Pascal’s Wager is an attempt to justify belief in God not with an appeal to evidence for his existence but rather with an appeal to self-interest. It is in our interests to believe in the God of Christianity, the argument suggests, and it is therefore rational for us to do so.

The argument is attributed to Blaise Pascal on the basis of a section of his Pensees entitled “Infini-rien”. Some defenders of Pascal insist that his argument there is both more subtle and more defensible than the argument that we now call “Pascal’s Wager”. However, Pascal’s Wager has achieved sufficient popularity to warrant discussion irrespective of whether it is what Pascal intended in Infini-rien.

Pascal’s Wager seeks to justify Christian faith by considering the various possible consequences of belief and disbelief in the God of Christianity. If we believe in the Christian God, the argument runs, then if he exists then we will receive an infinitely great reward in heaven while if he does not then we will have lost little or nothing. If we do not believe in the Christian God, the argument continues, then if he exists then we will receive an infinitely great punishment in hell while if he does not then we will have gained little or nothing. The possible outcomes of belief in the Christian God, then, are on balance better than the possible outcomes of disbelief in the Christian God. It is better to either receive an infinitely great reward in heaven or lose little or nothing than it is to either receive an infinitely great punishment in hell or gain little or nothing.

The conclusion that Pascal’s Wager draws from this is that belief in the Christian God is the rational course of action, even if there is no evidence that he exists. If the Christian God does not exist then it is of little importance whether we believe or disbelieve in him. If the Christian God does exist then it is of great importance that we do believe in him. In order to cover ourselves in all circumstances, therefore, we ought to believe that the Christian God exists. A formal statement of this argument might be constructed as follows:

Pascal’s Wager

(1) It is possible that the Christian God exists and it is possible that the Christian God does not exist.
(2) If one believes in the Christian God then if he exists then one receives an infinitely great reward and if he does not exist then one loses little or nothing.
(3) If one does not believe in the Christian God then if he exists then one receives an infinitely great punishment and if he does not exist then one gains little or nothing.
(4) It is better to either receive an infinitely great reward or lose little or nothing than it is to either receive an infinitely great punishment or gain little or nothing.
Therefore:
(5) It is better to believe in the Christian God than it is not to believe in the Christian God.
(6) If one course of action is better than another then it is rational to follow that course of action and irrational to follow the other.
Therefore:
(7) It is rational to believe in the Christian God and irrational not to believe in the Christian God.

Three common objections to this argument will be considered here.

The Entrance Criteria for Heaven

The first of these objections targets the third premise of the argument as it is stated above. It is the objection that Pascal’s Wager illicitly assumes a Christian view of the criteria for admission into heaven, i.e. it illicitly assumes that if there are infinite rewards and punishments to be had then they will be distributed on the basis of belief or disbelief in the Christian god.

There are many possible ways in which such rewards and punishments might be distributed; they might be distributed on the basis of belief in the Christian God, or on the basis of good deeds, or on the basis of belief in the Muslim God, for instance. In fact, distribution of heavenly rewards and infernal punishments on almost any basis imaginable appears to be possible.

It is only, however, if such rewards and punishments are distributed on the basis of belief in the Christian God that belief in the Christian God is in our interests. On many of the other possible distributive schemes, it is by disbelieving in the Christian God that one receives a heavenly reward. If any of those distributive schemes were the true scheme, though, then the third premise of Pascal’s Wager would be false. It would not be the case that if one does not believe in the Christian God and the Christian God does not exist then one gains little or nothing, for if such a distributive scheme were the true scheme then one might gain a great deal (i.e. an infinite reward in heaven) by disbelieving in the Christian God.

In order to demonstrate that the third premise of his argument is true, then, the advocate of Pascal’s Wager must demonstrate that the only possible criterion for entrance into heaven is belief in the Christian God and the only possible criterion for entrance into hell is disbelief in the Christian God. This, the objector suggests, cannot be demonstrated, for it is false. Based on a similar thought to this, Michael Martin has argued that pragmatism recommends atheism rather than theism.

The Existence of God is Unlikely

The second objection to Pascal’s Wager targets the fourth premise of the argument as it is stated above. It is the objection that the probability that God exists, and so the probability of either receiving an infinite reward in heaven or of receiving an infinite punishment in hell, is so small that these possible outcomes of belief or disbelief can be discounted.

The choice between belief and disbelief is thus taken to be a choice between losing little or nothing and gaining little or nothing. As it is better to gain little or nothing than it is to lose little or nothing, this objection concludes that it is wagering on atheism, rather than wagering on theism, that is the rational course of action. It is better, the objection suggests, to take the certain benefits of disbelief (the joys of indulging in sin and of being free from religious commitments) by wagering that God doesn‘t exist than it is to gamble on the vastly improbable hope of a heavenly reward and almost certainly gain nothing at all.

We Cannot Choose Our Beliefs

The third objection targets the inference from the fifth and sixth premises to the conclusion. It is the objection that we cannot choose our beliefs. We form our beliefs on the basis of evidence, not on the basis of desire. No matter how much one may want to believe that a given proposition is true, one cannot bring oneself to do so simply through an act of will. Rather, in order for one to come to believe that a proposition is true one requires evidence for its truth. Pascal’s Wager, though, merely prescribes belief in God; it does not provide any evidence that such a belief would be true. As such, it asks us to do the impossible: to believe without reason.