Blaise Pascal is best remembered for his contributions to mathematician, physics, and for Pascal's Wager:
"God is, or He is not." But to which side shall we incline? Reason can decide nothing here. There is an infinite chaos which separated us. A game is being played at the extremity of this infinite distance where heads or tails will turn up... Which will you choose then? Let us see. Since you must choose, let us see which interests you least. You have two things to lose, the true and the good; and two things to stake, your reason and your will, your knowledge and your happiness; and your nature has two things to shun, error and misery. Your reason is no more shocked in choosing one rather than the other, since you must of necessity choose... But your happiness? Let us weigh the gain and the loss in wagering that God is... If you gain, you gain all; if you lose, you lose nothing. Wager, then, without hesitation that He is."The wager, which is the first known example of probability theory and decision theory, appeared in Pascal's unpublished Pensées. In this argument, Pascal attempts to provide prudential reasons for believing in God. He maintains that we should wager that God exists because to do so is the best bet or the safest bet.
There are many problems with the wager, not least of which is the fact that we cannot will ourselves to believe in something for which we do not already possess belief.
Other problems include the fact that the God in whom Pascal is suggesting 'prudent' belief may not in fact be the actual deity. If the actual deity is as jealous and vengeful as the Christian God is portrayed as being, then having wasted time in devotions to the Christian God might be less prudent than no belief at all. There are more problems with the wager detailed at the resources below.
Despite the fact that the wager fails as an argument for belief, it does capture the believer's emotional anticipation anticipation of reward for belief. In this sense, it is quite revealing of the self-centered reasons for theistic belief.
"It is better to live your life as if there are no Gods, and try to make the world a better place for your being in it. If there is no God, you have lost nothing and will be remembered fondly by those you left behind. If there is a benevolent God, He will judge you on your merits and not just on whether or not you believed in Him."or,
"Instead, my wager is that if there is a god, and it is a just god, then living a just and moral life will be acknowledged regardless of ones beliefs. If there exists an unjust or immoral god, then I could never satisfy both my conscience and such a god. My wager is that if the Christians are right about god being just and all-knowing and all-loving, I will be rewarded if I act in morally sound, justified ways.
I don’t know if there is a god. To me, the idea of a god, or even of an afterlife pales in importance to what we experience everyday. Life is the only thing that I “know” I have and when that is gone, I doubt I’ll be around to care, however, others will. I must live my life as I please, and since I believe I will only ever get one chance at it, I want to live it in the best manner that I can and help others do the same. "
or, more amusingly
"Any deity this argument applies to is evil. Honestly, E-V-I-L... You might as well take the Atheist's Wager. Do good, then if there's a evil God everybody is still screwed. If there is a good God then you go to heaven, if there is no God then doing good is its own reward." Tatarize, here.
"Be a good person, by your own good faith beliefs and efforts, and don't bother with what God thinks.
If God is a capricious evil bastard who keeps changing the rules and doesn't play by them anyway, it doesn't matter what you do. You have no way of knowing what he'll reward or punish. So you might as well just do what you think is right, regardless of what God may or may not think.
If God is good, by any reasonable definition of the word "good" that we can comprehend, then he'll reward you for being a good person regardless of whether you believe in him or not.
And if God doesn't exist, there are still plenty of reasons to be a good person: feeling empathy for people and a sense of connection with them, yada yada yada." ~ Greta Christina, here.
Pascal's Wager and refutations on Infidels.com.
Pascal's Wager in the Internet Encyclopedia of Philosophy
Hájek, Alan, "Pascal's Wager", The Stanford Encyclopedia of Philosophy (Spring 2004 Edition), Edward N. Zalta (ed.), url.
The Rejection of Pascal's Wager.
The End of Pascal's Wager: Only Nontheists Go to Heaven (2002).
Pascal's Wager on the OCRT site.
The Empty Wager.
Pascal's Wager or Pascal's Gambit (wikipedia)
Blogs: The Atheist's Wager, or Why Blaise Pascal Can Go Suck an Egg