07 May 2007

A Few Reasons Too Many

"For the most part" (hôs epi to polu) --either a fudge, or an indispensable apparatus of philosophical elegance. Shall I say, then, that this blog deals with ancient philosophy "for the most part"?--since clearly that is true.

And then, if the link with classical sources seemed too tenuous, I would be dispensed from having to give further explanation for why I would wish to post on a fascinating review by Alexander Pruss of a book by Graham Oppy.

Among many arguments in the review that caught my attention, perhaps it was the following that most intrigued me (especially the highlighted sentence):

However, it is not rational to assign to theism a credence interval containing zero, unless one actually has a valid deductive argument for the non-existence of God from indisputable empirical observations and/or from self-evident truths, and Oppy has not given us any evidence to think he has such an argument. For let E be the following event: the skies brighten, everyone's computer screen flashes the words "I am God: listen to my revelation" in colors beyond the chromatic range of one's monitor, each mathematician finds a gold-edged piece of paper (the gold turns out to have no impurities at all and no impurities can be introduced) with a correct solution to a difficult open problem, signed "God", every turned-on Geiger counter has a gold-edged piece of paper on it listing, in very small print and with 20 digit precision, the exact time of every click over the next 48 hours, signed "God", all those with any physical ailments or abnormalities find these ailments and abnormalities gone, and instead find themselves holding a gold-edged piece of paper saying: "I wish I could have done this earlier, but I could not reasonably do so due to reasons you would not understand -- God". Barring a deductive argument against the existence of God from indisputable premises, the occurrence of E should rationally make one believe in God. But if one initially assigns a credence interval containing zero to the existence of God, then (this is a theorem) no evidence whose probability is greater than zero on the no-God hypothesis can in a Bayesian way raise the credence to an interval that does not contain zero. But the probability of E is greater than zero given indeterministic quantum physics -- E could occur out of purely naturalistic causes. Hence, assigning a credence interval containing zero to the existence of God is irrational as it makes it impossible to respond as one rationally ought to possible evidence such as E.
Pruss' argument against Oppy's way of modelling 'credence' with a probability range seems to me ingenious.

Yet as regards Pruss' particular choice of E, I am ready to side with the existentialists and wonder:

1. Suppose E really did happen, then, whether you are an atheist, agnostic, or theist--would you thereby have any more reason to believe that God exists than you have already?
2. Suppose you think that, if God existed, he would not be the sort of being who would try to make others believe that he existed: then how would you interpret this evidence?
3. Does the explanation "I wish I could have done this earlier, but I could not reasonably do so due to reasons you would not understand -- God", seem especially godlike to you (compare: the book of Job). Or doesn't it rather seem, well, foolish?
4. What if very pure silver were used around the edges of the paper, instead of gold?

2 comments:

Leon said...

I'm reminded of St. Anselm's proof, that even if valid, can convince one only of a sort of thing that isn't quite commanding as God, but just as something 'greater' - maybe even omniscient and gold-dispensing - not as a God that will ultimately order everything according to some sublime justice. For what could prove that but something really severe and revolutionary like the Second Coming? Your humorous comments do well to draw attention to the huge acculturated load which 'God' carries, and by means of which alone, I think, any such arguments can gain cogency.

Michael Pakaluk said...

Leon,

I would add that, if E as described did occur, then God would apparently have given us the sure resolution, too, of a nice dispute in English usage, viz. over the phrase "due to".

See for instance this entry from the American Heritage Book of English Usage.

due to
"Due to has been widely used for many years as a compound preposition like owing to, but some critics have insisted that due should be used only as an adjective. According to this view, it is incorrect to say The concert was canceled due to the rain but acceptable to say The cancellation of the concert was due to the rain, where due continues to function as an adjective modifying cancellation. This seems a fine point, however, and since due to is widely used and understood, there seems little reason to avoid using it as a preposition."