Why Time Discounting Should Be Exponential: A Reply to Callender

According to Craig Callender [2022], the 'received view' across the social sciences is that, when it comes to time and preference, only exponential time discounting is rational. Callender argues that this view is false, even pernicious. Here I endorse what I take to be Callender's main argument, but only in so far as the received view is understood in a particular way. I go on to propose a different way of understanding the received view that makes it true. In short: When time discounting is suitably conceived, the exponential form of the discounting function is indeed uniquely rational.