re bayesian statistics theism and atheism in article apr dcs warwick ac uk simon dcs warwick ac uk simon clippingdale writes in article quei mb horus ap mchp sni de frank d s uucp frank o dwyer writes in article apr dcs warwick ac uk simon dcs warwick ac uk simon clippingdale writes i write imagine that alterian dollars turn up in your bank account every month suppose further that this money is being paid to you by a your big hearted alterian benefactor or b a bug in an alterian atm let s suppose that this is a true dichotomy so p a p b trouble is alterius is in a different universe so that no observations of alterius are possible except for the banks you couldn t possibly afford it now let s examine the case for a there is no evidence whatsoever that there is any such thing as a big hearted alterian benefactor however p exists b h a b p not exists b h a b on the grounds that lack of evidence for is evidence against when we have a partition like that we dismiss hypothesis a turning therefore to b we also find no evidence to support that hypothesis on the same grounds as before we dismiss hypothesis b the problem with this is that we have dismissed all of the possible hypotheses and even though we know by construction that the money arrives every month we have proven that it can t because we have dismissed all of its potential causes that s an extremely poor argument and here s why premise this money is being paid to you by either a your big hearted alterian benefactor or b a bug in an alterian atm thus each monthly appearance of the bucks should it happen is an observation on alterius and by construction is evidence for the existence of either the benefactor or the bug in the atm premise no observations on alterius are possible except for the banks you couldn t possibly afford it you forgot to include this my premise is actually premise the cardinality of the set of possible observations on alterius is one this is clearly contradictory to the first not if you state it properly trouble is on the basis of premise you say that there can be no evidence of either the benefactor or the bug but the first premise leads to the conclusion that the appearance of the bucks should it happen is evidence for the existence of either the benefactor or the bug voila a screaming contradiction with my highlights sc but in a strawman argument there is only evidence for oneof benefactor bug no observation to distinguish benefactor from bug is possible that is not evidence for bug and neither is it evidence for benefactor nor is true to say that this hypothetical universe appears exactly as if there were no benefactor bug two statements both would be false this is still contradictory it reduces to alterian dosh arriving in my account is due to benefactor or bug this is not evidence for benefactor neither is it evidence for bug meaning that it doesn t lend more weight to one than to the other therefore no evidence can exist for benefactor and no evidence can exist for bug but relies on a shift in meaning from when you say paraphrased in that this is not evidence for benefactor for example what you mean is that it s no more evidence for benefactor than it is for bug yes that s what i mean in however you ve shifted the meaning of evidence for benefactor so that it now means absolute evidence for benefactor rather than relative evidence for benefactor w r t bug not really i meant evidence that would tend to one over the other i think this is just a communications problem what i am trying to say in my clumsy way is that while i buy your theory as far as it relates to theism making predictions prayer your rapture example i don t buy your use of occam s razor in all cases where a in my example one couldn t dismiss benefactor or bug on the grounds of simplicity one of these is necessary to explain the dosh i brought up the one by one dismissal process to show that it would be wrong to do so from what you re saying in this post it seems you agree and we re talking at cross purposes is still in contradiction to some sums may help with b benefactor b bug d dosh arrives in account implies p b b d assuming that p bb d so it s either the benefactor or a bug which is responsible if the bucks arrive but not both then p b b d p b d p b d so p b d p b d but implies that p b d and p b d no this isn t what i meant p b d and p b d with necessarily no new observation we ve already seen the dosh to change those estimates i was trying to say again in my clumsy way that it would be wrong to assign probability to either of these and that s precisely what use of the razor does in the case of gods gods are one class of hypothesis there are many others belonging to a set of hypotheses one of which is necessary to explain something which otherwise would not be satisfactorily explained it can be thrown out or retained on grounds of non rational preference not of science or statistics alternatively one could chuck out or retain the lot on the grounds that the answer can t be known or that the notional probability estimates are effectively useless being equal agnosticism weak atheism as they do when the set m is filled by the universe is caused by x where x is gods pink unicorns nothing etc and no observation tends to one conclusion over the other exactly the point i was making i think so we don t throw out any of these contrary to your assertion above that we do some people do simon and they think they are doing excellent science my sole point was that they aren t only observations which directly contradict the hypothesis h i i e x where p x h i can cause p h i to go to zero after a finite number of observations only in this case do we get to throw any of the hypotheses out exactly my point though i may have been unclear you said the diametric opposite which i guess is the source of my confusion i was merely trying to illustrate the incorrectness of doing so what i m trying to say is that while you are correct to say that absence of evidence can sometimes be evidence of absence this does not hold true for all or perhaps any versions of theism and it isn t true that those for which it does not hold can be discarded using the razor on the contrary those for which it does not hold are exactly those which can be discarded using the razor see my post on the other branch of this thread then you seem to be guilty of the contradiction you accuse me of if the razor holds for gods then it holds for all like hypotheses which means that you re assigning p x h i for all i though we ve already established that it s not correct to do so when sum p x h i over all i simply put anyone who claims to have a viable proof of the existence or non existence of gods whether inductive or no is at best mistaken and at worst barking mad luckily i make no such claim and have specifically said as much on numerous occasions you wouldn t be constructing a strawman here would you frank although that doesn t of course rule out my being barking mad in any case i could be barking mad in my spare time with apologies to cleese et al but i think you miss the point once again when i say that something is evidence against an hypothesis that doesn t imply that observation of the said something necessarily falsifies the hypothesis reducing the estimate of p h data to zero if it reduces this quantity it s still evidence against h no i got that i m talking about the case when a you re clearly correct when a and i m not constructing a strawman though it s certainly possible that i ve misunderstood what you re saying however by any standards a system that says when a gods are highly unlikely and when a gods can be dismissed using the razor is a system purporting to be an inductive proof that gods either don t exist or are unnecessary to explain any or all phenomena in my experience systems such as this including those which purport to prove that gods exist always contain a fallacy upon close examination if that s not what you re saying then please put me straight frank o dwyer i m not hatching that odwyer sse ie from hens by evelyn conlon
