The usual procedure in the field of optimal growth consists in maximizing a (discounted or not) sum of instantaneous utilities, called welfare. Such an optimality criterion implies that preferences are independent over time. Following in the tradition of Irwing Fisher, Koopmans presented an...

In the field of optimal growth theory, since Ramsey's time it is frequent to maximize a welfare function consisting of the discounted sum of instantaneous utilities. Such an optimality criterion implies that preferences are independent over time. Following in the tradition of Irwing Fisher,...