The principal customers aimed for are other economists or members of other professions, who are somewhat closer to the making of policy recommendations... The question of the clientèle is even more baffling when the problem concerns growth paths for time spans covering several generations. What can at best be recommended in that case is the signal the present generation gives, the tradition it seeks to strengthen or establish, for succeeding generations to take off from.

p. 244, as cited in: Vincent Martinet (2012) Economic Theory and Sustainable Development. p. 90 - Concepts of Optimality and Their Uses, 1975