Stony Brook University

of a set of prudential instructions on how to achieve happiness, or that it is a mere
appendage to the grand scheme of metaphysical perfection. 166 But it seems possible to
understand the matter as precisely the opposite: The ends of metaphysical and moral
perfection depend on the premises established by jurisprudence. We should recall that
theology a species of the genus jurisprudence, universally understood. Is not God’s will
the supreme potentia moralis? To be a moral agent requires not simply the knowledge of
the conditions of metaphysical perfection, or the knowledge of the good for all, but
requires the self-restricting moral power to harmonize one’s ends with the ends of
everyone. This account of right sets Leibniz’s practical philosophy quite part from
accounts that ground it in utilitarian terms. 167 While the agent is indeed obligated to the
good for all, Leibniz is saying that this obligation is grounded in the capacity of the moral
agent, that is, in her right, not in the amount of good that her actions produce. Often
overlooked in these accounts are the normative definitions of right, especially as
established here in the Nova Methodus; and yet they form the core concepts from which
the whole of Leibniz’s practical philosophy can be derived.
It will be important to see, then, which elements of Leibniz’s introductory science
of jurisprudence remain and how they develop. As we turn to his Elementa Juris
Naturalis (1671), we will find one important change taking place. Leibniz will again
attempt a science of jurisprudence (called a science of right) based on definitions; he will
even refine its method in important ways; and the moral qualities will remain central.
However, this time the science will focus considerably on the definition of justice, whose
essence is determined to be love. This change is striking, since nowhere in the Nova
Methodus is love mentioned in relation to jurisprudence. But the themes of love and
justice will become fundamental and permanent elements of Leibniz’s practical
philosophy.
166 As Russell holds, for example, in The Philosophy of Leibniz, p. 197.
167 A good example is René Sève, in his Leibniz et l’ecole modern du droit naturel.
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