Stony Brook University

certain natural antipathy stands between the heart and whatever one calls sin.” This view
is consistent with the Christian notion of the instinct of natural law, stemming from St.
Paul’s saying in Romans 2:15, that the natural law is written in our hearts. 92 But
Leibniz’s concluding point for this whole summary of historical opinion is the following:
These [opinions] we will easily reconcile, explaining our own opinion.
Namely, the Right of Nature has three degrees: strict right, equity, and
piety. 93
Leibniz’s claim here is enormously significant. He claims that these positions may be
summed up by what is found in the “three degrees of natural right [or natural law].” He
has taken and modified this claim from a single sentence of the Roman Digest, namely:
“the precepts of right are these: to live honestly, to harm no one, to give to each his
own.” 94 What he will now show is not so much how the history of natural right is
reconciled in them, but rather how these precepts derive from the definitions established
above. These “three degrees” will become essential components of his practical
philosophy from now on.
The following sections of the Nova Methodus (§§73-76) are crucial for an
adequate understanding of the science of jurisprudence in the Nova Methodus, not to
mention for Leibniz’s entire practical philosophy. 95 Following from his definitions, the
three degrees or precepts of natural right are supposed to complement the science of
jurisprudence. 96 Here is an overview of the three degrees and their corresponding
precepts, as Leibniz configures them. The first (and “lowest”) degree is called “strict
right” (jus strictum) and its precept is “to harm no one” (neminem laedere). The second
degree is called “equity” (aequitas), and its precept is “to give each his due” (suum
cuique tribuere). The third and highest degree is “piety” (pietas) and its precept is “to live
honorably” (honeste vivere). Leibniz also thinks of these degrees as perfections. This
recalls his general claim at the beginning of the Nova Methodus that the aim of the
science of jurisprudence is the perfection of the jurisconsult. But in particular, this means
that each degree is a perfection or completion of the preceding one. “From these degrees,
each following one is more perfect than the previous and confirms [or strengthens] it, and
in controversial cases the lower one is withdrawn.” 97 Thus, the law determined by the
higher degree holds priority over the law determined by the lower. These points should
be kept in mind as we now turn to the details.
92
As I will show in Chapter Five, Leibniz treats this law as expressing (a) the double command of love and
(b) as well what “reason commands” (Nouveaux essais, A.6.6.92.§9).
93
A.6.1.343.§73: “Hos facile inter se conciliabimus, explicata nostra sententia. Scilicet Juris Naturae tres
sunt gradus : Jus strictum, aequitas, pietas.” I translate juris naturae as ‘the law of nature,’ but it could also
be translated as ‘the right of nature’ or ‘natural law’ as it is by others. Busche’s German translation is "Es
sind naemlich drei Stufen des Naturrechts zu unterscheiden.”
94
Ulpian, Digesta, 1.1.10: “Iuris praecepta sunt haec: honeste vivere, alterum non laedere, suum cuique
tribuere.” Ulpian’s precepts had originally appeared in Regulae Ulpiani, Book 1.
95
Surprisingly little of these sections has been translated into English. Mulvaney (1968) has translated
some of them.
96
See Busche, pp. lxviii- xciii for thorough background on the three degrees. Also see Grua (1956) pp. 77-
95 and H-P Schneider (1967) pp. 352-356; 401-420.
97
A.6.1.343.§73: “Quorum sequens antecedente perfectior, eumque confirmat, et in casu pugnantiae ei
derogat.” I’m not confident in this translation.
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