Does Pascal's Wager contain any logical flaws or fallacies?
Blaise Pascal's famous wager was that even if the existence of God cannot be determined through reason, a rational person should wager as though God exists, because living life accordingly has everything to gain, and nothing to lose.
What logical flaws and/or fallacies (if any) are committed in making this argument?
I wonder if the question would be a better example for the future if it did not take sides? Perhaps a better (though equivalent in meaning) question would be, "Is Pascal's Wager a valid and compelling argument?"
@Jon added "if any" and changed the phrasing of the question for a bit more neutrality. Good point.
In addition, it might be better to quote Pascal rather than paraphrase. I think your formulation is somewhat inaccurate: the actual Wager is between infinite reward and finite loss. But I suppose this will be common and must be dealt with if and when the site goes public. But I enjoyed the question and enjoyed answering it.
Perhaps one could consider a "co-god" which gives infinite punishment exactly in the cases an original god would give infinite reward, and vice versa. One would then argue that there is as much warrant for the co-god construction as for the existence of the original god in question. The idea is that they would cancel out.
He assumed that if God exists then
1a. humans are immortal (as a necessary condition for 1b)
1b. God decides whether they are tortured eternally or happy eternally (one of them is enough to profit infinitely, though)
1c. God bases his decision on whether they believe in him (if this is not the case, the wager does not work, because believing in God or believing in God because of the wager might cause infinite torture)
1d. God bases his decision on whether they follow religious law (again, the wager does not work if God does not like people following religious law)
1e. God is the Christian God and you have to believe in exactly the right doctrinal points and those are the points that Pascal was raised with (again, the wager does not work if God does not like people to follow a particular religious law)
It is not true that you have nothing to lose if there is no afterlife and you have spent all your life following the instruction of the religion even though you would have preferred to do something else.
He also assumed that he can rationally decide to believe.
Summary: The wager assumes that there is a positive probability for God rewarding a particular behaviour with eternal bliss and a zero probability for God punishing this very behaviour with denial of eternal bliss. There is no reason for this assumption.
If the probability for a reward is in fact zero, it does matter if you sacrifice all the life you have for a non-existing reward.
If the probability for God disliking the behavious is not zero, then you have to weigh more than one infinite expectance values.
Even if everything works fine, you would have to be able to believe or disbelieve just because you want to. (Like, say, an atheist who reads a study that believers have a better healing chance for a particular cancer and decides to become a believer as a therapy.)
It's logically fine if someone believes all the assumptions and then says that it is a good idea to believe. But this person believes in the first place, they do not believe because of the assumptions, they are just happy with their belief because of what they believe.
and I must add that this is one particular view of what God may be like. There have been many Gods in the past, and there is no particular way to think that God is supposed to like what Pascal had in mind.
@Bob Some interpretations of the Wager argue that it could be suggested that believing in a generic God, or a god by the wrong name, is acceptable so long as that conception of God has similar characteristics of the conception of God considered in Pascal's Wager. I think that "many religions" is a valid flaw, as most Gods aren't tolerant of other religions, but I'm sure there are many other flaws :)
@thei This is a good answer, but I think that there is more wrong with the wager than just this. You cover inauthentic belief well, but are there any other logical fallacies in the wager? Perhaps an argument from inconsistent revelations? And are any of the assumptions Pascal made false?
In item 1b, the infinite reward is sufficient. Pascal did not mention eternal torture. 1a and at least 1e are also superfluous. But then all of item 1 is simply an attempt to rephrase the Wager and I don't see how it is a fallacy at all. Item 2 misunderstands the Wager—Pascal concedes the potential loss exists, but that it's finite. Perhaps you are looking for the false dilemma fallacy?
Your 1c and 1d/e are mutually exclusive. 1c is closer to my reading of Pascal, but wouldn't it be better to phrase an answer in purely logical terms?
If I'm not mistaken, I think that Richard Dawkins wrote in "The God Delusion" that the reason that hell is said to be so terrible is to cancel out it's implausibility. On a regular basis, punishments far less terrible than hell deter people from doing bad things, but since the notion of being punished forever after you die seems implausible, the punishment is said to be extremely terrible to make up for this implausibility. I think that it's a great explanation!
Actually the Bible does not say people go to Hell; if they keep denying the Lord Jesus Christ up until they die then they might be judged harshly and sent to the Lake of Fire. Of course you don't have to believe this. Richard Dawkins should have known this. Did you know Richard Dawkin's brother is Catholic (I think).
I gave a down vote (sorry) only amid so many up votes, because I don't think Pascal was quite so oblivious as the answer suggests. I mean...he was Pascal. I don't think Pascal's wager had as much to do with the specific nature of even his very dogmatic God as with the nature of probability and certainty. It is, like Berkeley, an argument against easy skepticism, not the assumption of specific attributes of God.
We go to heaven through faith, (not by works so that no man can boast). 1D and most of 1E are ruled out.
@BaldBantha Maybe according to your faith. But not according to some other christian denominations, and not according to the uncountably infinite number of other possible religions and gods that you can or can't imagine. We're not talking about what YOU have assumed, the answer is talking about what Pascal assumed.