Rawls’ ‘Maximin’ Argument for the Two
Principles of Justice
(From A Theory of Justice, section 26 ,
“The Reasoning Leading
to the Two Principles of Justice)
It seems clear from
these remarks that the two principles are at least a plausible conception of
justice. The question, though, is how one is to argue for them more
systematically. Now there are several things to do. One can work out their
consequences for institutions and note their implications for fundamental social policy. In this way they are
tested by a comparison with our considered judgments of justice. Part II is
devoted to this. But one can also try to find arguments in their favor that are
decisive from the standpoint of the original position. In order to see how this
might be done, it is useful as a heuristic device to think of the two principles as the
maximin solution to the problem of social justice. There is an
analogy between the two principles and the maximin rule for choice
under uncertainty. This is evident from the fact that the two principles are those a
person would choose for the design of a society in which his enemy is to assign him
his place. The maximin rule tells us to rank alternatives by their worst possible outcomes:
we are to adopt the alternative the worst outcome of which is
superior to the worst outcomes of the others. The persons in the
original position do not, of course, assume that their initial place in
society is decided by a malevolent opponent. As I note below, they should not
reason from false premises. The veil of ignorance does not violate this idea,
since an absence of information is not misinformation. But that the two
principles of justice would be chosen if the parties were forced to protect
themselves against such a contingency explains the sense in which this
conception is the maximin solution. And this analogy suggests that if the original position has been
described so that it is rational for the parties to adopt the conservative attitude expressed by this rule, a conclusive
argument can indeed be constructed for these principles. Clearly the maximin rule is not, in general, a
suitable guide for choices under
uncertainty. But it is attractive in situations marked by certain special features. My aim, then, is to
show that a good case can be made for
the two principles based on the fact that the original position manifests these
features to the fullest possible degree, carrying them to the limit, so
to speak.
Consider the gain-and-loss table below.
It represents the gains and losses for a situation which is not a game of
strategy. There is no one playing against the person making the decision; instead
he is
faced with several possible circumstances which may or may not obtain. Which
circumstances happen to exist does not depend upon what the person choosing
decides or whether he announces his moves in advance. The numbers in the
table are monetary values (in hundreds of dollars) in comparison with some
initial situation. The
gain (g) depends upon the individual's decision (d) and the circumstances (c). Thus
g = f (d, c). Assuming that there are
three possible decisions and three possible circumstances, we might have this gain-and-loss table.
|
|
Circumstances |
||
Decisions |
|
C1 |
C2 |
C3 |
|
|
|
|
|
D1 |
|
-7 |
8 |
12 |
D2 |
|
-8 |
7 |
14 |
D3 |
|
5 |
6 |
8 |
The maximin rule requires that we make
the third decision. For in this case the worst that can happen is that one gains
five hundred dollars,
which is better than the worst for the other actions. If we adopt one of these we may lose either eight or
seven hundred dollars. Thus, the choice
of d3 maximizes f(d,c) for
that value of c, which for a given
d, minimizes f. The term "maximin" means the maximum minimorum; and
the rule directs our attention to the worst that can happen under any proposed course of action, and to
decide in the light of that.
Now there appear
to be three chief features of situations that give plausibility to this unusual
rule. First, since the rule takes no account of the likelihoods of the possible
circumstances, there must be some reason for sharply discounting estimates
of these probabilities. Offhand, the most natural rule of choice would seem to
be to compute the expectation of monetary
gain for each decision and then to
adopt the course of action with the highest prospect. (This expectation is defined as follows: let us suppose
that gij represent the numbers in the gain-and-loss table, where i is the row index and j is the column index; and let pj, j
= 1, 2, 3, be the likelihoods of the
circumstances, with ∑pj = 1. Then
the expectation for the ith decision is equal to ∑pj gij.)
Thus it must be, for example, that the situation
is one in which a knowledge of likelihoods is impossible, or at best extremely insecure. In this case it is
unreasonable not to be skeptical of
probabilistic calculations unless there is no other way out, particularly if the decision is a
fundamental one that needs to be justified to others.
The second
feature that suggests the maximin rule is the following: the person choosing
has a conception of the good such that he cares very little, if anything, for what
he might gain above the minimum stipend that he can, in fact, be sure of by
following the maximin rule. It is not worthwhile for him to take a chance
for the sake of a further advantage, especially when it may turn out that he loses much that
is important to him. This last provision brings in the third feature, namely, that
the rejected alternatives have outcomes that one can hardly accept. The situation
involves grave risks. Of course these features work most effectively in
combination. The paradigm situation for following the maximin rule is when all
three features are realized to the highest degree. This rule does not, then, generally apply, nor of course is it self-evident. Rather, it is a maxim, a rule of thumb, that comes into its own in special circumstances. Its application depends
upon the qualitative structure of the
possible gains and losses in relation to one's conception of the good, all this against a background
in which it is reasonable to discount
conjectural estimates of likelihoods.
It should be
noted, as the comments on the gain-and-loss table say, that the
entries in the table represent monetary values and not utilities. This
difference is significant since for one thing computing expectations on
the basis of such objective values is not the same thing as computing
expected utility and may lead to different results. The essential point though
is that in justice as fairness the parties do not know their conception of
the good and cannot estimate their utility in the ordinary sense. In any case,
we want to go behind de facto preferences generated by given conditions.
Therefore expectations are based upon an index of primary goods and the parties make
their choice accordingly. The entries in the example are in terms of
money and not utility to indicate this aspect of the contract
doctrine.
Now, as I have
suggested, the original position has been defined so that it is a
situation in which the maximin rule applies. In order to see this, let
us review briefly the nature of this situation with these three
special features in mind. To begin with, the veil of ignorance excludes
all but the vaguest knowledge of likelihoods. The parties have no basis for
determining the probable nature of their society, or their place in it. Thus
they have strong reasons for being wary of probability calculations if any other
course is open to them. They must also take into account the fact that their
choice of principles should seem reasonable to others, in particular their descendants, whose
rights will be deeply affected by it. There are further grounds for discounting
that I shall mention as we go along. For the present it suffices to note that these
considerations are strengthened by the fact that the parties know very little
about the gain-and-loss table. Not only are they unable to conjecture the likelihoods of
the various possible circumstances, they cannot say much about what
the possible circumstances are, much less enumerate them and foresee the outcome
of each alternative available. Those deciding are much more in the dark than
illustrations by numerical tables suggest. It is for this reason that I have
spoken only of a relation to the maximin rule.
Several kinds of
arguments for the two principles of justice illustrate the second feature.
Thus, if we can maintain that these principles provide a workable theory of
social justice, and that they are compatible with reasonable demands of
efficiency, then this conception guarantees a satisfactory minimum. There may be, on
reflection, little reason for trying to do better. Thus much of the argument ... is to show, by their application to some main questions of social justice, that the
two principles are a satisfactory conception.
These details have a philosophical purpose. Moreover, this line of thought is practically decisive if we can establish the priority of liberty. For
this priority implies that the
persons in the original position have
no desire to try for greater gains at the expense of the basic equal liberties. The minimum assured
by the two principles in lexical order
is not one that the parties wish to
jeopardize for the sake of greater economic
and social advantages.
Finally,
the third feature holds if we can assume that other conceptions of justice may lead
to institutions that the parties would find intolerable. For example, it
has sometimes been held that under some conditions the utility principle (in
either form) justifies, if not slavery or serfdom, at any rate serious infractions
of liberty for the sake of greater social benefits. We need not consider here
the truth of this claim. For the moment, this contention is only to illustrate
the way in which conceptions of justice may allow for outcomes which the
parties may not be able to accept. And having the ready alternative of
the two principles of justice which secure a satisfactory minimum, it seems
unwise, if not irrational, for them to take a chance that these conditions are
not realized....