We present a simple mechanism that can be implemented in a simple experiment. In a modified trust game, the allocator can offer to pay the investor to cooperate. The mechanism is successful at implementing efficient outcomes: participants manage to achieve an efficient outcome, when this is...

We show that all the fundamental properties of competitive equilibrium in Marshall's theory of value, as presented in Note XXI of the mathematical appendix to his Principles of Economics (1890), derive from the Strong Law of Demand. This is, existence, uniqueness, optimality, global stability of...