e real
mean, is to be followed: but justice follows the real mean; wherefore
the mean, in justice, depends on the diversity of things.

Reply Obj. 2: Equality is the general form of justice, wherein
distributive and commutative justice agree: but in one we find
equality of geometrical proportion, whereas in the other we find
equality of arithmetical proportion.

Reply Obj. 3: In actions and passions a person's station affects the
quantity of a thing: for it is a greater injury to strike a prince
than a private person. Hence in distributive justice a person's
station is considered in itself, whereas in commutative justice it is
considered in so far as it causes a diversity of things.
_______________________

THIRD ARTICLE [II-II, Q. 61, Art. 3]

Whether There Is a Different Matter for Both Kinds of Justice?

Objection 1: It would seem that there is not a different matter for
both kinds of justice. Diversity of matter causes diversity of
virtue, as in the case of fortitude and temperance. Therefore, if
distributive and commutative justice have different matters, it would
seem that they are not comprised under the same virtue, viz. justice.

Obj. 2: Further, the distribution that has to do with distributive
justice is one of "wealth or of honors, or of whatever can be
distributed among the members of the community" (Ethic. v, 2), which
very things are the subject matter of commutations between one person
and another, and this belongs to commutative justice. Therefore the
matters of distributive and commutative justice are not distinct.

Obj. 3: Further, if the matter of distributive justice differs from
that of commutative justice, for the reason that they differ
specifically, where there is no specific difference, there ought to
be no diversity of matter. Now the Philosopher (Ethic. v, 2) reckons
commutative justice as one species, and yet this has many kinds of
matter. Therefore the matter of these species of justice is,
seemingly, not of many kinds.

_On the contrary,_ It is stated in _Ethic._ v, 2 that "one kind of
justice directs distributions, and another commutations."

_I answer that,_ As stated above (Q. 51, AA. 8, 10), justice is about
certain external operations, namely distribution and commutation.
These consist in the use of certain externals, whether things,
persons or even works: of things, as when one man takes from or
restores to another that which is his; of persons, as when a man does
an inju