Stony Brook University

as equity; justice as love) were derived by means of rejecting every insufficient
definition. If ultimately we must remain unsure whether these definitions represent the
ideas of justice in God’s mind or in Plato’s heaven, or whether they have any extramental
reality at all, Leibniz at least provides solid grounds for these ideas as coherent
ideas of justice.
This result should lead us once again to ask, how does a true definition, a true idea
or rule of reason, obligate us to follow it? That is, what makes it morally necessary that
we do not harm another? What binds us to act according to the rules of wise charity? For
Pufendorf and Hobbes, the answer is clear: while reason can inform us regarding the
requirements of sociality and social peace, we are obligated by the externally imposed
fear of punishment, or by the fear of death and the desire to preserve ourselves. 114 For his
part, Leibniz indeed argues that these external reasons function as effective motives for
compliance with the natural law. But these are ultimately not the proper reasons to be
obligated, nor are they the proper sources of obligation. In one way or another, Leibniz
has rejected all of the usual grounds and motives of obligation: pleasure, hope, fear,
conscience, and instinct—none of these provides the right kind of motive, nor can they
tell us with certainty and completeness what our obligations are.
For Leibniz, obligation has two important sources, as it has had from the
beginning. One is the just order. This consists of the true ideas and definitions of right
just and justice. The just order gives us the criteria for judging whether an act is just or
not. The formal reason of justice the Golden Rule is one such criterion. But the second
and most important component is our very capability, our own self-limiting power and
freedom to be moral agents. Pleasure, love, and happiness may motivate us—but
ultimately these motives must be moderated by our own virtue. Thus if we want to be the
moral beings that we are capable of being, we are obligated to motivate ourselves
according to the principles of reason and virtue, which is just to say according to our
moral qualities. As Leibniz had written in 1680:
Therefore right is what we have to act or not to act, a certain power or
moral liberty. Obligation moreover is a moral necessity, without doubt
imposed on those who wish to uphold the name of the good person. 115
The source of obligation lies in the very fact of our moral freedom. That we are endowed
with the moral power to act justly imposes the necessity to act justly. This imposition
cannot be imposed externally, but must be imposed from the inside, from the fact of our
freedom and rationality. Yet obligation is also rooted in the very meaning of just actions,
of just causes, of just conditions. Leibniz thought, as did Plato, Augustine, and others,
that to know the truth is to be moved to follow it. Quoting Cicero, Leibniz in the
Meditation says that to see justice is to be “inflamed” by its beauty and the desire to
pursue it (RM 59). Notoriously, of course, we more often fail to pursue it --“inflamed,”
rather, by the contrary desire for our own good at another’s expense. But such desire is a
mistake. Moral failure is due either to a lack of knowledge of the just, or to a lack of
virtue to employ the knowledge. It is due to a more powerful inclination, an imperfection
114 To speak precisely about this, a fuller account of Pufendorf and Hobbes is obviously required.
115 A.6.4.2850: “Itaque jus quod habemus agendi vel non agendi, est potentia quaedam sive libertas moralis.
Obligatio autem est moralis necessitas, illi nimirum imposita, qui viri boni nomen tueri velit.”
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