that not in any evolutionary way) is somewhat different than the case in which survival means that you won the lottery. For instance, imagine a lottery in which there are 10^19 players, and in which each player does not have any contact with other lottery players, and in which no one tells you if you have won. If, after the lottery is over, you are considering whether you won the lottery but have no independent evidence of that being the case, you should conclude that you probably did not win it. (this is a bit different than my mouse example, but more appropriate, I think)
This kind of lottery is analagous to Dembski's Arthur Rubenstein case, in which we are wondering if Arthur Rubenstein (whom we are listening to) might be a musical imbecile who is very lucky while banging at the keyboard. Just as in the lottery, no one would "tell" us if Rubenstein were a lucky musical imbecile (i.e. we have no independent evidence of it.) Well, suppose we are living in an expansionist universe. Then it is likely that somewhere in the expansionist universe, someone resembling Rubenstein is in fact a lucky musical imbecile. However, it is extremely unlikely to be the case in our little corner of the universe. Thus we are entitled to conclude that Rubenstein is not a lucky musical imbecile. Thus the design inference.
This kind of reasoning is quite different in the case in which all non-winners have already been killed. In that case, our existence gives us a piece of information that we don't have in the other case. This piece of information, as far as I can tell, is valid and can be used to inform our probabilistic assessment. This information is analagous to that of being given 100,000,000 dollars after the lottery has been conducted. In that case, we would be surprised, but we would be in possession of independent information indicating that we in fact won the lottery. (When I say independent information, I mean information independent of our pre-lottery calculation of the probability of winning).
So, the two kinds of cases appear to elicit different post-event analyses. In the case with a selection effect, we are surprised and feel extremely lucky, but still attribute the result to chance, whereas in the case with no selection effect, we strongly doubt whether the small chance event even happened. (it occurs to me that I may be misusing "selection effect" , but I hope you know what I mean. I was trying to imitate Dembski's usage  ).
IP: Logged
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Petri Kivenheimo
Member
Member # 151
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posted 05. March 2002 16:30
(Continuing the discussion about selection effects. Sorry for the time elapsed.)
I checked what Dembski had written about the notion of selection effect in _The Design Inference_ (that is, pages 182 and 188, found from the Index). Now it seems to me that the notion is about a kind of false conclusion based on an initial inability to appropriately focus the question to be assessed. (That's approximately the idea we thought it was, but perhaps not quite, I guess.)
The more precise idea behind the term seems to be a situation, where one wants to explain more than is actually needed. E.g., if I see a nest of ants previously unknown to me, I could want to take a closer look on one of them. Therefore, I would pick one up. Now somebody could ask me, why I picked this specific ant up, although my only idea concerned just the kind of the ants, not any individual ant especially. As any ant from the nest would have fulfilled my curiosity, the fact that this specific one became picked up is in no need of explanation, as the corresponding probability, although small, is unspecified: neither I nor the questioner could tell what would be meaningfully different had I picked some other ant instead.
So, a selection effect concerning life on earth would become something like what follows: Why is it that there is life on planet earth? No need to answer to that, as we are not interested in the specific event of life on earth but in the generic event of life somewhere in the universe. The inflationary version, I guess, goes even further, claiming that neither are we interested in the event of life in this observable universe but in the hyper-generic event of life in the postulated inflationary universe. As we might postulate so vast an inflationary universe that quite anything could be probable enough to happen somewhere in it, there should be no need to answer any question whatsoever any more, except by stating that only ignorant people ask such questions. Viz., anything could happen just by happenstance, so any further investigations would be a waste of time and effort. It would make life kind of easy, were that really the case.
Now, the PIPR is saying that life is not so easy, because we are, in fact, interested in the observable in the pursuit of science. So, the three kinds of explanation — regularity, chance, and design — are to be assessed within the probabilistic resources empirically verifiable. Put this way, the PIPR seems rather indispensable for the ID methodology, at least to me.
Still one more idea. The distinction between a case when we probably did not win in a lottery, as the initial probability of winning was very small, neither got we any information about us having won, and the other, when we got a huge sum on money, is of course a valid example of its kind of situation. The question concerning the design inference seems nevertheless to be a different kind of situation. The lottery question was not about the existence of the lottery but about how we did in it, but the question in the design inference is one of inference to the best explanation, be it a lottery prize or a voluntary donation. If we postulate a lottery in the first place, we are naturally entitled to consider us the winners of it, if we get a huge fortune for free; but what if there was no lottery at all, and the money came from somebody who specifically wanted us to have it? Such things do happen, too, you know.
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