ECONOMY

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whether direct or indirect, “implements” the social choice function recommended by
endstate justice.
If endstate justice is the only motivation of our benevolent dictator, the choice of
the game form G is “value free” and we can take an opportunistic attitude toward
the resolution of the implementation problem. Any mechanism with the correct
equilibrium outcomes (as specified by the social choice function) is legitimate, even
if this involves one or more of the following features:
endowing agents with unequal rights (a non-anonymous game form), even
though the social choice function to be implemented is anonymous and treats
equal agents equally;
using coercive threats to extract private information from the agents and/or to
influence their strategic choices; metaphorically speaking, burning the agents’
feet to make them reveal their characteristics under duress;
using more subtle, yet no less objectionable, twists to force the agents to
reveal mutually their private information, as in the mechanisms introduced
by Maskin (1985) amounting to a sophisticated version of “unanimity at gunpoint:”
the agents must unanimously agree in their report about the entire
profile of characteristics, lest the dictator enforces an endstate very bad for
everyone;
changing the game form frequently, as dictated by circumstantial information,
for instance about the statistical distribution of individual characteristics.
These features run contrary to the simple and pervasive intuition that agents do
care about their rights and about the decision process. In the case of the implementation
problem, this means that the benevolent dictator should not be allowed to extract
the private information held by individual agents in any way she pleases. She should
not bully them into revealing information without giving them some real influence
on the process itself. Not to place any limits on the procedures that can be used
affords her too much power. Means matter as well as ends.
5 Endstate Justice cum
Procedural Justice
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Granted that means matter as well as ends, what is the next logical step? How can we
combine endstate and procedural justice in the general model of Section 2?
In this section we define formally the concepts of strategy-proofness and group
strategy-proofness. We submit that they provide a general answer to the above question.
We postpone until the next section the discussion of examples showing these
two concepts at work.
Assume from now on that R i represents a preference ordering over X, and varies
within the domain R, known to the mechanism designer, who however is not aware