Background Probability Theory Pascal's Triangle & Probability Application of Probability Theory Pascal's wager Objections Homework Joyce Lam Nga Ching 2001714828 Phil1007 12-4-2002 27-4-2002
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Pascal's Wager 2nd Argument:Argument from Expectation The uncertainty of the decision lead to the second argument: a Pascal’s wager is a decision situation in which the possible gain or benefit involved in one of the outcomes swamps all the others. With Pascal’s wager, the possible gain of theism is supposed to be not just greater than that of nonbelief, it is of a cardinality infinitely greater. Because attached to theistic belief is nonpareil. It is not a religious topic. It is a swamping property as involving not an infinite value only but as a gain that is vastly greater than any of its rivals. This gain is so great as to render the probability assignments, even if they are known, virtually irrelevant. The
second argument is the Argument from Expectation. It is an argument that we
should consider the expectation when you make a decision under risk so as to
gain maximum expected utility. A certain decision or action is associated with a set of possible outcomes and each outcome has a certain value or utility. The expectation for each outcome is equal to its utility multiplied by the probability of its happening. The expectation for a given action is the sum of the expectations for each possible associated outcome. The course of action having the maximum expectation is the rational one to follow. When
you make the decision under risk, you should calculate the expected utility that
is the expectation of a given action produces in that state by the state’s
probability. According to decision theory, rationality requires you to perform
the action of maximum expected utility. The three assumptions in this argument are: 1.there is equal risk of gain and of loss(the probability of the existence of God is one-half) 2.the
wagering for God brings infinite reward if God exists. 3.I His
hypothetically speaking of "two lives" and "three lives" may
strike one as odd.There
are several cases that Pascal’s Wager argument suggested. Case 1: Win: gain one extra life = have two lives Lose: lose your life=have zero lives The expectation (one life gain) : Probability(God exists) × the gain +
Probability(God does not exist) × the loss = 0.5 ×2 + 0.5 ×0 = 1 Since the expectation just equals the entry fee," you might still play or you might not." Case 2: Win: gain two extra lives = have three lives
Lose: lose your life=have zero lives The expectation (two life gain): Probability(God exists) × the gain +
Probability(God does not exist) × the loss = 0.5 ×3 + 0.5 ×0 = 1.5 Since the expectation exceeds the entry fee, "you would be imprudent" not to accept this gamble. But consider now the case that there is infinite reward if you believe in God and God exists. You can gain an eternal life in heaven and have infinite lives if God exists and you win. You will lose our life if God does not exist and you lose. Case 3: Win: gain eternal life(in heaven) = have infinitely lives Lose: lose your life=have zero lives The expectation (eternal life gain) : Probability(God exists) × the gain +
Probability(God does not exist) × the loss = 0.5 ×infinity + 0.5 ×0 = infinity
Since wagering for God is rationally required even in the hypothetical case in
which one of the prizes is three lives, then all the more it is rationally
required in the actual case, in which one of the prizes is eternal life .Provide
there is some finite chance of winning, however small, the expectation
infinitely exceeds the entry fee, and the gamble should be run. The expected utility indicated in unit of life is
calculated. The decision matrix is as the following.
Since the top alternative has an infinite expectation regard less of the probability, while its rival has the uniform expectation of a single unit, betting on God is clearly the best plan. "There is no need to hesitate; you must risk all." In the argument, it shows that it is a wise bet to spend one life to win infinite lives with 50-50 odds. It is rational and warranted to have the bet on God’s existence. However, Pascal realizes that the value of 1/2 actually plays no real role in the argument, thanks to (2). This brings us to the third, and by far the most important, of his arguments. Reference: 1.http://plato.Stanford.edu/entries/pascal-wager 2. N.Warburton, Philosophy: the basics,( London, Routledge,1999).P31-33 3.R.Nicholas,Pascal’s Wager: A study of practical reasoning in philosophical theology, ( Notre Dame,University of Notre Dame Press,1985)
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