Liberty Matters

Grotius on the Law of Nature, the Law of Nations, and the Rights of Peace versus the Rights of War


Fernando Tesón makes a good case for each of his readings of Grotius’s doctrine in The Rights of War and Peace.  His readings may indeed be the best readings of the text.  As an amateur reader of Grotius, I have no rational confidence that any of my alternative readings are better.  Nevertheless, with that major caveat, I want to present very briefly a somewhat different vision of Grotius on the Law of Nature and the Law of Nations.  In general I want to highlight features of Grotius’s doctrine that make Grotius an important forerunner of classical-liberal thought.  Here I address only some of the ways in which Grotius is a herald of liberal theory.
1. The Law of Nature
Grotius begins The Rights of War and Peace by saying that, rather than wanting to discuss the Civil Law, which differs from one nation to another, he wants to provide an account of “that Law, which is common to many Nations or Rulers of Nations, whether derived from Nature, or instituted by Divine Commands, or introduced by Custom and Consent…” (I. PD. I).  Tesón reads Grotius to be announcing that he wants to study the Law of Nations and that Grotius takes the Law of Nations to consist of “divine commands, rationally accessible natural law, and human laws.”  I disagree. 
To begin with, the “instituted by Divine Commands” was inserted by Grotius into the 1631 edition – apparently to placate the conservative officials who Grotius hoped would allow him to return to Holland from exile.  Also, there are two distinct bodies of Law that are “common to many Nations or Rulers of nations.”  There is the Law of Nature (which is “derived from Nature”) and there is the Law of Nations (which is “introduced by Custom and Consent”).  So, at the beginning of The Rights of War and Peace, Grotius is saying that he wants to study the Law of Nature and the Law of Nations; moreover, Grotius is not taking the Law of Nature to be a constituent of the Law of Nations. 
In fact, the rest of the opening chapter, “The Preliminary Discourse,” is almost entirely about the Law of Nature (and not the Law of Nations).  For Grotius’s immediate concern is to refute those – like Carneades – who reject the existence of the Law of Nature.[2]   We cannot here attempt to go through the details of this refutation.  We can only note that Grotius holds that the foundation of Carneades’s challenge to the Law of Nature – i.e., to the idea of natural justice – is the proposition that the sole motive for all human action is the promotion of personal advantage.  Grotius attacks this foundation by maintaining that there is a further important motive for human action, viz., “the Desire of Society,” which is “a certain Inclination to live with those of his own Kind, not in any Manner whatsoever, but peaceably, and in a Community regulated according to the best of his Understanding…” (I. PD. VI).
The Desire of Society turns out not to be some generalized empathy but, rather, a disposition to live in accordance with rules, general compliance with which sustains mutually beneficial social order.  We can discover through reason what the rules are that must generally be abided by if a mutually advantageous social order is to exist.  Those rules, discovered by reason in light of the character of human beings and the circumstances of their existence, are the Laws of Nature.  Or, somewhat more specifically, these rules are the Laws of Nature properly and strictly speaking.  There are other rules that are guides to living well that are also part of the Law of Nature, though in an extended and less proper sense.  
The Desire of Society does not displace but, rather, exists alongside of the desire for personal advantage. The Laws of Nature do not displace the “first Duty” of nature which is for “every one to preserve himself in his natural State, to seek after those Things which are agreeable to Nature, and to avert those which are repugnant” (I. II. I.1).  Rather, the Laws of Nature that arise through “the Knowledge of the Conformity of Things with Reason” (I. II. I.2) constrain the pursuit of personal advantage. 
According to Grotius, “Right properly so called” requires,
the Abstaining from that which is another’s, and the Restitution of what we have of another’s or of the Profit we have made by it, the Obligation of fulfilling Promises, the Reparation of a Damage done through our own Default, and the Merit [i.e., justification] of Punishment among Men. [I. PD. VII]Right, properly speaking ... consists in leaving others in quiet Possession of what is already their own, or in doing for them what in Strictness [by way of reparation or agreement] they may demand. [I. PD. X]
So, e.g., Grotius cites Cicero citing Chrysippus to the effect that “There is no Injustice in seeking ones [sic] own advantage; but it is contrary to Equity to take away from another” (I. I. X.4. note 8).
Although the Law of Nature constrains individuals in their pursuit of personal advantage, general compliance with those constraints makes mutually advantageous social interaction possible; moreover, one is admitted to that social interaction on the basis of one’s being compliant with the Law of Nature.  Thus, according to Grotius, compliance with these constraints on how one pursues personal advantage is the key rational strategy for promoting one’s personal advantage.  Thus, in a sense, Grotius seeks to hoist Carneades with his own petard. 
Yet, intriguingly, Grotius seems to argue that individuals will only get the payoff of mutual personal gain if they abide by the Law of Nature constraints for their own sake and not merely for the sake of those personal gains.  “Right has not Interest merely for its End….” and “the Moment we recede from Right, we can depend upon nothing” (I. PD. XXIII). If we did not have the alternative motivation supplied by the Desire of Society, we would never fulfill the desire for personal advantage.
2. The Law of Nature vs. the Law of Nations
The Law of Nations, like the Civil Law of particular nations, is the product of will rather than nature and reason.  In ways that do not seem to me to fit very well with the traditional notion of the Law of Nations (jus gentium), Grotius writes as though the Law of Nations is a code of conduct that governs only the interactions of States or the rulers of States.  It is said to be beneficial to States (or their rulers?) in some way that parallels the Civil Law of a given State being beneficial to that State (or the members of that State?). 
But as the Laws of each State respect the Benefit of that State; so amongst all or most States there might be, and in Fact there are, some Laws agreed on by common Consent, which respect the Advantage not of one Body in particular, but of all in general.  And this is what is called the Law of Nations, when used in Distinction to the Law of Nature. [I, PD. XVIII]
Rather than being a component or aspect of or handmaiden to jus naturale, the Law of Nations appears as an autonomous normative code that at most is slightly constrained by the Law of Nature. 
As Tesón indicates, the Law of Nature specifies the moral default position.  If the Law of Nations does not speak to a matter – e.g., whether prisoners in war may be killed – the Law of Nature stance that war prisoners may not be killed holds.[3]   But if the Law of Nations speaks, its voice will sometimes override or displace the voice of the Law of Nature.  As Tesón points out, according to Grotius, the Law of Nations can make permissible actions that are forbidden by the Law of Nature  (III. IV. XV.1).  So, e.g., the Law of Nations can (and does) make the killing of prisoners in war permissible.  Indeed, the Law of Nations underwrites the whole of the doctrine of “Solemn War” that Grotius lays out in Book III of The Rights of War and Peace.
A State is engaged in Solemn War if (and only if) it publically deliberates about and declares that war against a State or it becomes an “enemy” of another State through the other’s deliberation and declaration.  There is a sense of “just” in which a war is just as long as it is Solemn.  In this sense of “just,” all parties to a declared war are engaged in a just war.  This stands in sharp contrast to the Law of Nature teaching that the only just wars are those conducted to defend against, to attain reparations for, or to punish natural injustices.  Moreover, almost all the Law of Nature prohibitions on how war may be conducted, are overridden or displaced by permissions granted by the Law of Nations to engage in those naturally unjust modes of war-making.  Also, these permissions concerning the conduct of war apply to all the States contesting in a Solemn War – even the State whose cause is unjust in the eyes of the Law of Nature. this [Solemn War] Sense, it is lawful for one Enemy to hurt another, both in Person and Goods, not only for him that makes War on a just Account, and does it within those Bounds which are prescribed by the Law of Nature. . . but on both Sides and without Distinction. . .  And in this Sense we are to take Sallust, By the Laws of War all Things are lawful to the Conqueror. [III. IV. III]
The result, as Tesón says, “is alarming.”  Indeed, it seems that Grotius is eager to emphasize the barbarity of warfare in accordance with the Law of Nations.   And, as Tesón also notes, we then get a remarkable reversal.  For Grotius declares that on reflection, he must “take away from those that make War almost all the Rights, which I may seem to have granted them; which yet in Reality I have not” (III. X. I.1). 
Tesón rightly notes that it is not clear where this leaves Grotius.  In the name of what – honor, charity, virtue, reason – are we to turn away from the dictates of the Law of Nations?  Does this turn involve a general repudiation of the Law of Nations?  If it does, why does Grotius expend so much time and space laying out the dictates of the Law of Nations?
I like the radical hypothesis that Grotius does want us to jettison the Law of Nations as having prescriptive power.  On this hypothesis, Grotius’s attention to the Law of Nations is attention to what he recognizes to be (part of) the positive law but not part of the prescriptively valid law.  For there is a “double Meaning of the Word lawful, the one being taken for that which is really lawful in itself, the other for that which is only lawful externally” (III. X. I.3).  The Law of Nations is to be denied prescriptive force primarily (at least) because it is or has come to be nothing but the Carneades-like sanctioning of unconstrained personal advantage.  And that is precisely what Grotius has set out to rebut and cast aside in the name of the Law of Nature.   (Note that Sallust’s proposition quoted as a summation of the Solemn War doctrine could as readily appear at the outset of Grotius’s treatise as an expression of the Carneadesian view.)  Moreover, the primary values that Grotius invokes in support of his reversal against the Solemn War doctrine are precisely the Law of Nature values of Equity, Justice, and Reason (III. X. I.2 & II.1 & III.1 & VI.1).  So, my wild hypothesis is that in the end, the Rights of Peace (which include the rights of naturally just war and naturally just conduct in war) vanquish the Rights of War.
[2.] The attack on Carneades must be entirely on behalf of the Law of Nature because, according to Grotius, Carneades does not discuss and, hence, does not challenge the Law of Nations (I. PD. XVIII).
[3.] Assuming the Law of Nature is not overridden or displaced within a particular State by the Civil Law (II. II. V).