Pascal’s Wager

PASCAL’S WAGER

[taken from my forthcoming book for Quercus, Greatest Philosophers.

According to Pascal, there are no rational grounds to support either belief or disbelief in the Christian faith. Reason cannot settle the matter one way or the other. So should we believe, or not?

Pascal suggests we approach this question as if it involved placing a bet. We have two options: we can believe, or we can fail to believe. What do we stand to win or lose in each case?

Well, if I believe, and there is a God, then I win big. My reward will be eternal happiness. But what if there is no God? Then obviously I won’t receive that fantastic reward. But still, my loss is not so very great. Little more than those Sunday mornings I had to spend in church.

If, on the other hand, I fail to believe in God, and God exists, I lose big, for I face eternal damnation. Nothing could be worse. And if I fail to believe in God, and there is no God, then I win, but then I don’t win very much. Not much more, in fact, than those free Sunday morning.

We can display these outcomes in a table, like so:

God exists God does not exist

Believe in God eternal bliss small loss of worldly
pleasures

Fail to believe in God eternal damnation small gain in worldly
Pleasures

Now, assuming that we have no more grounds to suppose God does exist than to suppose he doesn’t, surely the rational bet to make is to believe in God. If I believe, then I will either win big or lose a little. If I fail to believe, then I either win small or lose big. Belief is therefore the more sensible wager, concludes Pascal.

Pascal claims belief in God is the rational choice even though there are no more grounds for supposing the belief is true than there are for supposing it is false. His claim sounds paradoxical, but, correctly understood, it is not. Consider an analogous case. You are diagnosed with a disease that will certainly soon kill you unless you receive treatment. There is only one treatment, and it has a 50% success rate. When the treatment doesn’t work, its side-effects are rather unpleasant. What should you do?

Clearly, the rational choice, assuming you want to live, is to undergo the treatment, despite the fact that you have no more grounds to suppose it will work than you have to suppose it won’t. Undergo the treatment and you will either win big or lose little. Fail to undergo the treatment, and you will either lose big or win small.

If Pascal is correct, the option of believing in God is similarly one it would be irrational to refuse.

Objections to Pascal’s argument

Many have found Pascal’s argument persuasive, but it does run up against some well-known objections, including the following:

1. We cannot choose what we believe. First, some will respond, “But I can’t just choose to believe that God exists. It may be that, though I can see that belief in God is the rational bet, and so would very much like to believe it, I can’t manage it. Try as I might, belief eludes me.”
Pascal acknowledges that we can’t usually choose what we believe. Certainly we can’t just make ourselves believe something directly, by a sheer act of will. However, he notes that even those who merely start off by going through the motions of religious belief often end up true believers. So if I also make myself go though the motions – if I regularly go to church and pray – I am likely to end up a true believer. This is exactly what Pascal recommends I should do.

2. Pascal’s wager is based on a dubious assumption. Pascal supposes that the arguments and evidence for and against God’s existence are evenly balanced. But are they? Most atheists would deny this. Many would say the arguments and the evidence overwhelming support the claim that there is no God. If they are right about that – if, say, the odds of God existing are not 50-50, but more than 99-1 against – then it is not quite so obvious that belief in God is the rational bet.

To illustrate, let’s return to the medical example outlined above. If you are told the probability that the treatment will succeed is not 50%, but much less than one percent, then it is not so clear that the rational choice is to opt for treatment. Especially as you know that you will almost certainly experience some nasty side-effects as a result. Under these circumstances, you might well calculate that you would be better off rejecting treatment.

3. Another dubious assumption. Third, we might question whether Pascal is right to assume all believers will be rewarded with eternal bliss and all disbelievers with eternal damnation. If I was God, I wouldn’t be particularly impressed by someone who believed in me purely on the basis of a self-interested calculation. Nor, if I had deliberately arranged the evidence for my existence to be equivocal, would I condemn to eternal agony someone who then failed to believe in me. Such punishment seems rather harsh, particularly from a God who is supposed to be supremely benevolent.

So Pascal’s estimation of how God, if he exists, will react to our belief or disbelief – that he will reward all believers with limitless bliss and punish all unbelievers with an eternity of hellfire – is certainly open to question.