"Pascal's Wager," so-called because it was devised by the brilliant Catholic philosopher Blaise Pascal (1623-1662), is an apologetics method in the form of a wager aimed at getting atheists and agnostics to consider the possibility that God exists and that there is a heaven and hell. The beauty of Pascal's Wager is that it is an appeal to the chief god worshipped by atheists: their reason. Fr. Joseph H. Cavanaugh, C.F.C., explains in his apologetics handbook, Evidence for Our Faith,
Pascal addresses his argument to the typical man of the world who regards making money and amusing himself, not as a means to the end, but the real purpose of existence. Even if he refuses to consider his ultimate destiny, Pascal maintains such a man cannot avoid wagering about it. In practice, he must stake everything on one of two propositions, either (A) that there is a purpose in life (God made us for life with him); or (B) that there is not. Man cannot refuse to wager for by doing so he implies that there is no purpose in life.
Under one guise or another, human selfishness is always urging man to stake everything on B. Pascal tries to show that it is far more reasonable - even from the viewpoint of self-interest - to stake all on A. If you bet everything on B and A is the truth, you lose an eternal good. But if you stake all on A and B is the truth, you lose only a few temporal pleasures.
Pascal describes the thoughts of the typical man in these word:, "I know not whence I came or whither I go. I only know that on quitting this world, I shall fall forever either into nothingness or into the hands of an angry God [Heb 10:31] . . . And yet I conclude that I should pass all the days of my life without bothering to inquire into what must happen to me. Perhaps I might find some solution to my doubts, but I do not want to take the trouble. . . I intend to go forward without looking ahead and without fear toward this great event, facing death carelessly, still uncertain as to the eternity of my future state" (Pensees III, 194). . . . In other words, Pascal thinks it is not merely a moral tragedy but an intellectual blunder to wager on B, that is, to refuse to recognize a purpose in life. He feels sure the typical man would soon have faith if he renounces pleasure. At least he should search for the truth. "According to the doctrine of chance, you should search earnestly for the truth, for if you die without worshipping the True Cause, you are lost. 'But,' you say, 'if God had wished me to worship him, he would have left me Signs of his will.' Indeed, God has done so (Rom 1:18-21; 2:14- 16); but you ignore them. "