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The just—or permitted, forbidden, owed, free—is what for the good and
prudent person is possible, impossible, necessary, contingent. Thus right is
a moral power and obligation is a moral necessity. 23
Still using the familiar categories, subjective right appears to be the logical basis of the
just, good, and prudent person. As in the Nova Methodus, what must now be indicated is
the object of subjective right, i.e., the objective sphere of right. We need to know more
specifically which actions may be done by the good and wise person. This begins to be
indicated in the very next sentence—which indicates at least the sort of actions that are
not to be done.
For those actions which harm our piety or respect and which are entirely
against good morals, [the good person] can neither do nor believes it is
possible to do. 24
We should also recall that this passage was introduced in the Elementa and it is taken
directly from the Digest. 25 But in a way this is a curious statement, since mores in some
contexts denotes “customs,” which, even though etymologically related, means
something quite distinct from morals, if he indeed means the latter. At least, Leibniz is
committed to maintaining the distinction between morals and mores. If right is going to
be an a priori demonstrative science, if right is to be separate from fact, then right cannot
be identified with the contingent customs of a people or society. In any case, provided he
does not mean merely customs, the question still remains: what is it that harms piety,
respect, and offends good morals? The answer, at this point, appears to come next and is
again drawn from the Digest: whatever is against the conservation of society.
Now the designations of right have various senses, as can be seen in the
penultimate and last sentences of “On Justice and Right.” [ 26 ] Sometimes,
right is taken as the faculty, as we have defined it shortly before,
sometimes as right reason itself, which is what directs and conserves
human society. 27
These “designations of right” (to be explained in a moment) are jus naturale, jus gentium
and jus civile. These are also discussed in the Digest’s version of “On Justice and Right”
23 A.6.4.2778: “Justum vel Licitum, Illicitum, Debitum, Liberum est, quod est viro bono et prudenti
possibile, impossibile, necessarium, contingens. Hinc JUS est potestas moralis, OBLIGATIO necessitas
moralis.” Notably jus is defined in terms of potestas, not potentia. Leibniz seems not always to distinguish
these terms.
24 A.6.4.2778: “Nam quae facta laedunt pietatem nostram aut verecundiam, et omnino quae contra bonos
mores sunt, ea nec facere nos posse credendum est, l. 15. D. de conditionibus et demonstrationibus.” The
passage Leibniz is referring to is actually found in Lib 28, Tit. 7, Section 15 of the Digest: “nam quae facta
laedunt pietatem existimationem verecundiam nostram et, ut generaliter dixerim, contra bonos mores fiunt,
nec facere nos posse credendum est.”
25 See A.6.1.480
26 He means the end of Title 1, not the end of Book 1.
27 A.6.4.2778: “Juris tamen vocabulum varias habet acceptiones alias, vid. l. penult. et ult. D. de just[itia] et
jur[e.] Interdum enim jus sumitur pro facultate, ut paulo ante definivimus, interdum pro ipsa recta ratione,
quae societatem humanam dirigit et conservat.”
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