4.3 Blaise Pascal

Theoretical rationality

concerns making decisions (and drawing conclusions) based on argument and evidence: aimed at truth

Practical rationality

concerns making decisions (and drawing conclusions) based on what is in your best interests

Basic idea of Decision theory

identify all possible options for a given problem and determine the expected utility (measure of benefit) of each choice, Agents do not always in fact choose the outcome with highest utility (as psychological experiments show), but we are concerned with what they should do. Pascal's Wager involves choice under conditions of uncertainty, and he applies basic concepts of decision theory to derive a conclusion (we will formalize this)

What does pascal claim we should believe?

that God exists (in the practical, not theoretical, sense of "should")

Decision theory studies decisions under what conditions?

uncertainty with a specified number of possibilities (importance in economics, for instance) How to make the best or most rational choice? Decision theory concerns practical rationality

Assumptions

Pascal claims he makes no metaphysical assumptions about the nature of God Pascal believes that neither rational argument nor evidence can prove the existence of God Pascal claims that you must wager on the existence of God - make the bet that is in your best interest Pascal claims we should believe that God exists Pascal implicitly assumes a difference between theoretical rationality and practical rationality (our distinction, but it is present in Pascal's reasoning)