We address in this paper the question of the existence of a Social Welfare Function that would be sustainable and would allow us to obtain solutions to optimal growth models. We define sustainability by two new axioms called Never-decisiveness of the present and Never-decisiveness of the future....

We extend the Beltratti, Chichilnisky and Heal's (1993) and (1998) continuous-time stochastic dynamic framework to analyze the optimal depletion of an asset whose consumption is irreversible, in the face of uncertainty about future preferences. Their model is rather general and so the results...