Stony Brook University

In the following section (§74) Leibniz turns, although briefly, to the second
degree of natural right, which he calls “equity” and whose precept is “to give each his
own.” 112 In general, this degree is an amplification or extension of strict right. As noted,
strict right was called “commutative justice” and was characterized by arithmetical
equality. In the second degree, the mathematical character is a bit different, as can be
seen in the first few sentences.
Equity or equality, that is, the ratio or proportion between two or more
rights claims, consists in harmony or congruence. This coincides with the
principles of Aristotle, Grotius, and Felden. This requires that, for he who
harms me, no murderous war is perpetuated, but rather restitution. 113
The phrase ‘equity or equality’ refers to geometrical equality, which is called simply
equity. The point is that the second degree of natural right involves, not strictly reciprocal
relations, but proportional ones, that is, relations of equity and merit 114 . This is
exemplified in the case of harm; it is not equitable to return to a state of war with another,
but rather to be compensated for damages. Equity may also involve distributions
according to need. As noted in §73, the kind of justice that Aristotle and Grotius
identified with merit is called distributive. Thus, the notions of equity, merit, proportion,
and need are contained in the precept, “to give each his due.” 115
This move from strict right to equity may indicate a move toward positive law;
however, equity remains within the normative sphere of right. This is indicated by the
above reference to “murderous war” and “restitution.” In the first degree, the right of war
is granted; yet in the second degree, this right is replaced by the right of compensation
and punishment, through arbitration. The motivation for this move seems to be that a
much broader set of communal relations simply requires government regulation to avoid
greater harm. Leibniz recognizes that the hazards of self-rule and the tendency for
revenge require the management of force through the rule of law. For these reasons
Leibniz introduces a rule of judgment (or, a rule for the judge): “what you do not want to
have done to yourself, do not do to others.” This is the negative version of the so-called
Golden Rule. 116
Leibniz does not indicate how this rule is to be applied, or how it reflects the right
112
Note the definition of justice from the Digest (I.1.10): “Iustitia est constans et perpetua voluntas ius
suum cuique tribuendi”.
113
A.6.1.343-4.§74: “Aequitas seu aequalitas, id est, duorum pluriumve ratio vel proportio consistit in
harmonia seu congruentia. Et coincidit cum Principiis Aristotelis, Grotii et Feldeni: Haec requirit, ut in eum
qui me laesit, non bellum internecinum instituam, sed ad restitutionem;”
114
Busche (fn.129 p. 430) provides the following: In his doctoral dissertation, de Causibus Perplexis in
jure (1666), Leibniz had said that equity is geometric equality, which is to say that equity is a relation of
proportion or congruence between two or more claimants. A.6.1.249.27: “daturque aequilibrium justitiae,
cum libra paria utrinque pondera sustinet. Idem et aequitati (id est aequalitatis Geometricae congruum.
Nam, ut ingeniose definit Vultejus in Jurisp. Rom. pr., aequitas duorum pluriumve proportio est, id est, ut
participent de jure pro rata meritorum causae.”
115
Leibniz adds some clarification in a later revision note to §74, Z. 7-9 : “Ad hunc juris gradum justitia
distributiva pertinet et praeceptum qvod jubet: suum cuique tribuere.”
116
A.6.1.344.§74: “arbitros admitti, quod tibi nolis, alteri non faciendum;” This is a notable point. Leibniz
has a special version of the Golden Rule which he uses as the measure of justice in Meditation on the
Common Notion of Justice, as we will see.
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