People are willing to pay people future money that increases exponentially in exchange for money now (stock trends bear this out and many other sorts of investments are inherently exponential). If we make the (bad, unendorsed by me) simplification that utility is proportional to money, people are willing to pay an exponential amount of future utility for current utility—that is, they discount the value of future utility.
May I ask how the doubling time of the economy can suggest how we discount future utility?
People are willing to pay people future money that increases exponentially in exchange for money now (stock trends bear this out and many other sorts of investments are inherently exponential). If we make the (bad, unendorsed by me) simplification that utility is proportional to money, people are willing to pay an exponential amount of future utility for current utility—that is, they discount the value of future utility.