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Reality Checks

Pascal’s Wager

The French mathematician and philosopher Blaise Pascal was probably
the first to combine philosophy and probability. Pascal was willing to ac-
knowledge the possibility that God might not exist, but argued that the
rational individual should believe in God. His argument was based on
the probabilistic concept of expectation, which is the long-term average
value of a bet. If you bet that God existed and won, the payoff was life ever
after—and even if the probability that God existed was small, the average
payoff from making this bet dwarfed the average payoff you would re-
ceive if God did not exist. A slightly different version of this is to look
under the streetlight if you lose your car keys one night—the probability
of the keys being there may be small, but you’ll never find them where it’s
dark.
As the nineteenth century dawned, some of the leading thinkers of the
era noted the success of physics and chemistry, and tried to apply some of
the ideas and results to the social sciences. One such individual was Au-
guste Comte, who was one of the creators of the discipline of sociology,