Pascal and Religion

Some people’s attitude about religion is that one of the reasons to believe in religion is because it might just be true and, if it is true, you are better off believing than not. The French mathematician and philosopher, Blaise Pascal, justified this course of action with his famous wager, which was published in a book of his “Thoughts” (or Pensées) in 1670, eight years after Pascal died. The logic that Pascal applied was considered a milestone in probability theory and decision theory. His argument went roughly as follows: If God exists and you don’t believe in him, then you are condemned to eternal hell. If God does not exist and you believe in him, then you get nothing bad out of that belief. Thus it is better to believe in God just in case he actually exists. So even if you believe the probability of God’s existence is just one in ten thousand (or 0.0001), the expected return for believing is much better than that: