Blaise Pascal argued the following:
If you erroneously believe in God, you lose nothing; whereas, if you correctly believe in God, you gain everything. But if you correctly disbelieve in God, you gain nothing; whereas, if you erroneously disbelieve in God, you lose everything.
The Atheist's Wager retorts:
In your life, try to improve the world, whether you believe in god or not. If no god exists, you have lost nothing and will be remembered fondly by people whose lives you touched. If there is a benevolent god, he will judge you on your merits and not your belief in him.
Either way, an eternally happy afterlife is rather unlikely:
The set of all possible gods and the subset of wrathful, omnipotent, jealous gods are also infinite; those wrathful gods punish disbelievers eternally.
The odds of worshipping the One True God approach zero as the number of possible (wrathful) gods approaches infinity.
Therefore, even if some gods promote a happy afterlife, the odds of being accepted by those that do is essentially zero, regardless of religious beliefs.
Checkmate, theists.
