






































 ó 


Idealism, Realism, and the Categorical Imperative in Kant's 
Perpetual Peace 

Gordon P. Henderson 
Widener University 

Immanuel Kant's philosophical system is devoted to reconciling the" a11ti­
nomy" between freedom and determmation. 111 Perpetual Peace, tlns becomes 
the related antinomy between morality and politics. This article reinterprets 
Kant's political essays as efforts to reconcile the modern dichot07i1Y in interna­
tional politics between idealism and realism. Kant's application of his famous 
moral rule, the categorical imperative, to the problem of war and peace captures 
the tension between these contradictory approaches tn interl1atinnal relatinl1S. 
The reconciliation he achieves allows contemporary practitioners to be guard­
edly hopeful in their peacemaking efforts. Propon.ents of the" democratic peace" 
thesis, which Kant originated, would do well to control their cnthusiasm; yct 
critics should contain their cynicism. 

This article understands Immanuel Kant's Perpetual Peace1 as a philo­
sophical and practical application of the classic dichotomy between po­
litical idealism and political realism in international relations.2 Philosophi­
cally, Kant defines and seeks to mediate the seeming contradiction be­
tween politics and morality through the application of several formula­
tions of his categorical imperative. In so doing, he insists upon hopefulness 
about the prospects for inorality, and peace in particular, while also warn­
ing that hope must not give rise to paralyzing illusions about the facts of 
political life. In his prescriptions for international political practice, Kant 
draws upon history, political science, and political logic to evaluate the 
philosophical worthiness of familiar types of political action. The result 
of these efforts is an essay that weaves together close analyses of the 
virtues, vices, and inextricable linkages between realism and idealism in 
politics. 

Kant's political thought is a product of his overall philosophical sys­
tem.3 In the Critique of Pure Reason,4 Kant declares a Copernican revolu­
tion in epistemology, in accordance with which he asks "whether we 
may not have more success ... if we suppose that objects must conform to 
our knowledge" (Kant 1929, Bxvi). In other words, what we count as 
knowledge consists of the systematic ordering by the categories of the 
understanding of -empirical and conceptual intuitions. This process of 
ordering is revolutionary because it means that we construct our knowl­
edge and experience rather than have them given to us. The Kantian 
project is to examine and understand the rules of construction and to 
turn away from any effort to know things in themselves. Kant thus un-

1 



dertakes to make explicit the limits of knowing and the possibilities for 
action possessed by rational beings (Kant 1929, Bxxx). 

When presented with the results of the understanding's ordering of 
the data of empirical and conceptual experience, the faculty of pure rea­
son seeks to provide a single organizational scheme for all we know. Rea­
son determines, however, that neither causality nor freedom can be af­
firmed or denied as the controlling principle of what we call experience. 
Kant's solution to this "antinomy of reason" is the adoption of a critical 
standpoint from which reason is constantly checking these tendencies. 
Reason's knowledge of itself therefore becomes as important as its knowl­
edge of experience. As a result, "the doctrine of morality [freedom] and 
the doctrine of nature [causality] may each ... make good its position ... in 
so far as criticism has previously established our unavoidable ignorance 
of things in themselves" (Kant 1929, Bxxix; also see A807 /B835).5 Kant's 
understanding of political experience in general and of war and peace in 
particular can be extrapolated from this epistemological dualism. 

For Kant, political experience, like 0.11 experience, is best understood 
as the systematic ordering of empirical and conceptual intuitions by the 
categories of the understanding. Reason's efforts to find a single organi­
zational scheme by which to explain political experience spark its inter­
est in questions of war and peace. When the understanding apprehends 
all of the attendant suffering, death, and deprivation of war, it considers 
these as no more or less natural phenomena than the passing of a ship 
(Kant 1929, A192/B237). Rather than accept the phenomena of war with 
resignation, reason seeks to locate war within the causal chain, regard­
ing it as both cause and effect. 

Regarding war as effect, reason explores such causes as human na­
ture, the nation-state, and the whole of the state system until, consider­
ing these also as effects, it comes to seek a final original cause. Because of 
its "ignorance of things-in-themselves," however, reason cannot jdentify 
such a cause with certainty. Unable to confirm or deny the necessity of 
war, reason therefore considers the possibility that war is not necessi­
tated by nature (Kant 1929, Bxxiii; Kant 1957, 36, AA 371). 

Reason determines that it must think war unnecessary when it con­
siders war not as effect but as cause. First, reason will come to recognize 
that the attendant deprivations of war, such as fear, hunger, military oc­
cupation, economic collapse, and death, would obstruct reason in its ef­
forts to attain knowledge of nature. Reason is essentially rendered impo­
tent by war. Second, since reason is unable ultimately to complete the 
determination of human beings in the causal chain, it must consider them 
as beings in possession of a self-determining will, that is, as ends in them­
selves. War thus has the additional consequence of obstructing human 
freedom. If humans are required always to act in response to the instru-

2 



11H'lltalities of war, they cannot also exercise treec10m m pursmt of hIgher 
moral ends. Practical reason therefore is also rendered impotent. 

Given these conclusions, the eradication of \'var becomes a moral im­
}wrative. Kant (1937, ] S, AA 356) insists that reason, "from its throne of 
supreme morallegis1ating authority, absolutely condemns war as a legal 
r~'course and makes peace a direct duty." Elsewhere he writes, "morally 
priJchcal reason pronounces in us its irresistible veto: There is to be no 
"var" (Kant 1991, 160, AA 354, emphasis in the original). But while war's 
t'rndication is an impcrntive whose possibility is enhanced by our inabil­
j t ~I to affirm the necessity of war, its achievement is fraught with empiri­
(,11 obstacles. If the end is peace, the means must at least sometimes be 
vv,w. This familiar dichotomy of peace and war makes manifest in the po­
litical realm the dichotomy between freedom and causality in epistemol­
()gy. The resultant political antinomy of idealism and realism is also con­
I ill110US with those of religion and science as well as those of autonomy 
,mel heteronomy. Each of the poles of these antinomies has the force of its 
uwn truth in the struggle between them. As with epistemological antino­
mies, a critical standpoint from which mediation can take place is required. 
I n the various fields of human action, practical reason turns to the cat­
l·gorical imperative as that standpoint. 

Although an extensive explication of the categorical imperative is be­
yond the scope of this article, a few brief remarks will help prepare for 
the analysis of Kant's application of it to the antinomy of idealism and 
realism in international politics. In the Ground'work for l7 Metaphysics of 
l'vlorals, Kant seeks a fundamental principle for moral choice universally 
applicable to all human situations (Sullivan 1989, 149; also see Kant 1956). 
As with critical reason in his epistemology, the categorical imperative 
and the procedures used to derive it are grounded in the limitations and 
possibilities of human practical reason, as Kant understood them. That 
is, we cannot know whether actions that contradict the categorical im­
perative would be appropriate for beings other than ourselves. To Kant, 
thought they are never appropriate for human beings. 

In the FOUlzdatiollS of the Metaphysics of Morals, Kant articulates three 
formulations of the categorical imperative: 

1. Universalizability: I should never act except in such a way that I 
can also will that my maxim should become a universal law (Kant 
1959, 18, AA 402). 

2. Mutual Respect: Act in such a way that you always treat humanity, 
whether in your own person or in the person of any other, never 
simply as a means, but always at the same time as an end (Kant 

.1959,47, AA 429). 
3. PubliCity: Never act in such a way that the maxim of your action could 

not be regarded as legitimate by all parties (Kant 1959, 47, AA 381). 

3 



This article argues that Kant's application of each of these formula­
tions of the categorical imperative to questions of war and peace in Per­
petual Peace mediates between the idea of peace and the realities of in­
ternational politics. 

I 

In his poignantly ironic introduction to the essay, Kant (1957, 3, AA 
343) says that his title is derived from" a satirical inscription [perpetual 
peace] on a Dutch innkeeper's sign upon which a burial ground was 
palnled."6 The image of the graveyard suggesls lhat death 1::; the unly 
sort of perpetual peace likely to result from the failure to construct a 
careful balance of idealism and realism in politics. Realists, who tend to 
accept and even relish the inevitability of war, put themselves and the 
rest of humanity in the grave by applying only force and instrumental 
reason to conflict. Idealists neglect tactics and the verity of force in favor 
of some totalistic vision that lands themselves and humanity, again, in 
the grave. Whether in pursuing knowledge or peace, the uncritical use 
of reason, metaphorically, is death. 

As F. H. Hinsley (1963, 69) notes, the structure of Perpetual Peace takes 
"the form of a treaty ... with a preliminary and definitive articles and a 
seCl"et article .... This tripartite structure includes, first, the conditions to 
be achieved; second, the measures necessary to achieve them; and third, 
the conditions under which it may be hoped that such measures will 
successfully be undertaken. Each of these parts of the essay describes 
political arrangements that derive from the structure of the understand­
ing itself. We begin with the "pJ:eliminary Articles." 

. The "Preliminary Articles" are a catalogue of the concepts constitut­
ing the relations between nations living under perpetual peace. They are 
summed up in the idea that the only peace reason can know and com­
mand is perpetual. A peace treaty is to be "the end of all hostilities" (Kant 
1957,4, AA 33, emphasis mine). To call the seeming peace of a truce or 
ceasefire perpetual is "a dubious pleonasm." As Hinsley (1963, 74) ob­
serves, "[w]hen Kant wrote peace, he meant peace" (emphasis mine). 
Despite the term "preliminary," these articles are not a list of actions whose 
outcome is to be peace. Rather, they describe those relationships between 
and' among nations that for Kant are truly peaceful. Characterized by 
Hinsley (1963, 69) as 1/ a statement of the law of nations as it ought to be," 
the Preliminary Articles insist upon mutual sovereign independence 
among nations while recognizing that their inherent competitiveness will 
drive them into conflict with each other. Tn the tradition of contract theory, 
Kant's Preliminary Articles are the terms to which he believed nations 
would agree if they wanted to coexist and compete peacefully.7 They 
combine a genuine idealism in the commitment to peaceful coexistence 

4 



with a sensible realism that recognizes the strain that competitiveness 
f1l"l'sents. Any treaty whose terms fail to realize any of the Preliminary 
;\ rticles will end in war and is, in fact, no treaty at all. All parties must 
,lgree at the outset that these are to be the outcome of their negotiations 
hdme they can even begin discussing the details of a treaty. The Prelimi-
11<1 ry Articles are the terms of international coexistence to which all na­
tions would agree. 

The six preliminary articles are divided into two parts, each consist­
ing of three provisions. The first three preliminary articles grouped ac­

(Ourding to this division are: 
I. "No treaty of peace shall be held valid in which there is tacitly 

n'st'rved matter for a future war" (Kant 1957, 3, AA 343). 
2. "No state shall by force interfere with the constitution or govern­

l1ll'nt of another state" (Kant 1957, 7, AA 346). 
3. "No state shall, during war, permit such acts ot hostility which 

\Vt )uld make mutual confidence in the subsequent peace impossible: Such 
,lrt' the employment of assassins, poisoners, breach of capitulation, and 
incitement to treason in the opposing state" (Kant 1957, 7, AA 346). 

These three articles express idealism's vision of a genuine peace. Fur­
I h.,1' evidence that Kant understood them this wav is found in his insis-

01 

It'nce that they "hold regardless of circumstances" and that they "de-
Illillld prompt execution" if the peace is to be genuine (Kant 1957,8, AA 
'\47). Hence, these three articles are essential to the internal logic of trea­
li~'s, requiring at a minimum that the genuine intent be to establish peace. 
'I 'rea ties that look to future battles and victories violate the categorical 
Imperative's universalization reqUirement and are little more than veiled 
weapons of war (Gr 18, AA 402). Likewise, interventions in the affairs of 
uther states are inconsistent with the mutual respect requirement of the 
categorical imperative (Gr 47, AA 429). Realist objections to such com­
mitments and forbearance fail to recognize that insecurity in any part of 
Ilw statf' systf'm will tmdprminf' the SPC'll1'ity of 311 stBtes, 

If the resort to war is to be IJ annihilated by the treaty of peace," the 
p<llties to the treaty must be able to trust one another to abide by its 
lL'rms (Kant 1957, 4, AA 343). Even in the midst of war, Kant (1957, 7, AA 
~46-347) argues, it must be assumed that an enemy will not be entirely 
without scruple. For realists such trust is little more than the "sweet 
d ream" of the philosophers; idealism can neverthel ess insist that untrust­
worthy actions contradict the categorical imperative and undermine a 
lasting peace (Kant 1957, 3, AA 343). 

Kant's categorical imperative means that individual acts, whether of 
.) person or a state, define for all actors the terms and boundaries of inter­
,)Ction. Just as the liar loses the short term advantage of lying by being 
told lies in turn, states that deceive to achieve victory in diplomacy or 

5 



conquest will themselves eventually be defeated by deception. Thus li­
ars beget lying, cheaters beget cheating, and warriors beget war. This is 
not to say that all liars, cheaters, and warriors will receive their just deserts. 
Such a proposition could not be independently verified. For Kant, how­
ever, the very discussion or peace presupposes ideahsm f s mSlstence on 
the centrality of trust among nations. Without it there will be a "war of 
extermination" permitting "perpetual peace only in the vast burial ground 
of the human race" (Kant 1957, 8, AA 347). 

Kant focuses in these three articles on the centrality to war of the ten­
dency to resolve conflicts with violence and the assumption that nations 
will disingenuously promise not to do so. By emphasizing the unreflec­
tive character of a thoroughgoing realism, he hints at its ultimate futility 
ill pulilll:~. Realbls, whu Lan never see beyond the conflict at hand, are 
destined to perpetuate and deepen it. Peace treaties founded on exclu­
sively realist assumptions about their meaning are not peace treaties at all. 

The second set of "Preliminary Articles," which critiques ideallsm, 
makes the following points: 

1. "No independent states, large or small, shall come under the domi­
nation of another state by inheritance, exchange, purchase, or donation" 
(Kant 1957, 4, AA 344). 

2. "Standing armies shall in time be tot;:Jlly ahol1shpd" (Kant 1957, 4, 
AA345). 

3. "National debts shall not be contracted with a view to the external 
friction of slaLes" (Kanl 1957, 6, AA 345). 

If the first set of articles must hold immediately and "regardless of 
circumstances," this second set is not quite so constrained. Kant calls 
them J/permissive laws" ot pure reason. The substance of these three ar­
ticles is unimportant to my analysis since they are not immediately to be 
enforced (Kant 1957, 9n, AA348; also see Kant 1957, 37-38,AA372). Each 
of these provisions, like those in the first set of articles, seeks to eliminate 
force as a tool of conflict resolution. Because peacemaking must occur in 
"PrlCP and time, however, the mere assertion by idealists that peace is (or 
should be) at hand is insufficient to assure that it wil1 remain so:'1 

The categorical imperative absolutely prohibits only those actions 
·that would fundamentally undermine any hope of achieving peace. The 
second set of preliminary articles can remain unfulfilled without un­
dermining the integrity of the immediate commitment to the first three 
articles. Nations will have to be prepared to endure the conditions of 
war until all can trust the sincerity of one another's commitment to 
peace. Realism, then, does not violate the universalization formulation 
of the categorical imperative by reserving the resort to arms as a threat 
to maintain the "preliminary" peace. It would be possible, without un­
dermining the prospects for pe(lce, f01' nt'ltlons committed to establish-

6 



Jill-', peace to maintain standing armies long enough to ward off desta­
hilizing developments. Nor does realism violate the mutual respect for­
Illulation: the maintenance of colonies treats other nations as means 
(I lbjects) only in order eventually to treat them as ends. For Kant, the 
\,11 tie of the categorical imperative lies not only in what it prohibits but 
.11.')0 in what the relative formality of its terms permit. Just like criticism 
In l'pistemology, it must be applied carefully to each situation. The trag­
\'dv is that idealism fails to do so: in its enthusiasm for peace, the ab­
c,\'llce of realism's prAemrltir pMipnrp invitps ::Jggression Again, any 
I rl\lty whose founding principles are overly idealistic is not a peace 
t rt',lty at all. 

For Kant, the "Preliminary Articles" contain those principles that rea­
s\ 111 requires as constitutive of a genuine peace. They detail the minimal 
111l1ditions necessary for the flourishing of reason in a global political 
\\)J1text. Kant also uses the Prehmmary Articles to contrast the roles ot 
n'.llism and idealism in politics. Realists focus on instrumental tactics 
t h'lt undermine the fabric of trust essential to a lasting peace. In their 
/('<11 to achieve tactical success in the short term, they compel others to 
d () likewise, thereby reinforcing the suspicions rather than the trust of 
,111. Idealists also undermine their intf'ndpd gAins hom the rreliininary 
f11'i:lCe by acting unreflectively on the idea of trust. Their illusory confi­
dvnce that other states are motivated either by good will or rational cal­
ndation to abstain from aggression leads to a complaisance destined to 
111"0111pt the aggression of realists until they are allIed to "the vast burial 
ground of the human race" (Kant 19578, AA 347). 

Idealists and realists get carried away with themselves. Their obses­
')ion with their own internal principles leads them to unreflective and 
\'ontradictory choices. Especially at critical junctures, both idealists and 
1"l'aJists violate the categorical imperative's requirement that actions be 
universalizable. They unreflectively fall back on a rule of thumb rather 
t hem make a careful assessment of circumstances and consequences. 
Achievement of peace thus becomes a hopeless endeavor. Avoidance of 
\'var becomes a mere luxury afforded only by exhaustion or good luck. 

Acceptance of war's inevitability is not an option for Kant. The atten­
dant deprivations of war, such as fear, hunger, military expense, eco­
nomic collapse, disease, and death would obstruct human achievement 
in knowledge and morality (Kant 195712, AA 351). The requisite collegi­
,11 i ty and high cost of science cannot be sustained during wartime. Worse, 
vvar requires people to act in response to the instrumentalities of war­
f'He. As such they cannot exercise their inherent freedom to obey the 
commands of the categorical imperative. These inhuman consequences 
of war compel reason to seek war's eradication, however quixotic that 
may appear to be. 

7 



The centrality of human freedom to Kant's entire philosophical system 
and the tendency of war to obliterate the possibility of freedom blur the 
distinction between idealism and realism in international politics. Idealism 
is prior and superior to realism in that it derives from the "commands (leges 
praeceptivae) and prohibitions (leges prohibitivae)" of pure reason. Realism, 
on the other hand, derives its authority from these commands and prohibi­
tions. Idealism acts on the positive and negative obligations of what, in the 
Doctrine of Virtue, Kant calls "narrow" duties. Such duties as the command 
to end war or the prohibition against intervention in domestic disputes are 
absolute obligations. By contrast, realism can act only to create and main­
tain the conditions required for the fulfillment of narrow duties. Kant (1991, 
65, 194, AA, 240, 390) refers to these obligations of realism as "wide" duties 
to distinguish them from narrow duties. 9 Whereas narrow duties are dear 
and stand alone, wide duties are derivative, contingent on the circumstances 
in which they are undertaken and bounded by the narrow duties that they 
are positively to achieve or negatively not to contradict. Because idealism 
always acts from narrow duties, often to a fault, realism is always taking its 
cue from the idealist. Yet, realism itself cannot set the standards of action. It 
can only act within the standards established by idealism. Narrow duties 
are the master of wide duties, and idealism is the master of realism. 

The significance of this doctrine of the primacy of the ideal in Kant's 
essay warrants illustration. Imagine caricatures of the idealist and real­
ist. In the political machinations that lead to the outbreak of war, the 
realist patiently, sometimes not so patiently, urges the idealist to make a 
show of strength, to distrust the enemy, and to beware of sinister plots 
and tactics. The idealist stalls for time in anticipation of a final and tri­
umphant "peace is at hand" press conference. When the shooting starts, 
however, the realist orders the idealist aside. War is a military, not a moral 
enterprise, the realist will claim. With that much the idealist will agree, 
while reminding the realist that it is for peace, not perpetual war, that the 
realist's services are engaged. However virile the realist's posture, the 
end of realism is peace, not merely victory. 

Just as the "intuitions" of the first Critique are "blindll without "con­
cepts," so is the realist without the guidance of the idealist (Kant 1929, A 
51/ B 75). War is a non-moral activity. When a battlefield victory is 
achieved, the war is merely redefined, not ended. Neither the categorical 
imperative nor the logic of politics can accept the kind of peace that is 
ar.hieved and maintained by force. Thus, while idealists do not always 
dominate the stage, they are always present in repeating the command, 
which defines the boundaries of a realist's choices: "There is to be no 
war" (Kant 1991, 160, AA 354). Like "empty concepts" that have no em­
pirical referents, however, idealism must be wary of the illusion that be­
cause there is to be no war, there will be none. 

8 



II 

We turn now to Kant's delineabon of the means by which the Prelimi-
11, I rv Articles are to be realized. In the "Definitive Articles for Perpetual 
I \\ICe," Kant describes the practical steps necessary to the achievement 
I. JI ,1 perpetual peace. In formulating the means to this end, he again steers 
d nitical course between idealism nnd re81ism hy trlkin8 ;.:lccount of both 
I Ill' commands of morality and the empirical constraints imposed by poH­
til'S (Kant 1957, 35, AA 370). 

The "Definitive Articles" are introduced with the observation that "[t]he 
'>Llte of peace among men living side by side is not the natural state; the 
Il.ltural state is one of war. This does not always mean open hostilities, 
htl! at least an unceasing threat of war" (Kant 1957 la, AA 348-349). The 
l'stllblishment of peace, contrary to the skepticism of the realists, is both 
morally necessary and empirically possible. Contrary to the dogmatism 
I lithe idealists, however, peace must be established in the natural context 
.1Ild thus prudentially. This duty to establish a peace consistent with both 
I Ill' standards of morality and the constraints of nahm:> le8cls Kant to con­
('Iude that it can be achieved only if relations among people are arranged 
.IS if it is their will to be at peace with one another. They need not actually 
will peace but merely do so externally (juridically) by conforming to laws 
I hilt have them act as though they do. While political idealism is restricted 
I (I sdting as ends the standard of human behavior, political realism must 
devise morally legitimate means, in nature, to accomplish it. 

In view of these considerations, Kant (1957, lOn, AA 350) postulates 
Ihat "[a]l1 men who can reciprocally influence one another must stand 
tinder some civil constitution." That is, in order to assure the law-abiding 
hl'havior necessary to peace, humans must codify right conduct contrac­
IUi:llly. In all contracts, parties must agree on what their relations ought to 
he and then on those means of achieving them that are most consistent 
vvith the moral principles that require those relations. Peace rests upon 
SL'CUrity /I against hostility ... pledged to each by his neighbor." Such 
pledges, howevel~ "can occur only in a civil state"; otherwise, "each may 
treat his neighbor, from whom he demands this security, as an enemy" 

. (Kant 1957,10, AA349). Peace thus requires the establishment of a consti­
tutional context. Without this context, such pledges would be empty and 
('(mld not effectuate the moral requirement for peace. Hence, idealism's 
nptimistic faith in the effectiveness of mutual pledges of friendship is tem­
pered by realism's cautioning on the need for sufficient civil authority to 
,1 void the deterioration of pledges into empty promisE'S. ThE' specific 111E'anS 
devised to achieve that security will differ among different societies as 
well as among different levels of political relations. Each of the three "De­
finitive Articles" describes that constihltion (contract) consistent with these 

9 



requirements that would exist at three levels of political relationship: be­
hveen individuals in a nation, behveen nations of the world, ,mel beh .... ,pell 

individuals considered as world citizens (Kant 1957, 10-11n, AA 350). 
At the level of individuals in a nation, Kant offers the "First Definitive 

Article for Perpetual Peace," the iuea that "The Civll Conslitution of :ev­
ery State Should be Republican." It is "[t]he only constitution which de­
rives from the idea of the original compact, and on which all juridical 
legislation of a people must be based" (Kant 1957, 11, AA 350). Kant's 
enthusiasm for the republican form, which he defines as a separation of 
the executive and legislative powers, stems from the idea that republi­
canism takes the social contract seriously in acknowledging the princi­
pal role of the citizenry in constituting political societies. There can be no 
domestic peace without the contract, and there can be no contract with­
out the participation of the entire society in its construction. The repubH­
can constitution, then, is founded upon the idealist notion that all gov­
ernment derives from the contractual COIl~ellt of Lhe governed. 

Several implications for the treatment of citizens derive from this ide­
alist foundation of the republican constitution. First, each person is en­
titled to a liberty consistent with that of other people. Without this prin­
ciple, there could have been no consent, and no ongoing consent, to the 
social contract. Second; each person is to be subject to one common law, 
without which there could be no ground for agreement in conflicts. Fi­
nally, each person is to be exactly equal to every other person with re­
spect both to the law and to responsibility. Without such equality, there 
could be no true contract because the stronger party would have dic­
tated its terms to the weaker (Kant 1957, 12, AA 349-350). 

Like othert; ill Lhe conLracL Lradition, particularly Rousseau, Kant re­
gards the will of the citizenry as the foundation of authority over it. Politi­
cal authority is never exercised over people without their consent, even 
when they are passive or have never explicitly given it. In giving this con­
sent, they commit themselves to a social rather than private existence. They 
become citizens. The categorical imperative's insistence on autonomy (lib­
erty), universalizability (law), and respect for people (equality) is most 
closely approximated in the republic because it is by definition a society 
co"nstituted by citizens. Consequently, republic;:!ni"m "ie; thf' original basis 
of every form of civil constitution" (Kant 1957, 12, AA 351). 

Although the fundamental idea behind the constitution is that it will 
establish a common law to which all consent and are equally subject, 
Kant is not suggesting that the citizens directly formulate that law in an 
empirical sense. The principal function of the law is to institute the con­
ditions of peace. It must not be construed as an expression of collective 
self-interest. It is a law that expresses the "general will" of the people, to 
which they "would" consent (Kant 1957, 12n, AA 351). In other words, 

10 



II)" republic is not a direct denlOcracy. 
I )emocracy is "necessarily a despotism, because it establishes an ex­

"'lilive in which all ... who are not quite all, decide, and this is a contra­
,Ill lion of the general will with itself and with freedom" (Kant 1957,14, 
\;\ :'52). Direct democracy returns people to a state of war by placing 

',I 1\'l'reignty in the hands of the majority. Kant thus dismisses the idealist 
\\ Illl might mistake him as saying that political legitimacy requires the 
"Illpirical consent of people who, by nature, are self-interested. To the 
(I lillrary, it requires the consent of reason as expressed by rational beings 
II]J'( lugh the general will. With a nod toward the realists, Kant further 
(" ,..;c'rves that the law can be effective even in thfl conduct of /I a race of 
d,'vils," as long as the state is organized well and the citizens are intelll­
:,~I 'nl enough to follow its incentives. Specifically, 

"the powers of each selfish inclination are so arranged in oppo­
si tion that one moderates or destroys the ruinous effects of the 
other. The consequence for reason is the same as if none of [these 
inclinations] existed, and man is forced to be a good citizen even 
if not a morally good man." (Kant 1957, 30, AA 366) 

Kant's republic, then, is governed for and through the people but not 
'll'cL'ssarily by them. It would be ruled by a preferably small number of 
1i'11rI>sentrltivflS, fllthflr an aristocracy or a monarchy who would frame 
1,)\vS that facilitate the orderly clash of interests. On the one hand, Kant's 
!'I ,,]1 ism warns that the larger the number of rulers (such as collective 
Illonarchies, corporatist aristocracies, or representative democracies), he 
,~~rl',lter is the likely influence of self-interest (Kant 1957, 15, AA 353). On 
Ilw other hand, realism also warns that however small the number of 
n IIL'rs, they might become just as despotic as democracies by ruling in 
Ilwi r self-interest. Nevertheless, "it is at least possible for [aristocracies 
,1Ild monarchies] to assume a mode of government conforming to the 
"pi rit of a representative system/' while it is impossible in democracies 
"since everyone wishes to be master" (Kant 1957, 14, AA 353). Idealism 
pft'vails in the insistence that a citizen's right to pursue self-interest is 
lundamental to the good constitution, whereas realism points away from 
,h'l1locracy and is only guardedly optimistic about the republican poten­
I i,ll of monarchy and aristocracy. Ultimately, the republican mode of gov­
ernment is to harness the selfish inclination against war. 

The "Second Definitive Article for Perpetual Peace," that "The Law of 
1\J(ltions Shall be Founded on a Federation of Free States," depends upon 
l he first article. According to Kant, it is not only conflict among them­
sl'lves as individuals that inclines people to form themselves into a state 
I If ordered liberty. "Even if a people were not forced by internal discord 
[n submit to public laws," he writes, "war would compel them to do so" 

11 



(Kant 1957, 29, AA 365). Thev will inevitably find themselves surrounded . . 
and threatened by individual states in the same way they are threatened 
by other individuals. The need to defend against this threat requires the 
formation of a state in which selfish inclinations can be prevented from 
interfering with collective self-defense. Domestic peace, albeit among 
"uevlb," l~ e~~elllidllu llLlenldliollal peace, which is likewise essenliallo 
the fruits of domestic peace. This continuum of domestic and interna­
tional political order means that the two are not much different from 
each other and that idealism and realism will occupy the same positions 
in framing an international peace as they do at the domestic level. 

According to Kant, citizens of republics will be disinclined to go to 
war because the true general will, expressed by citizens or their repre­
sentatives, would not consent to a declaration of war. "[N]othing is more 
natural," he writes, than that people would be livery cautious in com­
mencing such a poor game, decreeing for themselves all the calamities of 
war" (Kant 1957, 12, AA 351). Even if people are naturally inclined to­
ward war when they dre uut~iue the ~tdle, lhey would nol consenllo il if 
their liberty under a republican constitution, if not their own morally 
developed individual wills, prohibits it (Kant 1957, 17, AA 355). The fea­
ture of republics that inclines them to peace thus lies in their constitu­
tion. A republic is a state in which the citizenry has a direct stake. Its 
existence is dependent upon their individual as well as collective wills 
and is at least implicitly formed and maintained by them for the sake of 
their liberty to pursue their particular interests. For Kant, the republican 
stl'ltp has pprsona lity. Tts citizens will only reluctantly go to war, and then 
only to preserve their freedom from outside invasion. 

The personality of republican states also makes untenable the achieve­
ment of global peace by means of a world republic. An idealist might 
advocate a world republic on the ground that all peoples could live to­
gether under one global personality. Realists might advocate a world 
republic or government as the only way to prevent wars, skeptically sub­
stituting a powerful central regime for the hope that republics would 
refrain from war. Yet republics, having been formed by the will of a spe­
cific group of people, will be reluctant to surrender the autonomy achieved 
in that act of will to the will of other peoples. Thus, while the republican 
personality might give the idealist cause for hope, the realist wlll pm­

phasize that "personalities," however much inclined they are toward com­
munity over conflict, will nevertheless insist on their autonomy. 

These cunsideralions necessitate the federation of free states. Although 
conflicts inevitably will arise among their differing personalities, the fed­
eration preserves the autonomy of each member state. Republican states, 
animated by their individual personalities and reluctant to go to war 
unnecessarily, are mindful of the need for a system of law to provide 

12 



\111 iL,ctive security that is least threatening to individual autonomy. While 
lllld i ng such law in the federation, they no more attribute a truly good 
\\ i II to the participant states than they do to the citizens of the republic. 
I .i kc the republic, the federation is necessarily a weak alternative never­
tlll'il'ss dictated by reason. It can come about when "a powerful and en­
lightened people" makes itself a republic, thereby inclining itself to per­
Jld UC11 peace, and in thp intel"!?st of extending its freedorn., coming to serve 
.1'-; ,1 "fulcrum to the federation" (Kant 1957, 18-19, AA 356). At best, it 
\ \' i II become" only the negative surrogate of an alliance which averts war, 
"l1d ures, spreads, and holds back the stream of Lhose hosLile pdssiuns 
which fear the law, though such an alliance is in constant peril of their 
I 1 I'l'<l king loose" (Kant 1957, 20, AA 357). 

'rhe federation is a pragmatic response to the imperative of perpetual 
jlt'.1Ce. It meets the command of the categorical imperative to undertake 
.Jl"[iulls that are universalizable but not totalistic. The categorical impera­
lin' prohibits actions that would lead directly to war but permits actions 
111.1l, while perhaps not ideal, are benign. States can form themselves into a 
ft'Licration for the purpose of estt'lhlishin8 a frrtmework for peace without 
·,.lnificing their autonomy as personalities. Were it to be otherwise, realists 
\\'lluld note, individual states would seek ways to break out of the federa­
II< >11. Idealism obtains its de facto peace, whereas realism restrains the incli-
11.1lion toward a global autarchy that would ultimately prove fatal. 

'rhe federation is also consistent with the mutual respect formulation 
lli the categorical imperative. The formation of a league among states, 
whose relationships are defined by a law they collectively choose, imple­
ll11'nts the requirement that they treat each other as ends. That they may 
II )ntinue to regard each other's actions with suspicion and maintain their 
11.1 tional identity is consistent with the permission they have to treat each 
nlher as means. For idealism, states must treat each other as ends; for 
I"l'<llism, they need not do so blindly at their own expense. 

The third "Definitive Article" states: "The law of world citizenship 
:-;klll be limited to conditions of universal hospitality" (Kant 1957, 20, AA 
\:-17). Quite simply, all people possess "a right of temporary sojourn, a 
right to associate ... by virtue of their common possession of the surface 
\)1' the earth" (Kant 1957, 21, AA 358). Idealism's commands here, as they 
s\) often are, are double-edged. People as individuals have the right to 
I ravel to other places controlled by other states. Merely occupying a piece 
\)f ground does not entitle one people to exclude others. Yet, just as physi­
\',11 possession does not grant exclusive title, the common possession of 
I':,lrth does not permit invasion, pillage, and colonialism. If all stC'ltf'S actpd 
in accordance with these limiting principles, no state could entirely iso­
Illte itself or intrude so completely on another as to undermine the latter's 
self-identity. The integrity of the state as personality is as dependent upon 

13 



contact with other states as on security against excessive intrusion. 
As always, idealism's standards cannot be met by idealist means. 

Rather, Kant suggests that the principal form of the contact between states 
is commercial. One need not rely on idealist notions of cosmopolitan sen­
sibility that bring "the human race ... closer and closer to a constitution 
establishing world citizenship" (Kant 1957, 21, AA358). The profit motive 
will be increasingly sufficient to reduce the likelihood that violence will 
be used to resolve the inevitable conflicts among human societies. Just as 
good citizenship at the domestic level depends more on or8;:)ni7,ation than 
on virtue, a global "kingdom of ends"10 depends more on the invisible 
hand of the marketplace than on the triumph of good over evil. 

The "Definitive Articles," centrally located in the essay~ are also the 
centerpiece of its conceptual composition. They reject in turn those real­
ist assertions of the intractability of war: that human nature is warlike; 
that nation-states, by definition, cannot forbear war; and that mutual un­
derstanding and "hospitality" between peoples are restrained by and 
can thus never overcome the previous two assertions. Each assertion, 
considered as a matter of realistic thinking, stands refuted on the ground 
of the irrefutability, and hence possibility~ of the commands of idealism. 

The "DefinHive Artide~" reject the ideali~t notion that merely assert­
ing the possibility of political right guarantees its success. They do so by 
insisting that while the appropriate steps toward peace must be consis­
tent with the categorical imperative, they must nevertheless occur in space 
and time and thus be consistent with political prudence. National gov­
ernments cannot be pure democracies. International organization cannot 
be world government. World citizenship does not obliterate nationalism. 

In these ways, the "Definitive Articles" comprise a practical formula 
for the "establishment" of the peace described in the "Preliminary Ar­
ticles." They demand the fulfillment of both narrow and wide duties. The 
categorical imperative is intended to promote the same critical standpoint 
in practical affairs that is required in epistemology. The attainment of peace 
thus requires a "political wisdom" that critically restrains the realist and 
idealist extremes to which each is led by the proximity and vanity of its 
perspective (Kant 1929, A475, B503). Only in this way can reason fuWIl its 
"architectonic interest" - indeed, its very survival by escaping the 
peace of the innkeeper's sign (Kant 1929, A474-475, B502-503). Whether 
nations, their leaders, or their citizens would sacrifice their own self-in­
terest to the longer-term vision of a lasting peace begs the question of the 
prospects for peace and the federation that is to maintain it. If there is no 
hope of humanity taking such actions, there is little point in discussing 
the Preliminary and Definitive Articles other than, perhaps, to produce a 
kind of anthropology of political ideas. Since Kant disdained such idle 
speculation, his response to the question of hope warrants close scrutiny. 

14 



In 

In order to fathom and evaluate Kant's response to this important ques­
tion of hope, we return to the categorical irnperative, \l\1h1Ch is the fruit of 
Kant's search for a fundamental moral principle applicable to all human 
situations (Sullivan 1989, 149). In addition to serving as a guide for ac­
tion, the categorical imperative is also the expression of the first proof 
that there is hope for peace. In the Critique ~f Pure Reason, Kant foreshad­
ows his later work in practical philosophy. He assumes lhal"there really 
are pure moral laws which determine, completely a priori (without re­
gard to empirical motives, that is, to happiness) what is and is not to be 
done/' and that "since reason commands that such actions should take 
place, it must be possible for them to take place" (Kant 1929, A807, B835). 
Here and in his ethical works, Kant argues both that there is a moral law 
and that, jf it is to be taken seriously, it entails the concept of duty. 

This theme is continued in Perpetual Peace: 

Taken objectively, morality is in itself practical, being the to­
tality of unconditionally mandatory laws according to which we 
ought to act. It would obviously be absurd, after granting au­
thority to the concept of duty, to pretend that we cannot do our 
duty .... Consequently, there can be no conflict of politics as a 
practical doctrine of right, with ethics, as a theoretical doctrine 
of right. (Kant 1957, 35, AA 370) 

As Kant (1957, 46, AA 380) puts it, the first justification for hope is that 
"pure principles of right have objective reality." The vision of peace im­
plicit in idealism and specified in the Preliminary Articles is actual. It there­
fore entails the duty obey it. Yet, the mere assertion that the idea of per­
petual peace is actual, that we have a duty to fulfill it, and that that duty 
implies possibility is insufficient proof of hope that we might actually do 
so. For realism, this would be the height of idealisnl's folly. No ruler can be 
expected to make the sacrificial leap of faith entailed by such a duty. 

In order to strengthen his position on this issue, Kant offers a political 
formulation of the categorical imperative: "All actions relating to the right 
of other men are unjust if their maxim is not consistent with publicity" 
(Kant 1957, 47, AA 381). This formulation asks whether an action with 
political consequences is capable ot passing public scrutiny. Secret machi­
nations, policies, and agendas are suspect by definition. Publicity requires 
full disclosure. If any attributes of any action or agreement could not 
survive unless hidden from those affected, then the agreement or action 
must be discarded. 

The publicity formulation restates the universalization formulation 
of the categorical imperative in empirical language and thereby serves 

15 



as the vehicle by which ought becomes is in politics. More precisely, the 
publicity requirement sets a standard for politics and provides a con­
crete way to measure its attainment. As discussed by Kant in the Prelimi­
nary Articles, the most important component of peaceful politics is trust. 
Publicity requires that parties to an agreement promise not to undercut 
it by secret decisions. It is simply the rule of non-contradiction; where 
there is deception, there is no real agreement; and where there is no agree­
ment, there can be no peace. 

l{ealists will be skeptical of this argument. Even though there is a prac­
tical formula for measuring the conformity of politics with the moral law, 
there is still no apparent incentive for rulers or the public to apply it. Kant 
(1957,33-34, AA 368-369) offers an ironic response in the "Secret Article 
for Perpetual Peace." He begins by reemphasizing that secret clauses in 
contracts, especially those having to do with political society, are a funda­
mental violation of the law of non-contradiction. He then proceeds to the 
ironic exception to this rule: rulers may keep secret from their respective 
publics and each other that they listen to the advice of philosophers. 

This exception is made for several reasons. First, philosophers are the 
bearers of the moral law because they possess and articulate "the un­
trammeled judgment of reason." Since they are "by nature incapable of 
plotting and lobbying," they can be trusted to speak candidly. Second, 
leaders are expected to strike the pose of might, not right, to their en­
emies. It would be "humiliating to the legislative authority of a state" if 
its susceptibility to the influence of philosophers were known by its en­
f'mif'f:l (K~nt 19,,7, .'i:i, A A :ifiR)_ Thirn, philosophers should not be given 
any more than a hearing because to give them power of influence would 
"inevitably" corrupt their judgment. Fourth, as a practical matter, this pro­
viso is not to suggest that "kings or kinglike peoples who rule themselves" 
ought to become philosophers, for their task is governing, not contem­
plation. Yet rulers, whether in monarchy or republics, should always al­
low philosophers to speak because their opinions are "indispensable to 
the enlightenment of the business of government." In any case, to censor 
philosophers is to acknowledge their influence (Kant 1957, 34, AA 369). 

Hope for peace is strengthened by the "Secret Article" because phi­
losophers are the voice of idealists, the keepers of the moral law. Since 
the possibility of their influence is to be kept secret,. thf'rf' is no rf'ClSOn to 
silence them and the idea of peace they articulate. Thus, says Kant (1957, 
46, AA 380), "the moral principle in man is never extinguished." Like­
wise, idealists are not to have the influence that would lead to a danger­
ous neglect of the practical matters so central to statesmanship. Leaders 
need not be idealists but may concentrate on the realist task assigned to 
them. Nevertheless, their actions will always occur against the backdrop 
of the command, "There shall be no war" (Kant 1991, 160, AA 354). 

16 



A derivative significance of the Articie" in Pernetual Peace is '-, J 

its permissiveness. The publicity requirement of the cMpf:;nricnl irnp(~rPl-
tive is not absolute with regard to philosophers. Just as actions that do not 
contradict the universalization or mutual respect formulations of the cat­
egorical imperative are permitted, so too are actions that do not directly 
contradict publicity. For instance, standing armies can be maintained with­
out violating universalization; states within a federation can still be wary 
of member states without violating mutual respect; and weapons devel­
opment, lend-lease plans, and even doomsday planning could remain se­
cret without violating the rule of publicity. The categorical imperative lays 
down boundaries to action, narrow duties, which are absolute. Yet, there 
is wide latitude in practice by which to meet these obligations. 

On the question of Ilnpf' fm Pf'l'lCf'r Kl'lnt to this point hl'l5: 1) declared 
the objectivity of the moral1aw that requires peace; 2) established a con­
crete means for measuring political conformity to the categorical impera­
tive (publicity); 3) identified a class of people (philosophers) who articu­
late that law; and 4) rendered it unnecessary for leaders to acknowledge 
that they are guided by morality. He has not, however, answered the ques­
tion. After all, even if leaders were to listen to and act upon the advice of 
philosophers, they might not meet with enough success to sustain that 
course of action. In other words, virtuous ends do not guarantee success­
ful means. According to the "First Supplement: On the Guarantee of Per­
petual Peace," nature, not human action, provides this guarantee. 

In this section, Kant posits nature directing humanity toward peace 
in spite of itself. In particular, those hostile inclinations that lead people 
to war actually serve to draw them closer to the idea of peace by high­
lighting the costs of war. Differences of "language and religion" serve to 
prevent attempts at world government while also increasing the pro­
pensity to engage in commerce which is "incompatible with war" (Kant 
1957,31-32, AA 367-368). 

Although Kant (1957, 30-31/ AA 366-367) is careful not to attribute to 
nature "the profound wisdom of a higher cause" or "a cunning contriv­
ance," he might as well have done so, for he cannot resist exclaiming that 
I/[nJature inexorably wills that the right should finally triumph," even if 
not by attaining "the moral improvement of men." Nature "guarantees 
perpetual peace by the mechanism of human passions." Yet, II she does 
not do so with sufficient certainty for us to predict the future in any theo­
retical sense," even though the hunger for hope might make our empiri­
cal observations of human interrelations appear to confirm that this is 
nature's design. It therefore remains our duty to work for peace con­
sciously (Kant 1957, 32, AA 368). 

The question of hope is again a question of human volition: hope for 
peace depends upon the willingness of human beings to pursue peace. 

17 



K;:mt's ;:mSWPl" rpljes upon the practical idea that individual persoll.alities 
must be combined into a collective personality. Individuals will not will 
peace. But if merged into a collective, they acquire a social personality 
that can will peace for them. As a praclicalrlLaller, KdJlt is careful to note 
that this collective personality can only be formed by means of coercion. 
One "legislator" will have to form a nation from "a horde of savages" 
(Kant 1957, 36, AA 371). This being so, the legislator will be unwilling to 
permit them to form their own constitution. Because rule thus begins 
with force, it will be exercised tyrannically. Hope for peace continues to 
rest upon volition, albeit of the leadership of a single nation. 

The leader of a nation founded in coercion must, of course, maintain 
the collective through coercion. It becomes difficult to see how leaders 
and their policies can be anything but realist. A leader might err as a 
IJdespotic moralist," prematurely acting on idealist principles without 
giving due attention to praclical cOHslrainb. Nundhdess, time and ex­
perience will cause leaders and their successors to take a more realistic 
course (Kant 1957, 38-39, AA 373). On the other hand, rulers who cannot 
forget that nations are formed by force are unlikely to shape policy in 
accordance with anything other than practical experience. As this is likely 
always to teach them cynicism about human nature, the idea of peace, 
let alone its deliberate pursuit, will not constitute an influence over policy. 
Unlike the "despotic moralist," the "political moralist" will never "learn" 
from experience but will instead be guided by it, forgetting that the es­
tablishment of a collectivity, albeit by force, merely fulfills a wide duty 
on the way to fulfillment of the narrow duty toward peace. 

Kant is confident that political moralists, the epiLolIle vf realbm in 
politics, cannot continue indefinitely. Their maxims are transparent, self- . 
contradictory; and ultimately self-destructive (Kant 1957, 40, 45, AA 374-
5, 379). Their arrogance is impossible to sustain because of the variety, 
number, and complexity of information they must use in their calcula­
tions (Kant 1957, 43, AA 377). Even if they mean to achieve peace, as 
most realists claim to do, they are more likely to be ensnared by their 
own machinations. The tragedy of realism for a people is that its demise 
and whatever lessons it has to tf'8ch arp a long time in coming. 

Better, says Kant, that rulers adopt "political wisdom" as their guide. 
While a course of action must be thoroughly grounded in the intricacies 
of empirical experience, no action should be taken that cannot fit the 
standard of publicity. Prudent maxims that also conform to the political 
formulation of the categorical imperative will achieve peace more effec­
tively than either idealism or realism. The principle of publicity defines 
that narrow duty in the fulfillment of which leaders may choose any 
number of pragmatic courses. In times of intensely confused conflict, the 
best course would be to take small, sometimes seemingly cold-hearted 

18 



steps mure Lun::-;btellt I'vitJ t d l11Uloughgoing reallsm. Al oLher limes, com­

merce or war-weariness may make possible grander idealist steps to­
ward peace, such as the establishment of international institutions and 
agreements. The wisdom of experience tempered by a focus on the ad­
vancement toward peace would determine the extent of action under 
either scenario, bounded always by the requirement of publicity. 

Kant's response to the question of hope rests ultimately on his provi­
sion of a rule, publicity, by which realism and idealism might be bal­
anced in politics. He seeks both empirical and moral grounds for guar­
anteeing that peace can, and will, be achieved. That guarantee, however, 
is always dependent upon human volition. Knowledge of the moral im­
perative does not assure that the duty will be met; philu::;uphert::i mighL 
not be permitted to keep the idea alive; and rulers might not take up 
their duties. Hope for peace is embodied in its availability, not its neces­
sity. The objective reality of the idea of perpetual peace simply does not 
guarantee its practical manifestation. 

IV 

Kant's failure to answer with finality the question of whether there is 
hope for perpetual peace is wholly consistent with his "critical" philoso­
phy. Moreovel~ this failure captures the message of Perpetllal Peace for 
practitioners and theorists of international politics alike. The antinomy 
between idealism and realit::>m it::> dIIlelldble only Lo mediallon, not resolu­
tion. Like antinomies of knowledge (freedom and causality), ethics (au­
tonomy and heteronomy), and religion (God and nature), so too do hu­
man understanding and pure reason leave us, at best, with an orderly 
untidiness. The order results from criticism's restraint of the poles of each 
antinomy. The untidiness follows because criticism is an ongoing pro­
cess: new data, new situations, new beliefs, and new interests reinvigo­
rate the antinomies of knowledge, ethics, religion; and politics. There 
seems to be no guarantee of perpetucd perlCf' 

Even though he genuinely despises the cruel brutality and irrational­
ity of the practice of politics at all levels of governance, Kant never offers 
mure than spe<.:ulative hupe fur all end to it. To do otherwise would go 
well beyond the boundaries of his philosophical system. Instead, he of­
fers hopefulness grounded in the establishment of liberal (republican) 
polities and their international parallel, the Federation. Liberalism's chief 
virtue is its institutionalization of a critical perspective sufficient to re­
strain the darkness of realist despair and the blinding light of idealist 
hubris. Its openness and intelligence make any long-term commitment 
to either polarity nearly impossible and minimize any historically sig­
nificant damage stemming from such commitments. Of course, either 
idealism or realism, separately or in tragic combination, can return to 

19 



wreak their special havoc on a global scale at any time. Nevertheless, 
Kant urges us to be hopeful that such episodes will be brief, survivable, 
and inCrl:>;1c:;ine1y infrequent. As the number of liberal regimes increases, 
he hypothesizes, the less likely will be violent outbreaks among them. 
Nature will "accomplish what reason could have suggested ... without 
so much sad experience" (Kant 1949, 120). 

Kant's hypotheses have been put to the test by history and the rela­
tively sophisticated tools of social scientific analysis that emerged after 
World War II. Under the heading of the "Democratic Peace Debate," schol­
ars of international politics have examined the empirical evidence to 
determine whether, and if so, why, liberal democracies pursue nonvio­
lent means of resolving the conflicts that arise among them. The demo­
cratic peace thesis, initially framed by Doyle (1983), has sparked much 
schoblrly dpbate l1 Yet, the western democracies, led by the United States, 
have pronounced a renewed commitment to pro-democratic policies on 
the presupposition that democracies (the republican form) are inclined 
to peace at least with one another. 

Based upon a survey of wars over a two hundred year period, Doyle 
(1983, 213) concludes that "even though liberal states have become in­
volved in numerous wars with non-liberal states, constitutionally secure 
liberal states have yet to engage in war with one another." He takes a 
Kantian approach to explain his claim by looking to the internal charac­
ter of modern liberal democracy. Such regimes, he says, possess a com­
mitment to mutual non-intervention, regular rotation in office, and sta­
bilizing internal constitunonalstructures such as separation of powers. 
Anticipating realist criticism, Doyle is careful to note that these regimes 
do not hesitate to go to war with non-democratic states when it is in their 
interest to do so. Still, he insists that realism cannot deny his findings. 
Even if peace among democratic states is little more than "prudent di­
plomacy," this II cannot account for more than a century and a half of 
peace among independent liberal states, many of which have crowded 
one another in the center of Europe" (Doyle 1983,213). 

Dixon (1994) takes as a given that democracies are as likely to become 
engaged in international conflict as are non-democracies, but he also rec­
ognizes that they are more likely to settle serious disputes with one an­
other before military hostilities develop."In his "search for a satisfactory 
explanation," he turns to the procedural norms he finds to typify democra­
cies. "The particular bundle of norms to which he attributes the tendency of 
democracies to seek peaceful settlements to their disputes is "bounded 
competition.""In the management of their own highly competitive internal 
affairs (elections and markets, for example), democracies develop habits 
and skills at cont1ict resolution that are then carried over into their rela­
tions with other similarly constituted states."As a result, when democra-

20 



cies do confront other democracies, "these shared norms of bounded com­
petition will provide a mutual basis for contingent consent, suggesting that 
dispules between democracies should evolve somewhat differently than 
do disputes between states not sharing these norms" (Dixon 1994, 17). 

Of the many realist critiques of the democratic peace thesis, that of 
Farber and Gowa (1995) is typical."Doyle's evidence, they argue, can be 
explained as prudence at work; democratic norms are not necessarily 
the reason for the apparent pacific union among liberal democracies." 
Since peaceful conflict resolution usually perpetuates the status quo to 
the advantage of winners, they are likely publicly to celebrate such out­
comes in terms that de-emphasize self-interest. Moreover, negotiated 
settlements are less expensive than wars, especially when high-stakes 
international commerce is involved." If liberal democracies are so peace 
lovillt" lItey ask, why are lhey willing to go to war with undemocratic 
states?" They also question the data itself." Besides claiming that the pa­
cific union among liberal democracies existed mainly during the Cold 
"Var era, they make the Hobbesian point that the threat of war is suffi­
cient to characterize a conflict as war." Thus, they emphasize incidents 
of "militarized interstate disputes." 

In another variation of the realist critique, Mansfield and Snyder (1995) 
reconfigure the data to distinguish between mature and emel"ging de­
mocracies. The latter, they Claim, lack the institutional stability required 
to restrain the war-making inclinations of those elite interests and par­
ties that stand to lose in democratization. liThe ferocity of elite power 
struggles nlakes ernerging democracies particularly dangerous." Promot­
ing democracy around the world in the name of the democratic peace 
could produce another of those ironies so typical of politics: "idealism's 
faith in democracy is turned on its head by the instability of 
democratization." According to another of realism's proponents, demo­
cratic peace theory is "dangerous" in that its "zone of peace is a peace of 
illusions. There is no evidence that democracy at the unit level negates 
the structural effects of anarchy at the level of the international political 
system"(T .rlyne 1994, 4R; rll!=>() see Waltz 19.59). Elsewhere he observes that 
"the democratic-peace theory blinds us to the fact that what really counts 
in international politics is power." Capturing Kant's own warnings in 
the preliminary articles against idealism's tendency to be too trusting 
too quickly, another realist concludes that" certain states that we don't 
worry about now as threats to our security, because they are democra­
cies, may in fact prove to be real threats down the line. If we have ideo­
logical blinders on, we may not see that" (Shea 1996, A7). 

More recent work on the democratic peace has focused not on whether, 
but on why, democracies do not go to war with one another./lBruce Buena 
De Mesquita, James D. Morrow, Randolph M. Siverson, and Alistair Smith 

21 



(1999, 791) declare that ithe empirical evidence for this claim is quite 
strong." While they emphasize the claim of Kant and Doyle that domes­
tic political institutions matter in foreign policy choice (deciding whether 
to go to war, for example), they reject, along with normative explana­
tions, those institutional explanations that rely on the public's restraint 
of political leaders in matters of war and peace. Their alternative expla­
nation, based on a realism grounded in game theory, portrays political 
leaders who respond to the institutional incentives of liberal democra­
cies much like the "intelligent devils" in Kant's Perpetual Peace (Kant 1957, 
3D, AA 366). With their hold on power tied to public approval through 
elections, such leaders choose only wars they can win, and they make an 
all-out effort to do so. Since democratic leaders can attribute this quality 
to their counterparts in other liberal democracies, they are less likely to 
bear the expense and risk of going to war with each other. 

This latter approach to the question of the democratic peace is consis­
tent with Kant's. Although the reluctance of democratic states to war 
with one another is based upon "prudent diplomacy," the end of peace 
is achieved in its ideal form. The institutional arrangements of liberal 
democracies make them better suited than non-democratic states to peace­
ful international relations. They are also more suited to global trade and 
intercourse than arc non democratic states. Finally, their internal com­
mitment to a constitution that promotes individual freedom and equa]­
ity addresses Kant's First Definitive Article. 

Kant would undoubtedly be gratified to know that modern political 
science has had such confidence in its empirical verification of his thesis. 
Yet, he would also warn that this affirmation should not be allowed to 
feed an idealism that might be inclined to advocate democratization with­
out concern for the dangers cited by Mansfield and Snyder (1995). In­
deed, the democratic peace may prove to be only a western phenom­
enon, as the personalities of emerging nations may not favor democracy. 
Nor would Kant dismiss Layne's warning that friends may not always 
be friends. The categorical imperative's insjstence that we treat others 
always as ends and never as means only permits treating others as means. 
The v~ry existence of a state system consisting of independent nations 
that can be united, at best, within a federation is indicative of the poten­
tial for any of those states to become warriors against their confederates. 

For Kant, the goal must always be to strengthen the prospects for a 
lasting peace. Neither idealism nor realism must be allowed to dominate 
foreign policy. A careful, critical balance must be struck between them so 
as "to prevent precipitation which might injure the goal striven for" (Kant 
1957, 8, AA 347). In other words, modern states should not allow their 
confidence in the democratic peace to blind them to the verities of inter­
national relations. Likcwisc, they must not allow their skepticism to deny 

22 



<.11111 ulluerminewhal conten,porary political science has affirmed. The 

ideological passions of idealism and the cold calculations of realism are 
the necessary means to the end of achieving peace. Kant (1957, 46, AA 
380) concludes, Ii All politics must bend its knee before the nght." 

Notes 

1. Citations of Kant's work in this article include references to volume 8 of 
Kant's gesam111eite Schriftell (28 vols., Berlin and Leipzig: Walter de Gruyter & 
Co., 1904ff.), the" Academy Edition," which I abbreviate as AA. 

2. The classic statement of the distinction between "utopian" and "realist" theo­
ries of international politics is found in Carr (1939). Also see Waltz (1959). Doyle 
(19R:i) treats realism at length in the context of his discussion of the democratic 
peace. For a critical treatment of idealism as "Wilsonianism," see Layne (1994). 

3. O'Neill (1986, 524) observes that Kant's "entire critical enterprise has a cer­
tain political character." Also see Arendt (1982), Friedrich (1948), Humphrey 
(1983), Laursen (1986), Mulholland (1987), OiNeil1 (1989), Reiss (1970), Riley (1983), 
and Saner (1973). 

4. Citations of Kant's Critique of Pure Reason in this arbcle include references 
to both the A and B editions. 

5. Kant's passion for his subject and for the significance of the nature / free­
dom antinomy is movingly expressed in the following metaphor from The Cri­
tique of Practical Reason: "Two things fill the mind with ever new and increasing 
admiration and awe, the oftener and more steadily we reflect on them: the starry 
heavens above me and the moral law within me" (Kant 1956, 166, AA 161). 

6. For an interesting discussion attributing the "innkeeper's sign" metaphor 
to the work of Kant's predecessor, Leibniz, see Riley (1983, 122). 

7. For an extensive discussion of Kant as contract theorist, see Riley (1983). 
8. This would be the political equivalent ot the metaphYSical pnnclple that 

"an event which should follow upon an empty time, that is, a coming to be pre­
ceded by no state of things, is as little capable of being apprehended as empty 
time itself" (Kant 1929, A 192, B237). 

9. For a discussion, see SulUvan (1989, 51-54). 
10. The reference here to a "kingdom of ends" is intended to emphaSize a 

critical understanding of Kant's political theury. A!:> is ilue throughout his prac­

tical philosophy, Kant wants human action directed toward attaining an ideal 
community. This, however, is the ideal for Kant, and his perspective requires 
that it be carefully balanced a~aim;t whalls possible. There cannot be any com­
promise on what the goal of human action is to be, in this case perpetual peace 
among nations. Yet, the idea of that goal must not become the controlling fact in 
efforts toward its realization. The categorical imperative insists only that the 
goal not be fundamentally contradicted and undermined. It fully recognizes 
that until the kingdom of ends is reached, there will be imperfections. See Hill 
(1991, 73), O'Neill (1989, 127-128), and Sullivan (258-260). 

11. Doyle (1983) and Dixon (1994) credit the Correlates of War Project with 
the establishment of the body of empirical research relating democracy and peace. 
See, [Dl instance, Smal1 and Singer (1976, 1982). An excellent review of the major 
themes in this body of research may be found in Chan (1997). 

23 



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