Simon Gros

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The lecture Kant on Perpetual Peace as Capacity proposes that Kant’s idea of perpetual peace must be grasped neither as a naturally given condition of human coexistence nor as a merely regulative horizon that forever eludes realization, but as a rational capacity whose very being consists in its exercise under historically and politically concrete conditions. Against readings that either naturalize peace as a state into which humanity could somehow “fall,” or spiritualize it into an ideal that never leaves the realm of pure reason, the lecture reconstructs perpetual peace as a practice-dependent power that arises through, and within, antagonism and unsocial sociability. It thereby reconfigures the relation between nature and freedom, conflict and concord, war and peace, such that peace becomes thinkable only where it is continually produced, revised, and endangered by finite rational agents whose failures of exercise are themselves moments in the unfolding of this capacity.

The lecture opens in a self-consciously modest way: Jovićević presents the argument as work in progress, raw and experimental in its articulation, yet anchored in a clear guiding intuition. This intuition is summarized in the claim that perpetual peace, as Kant uses the term, should be understood as the distinctive mode in which finite rational beings relate to one another as species beings and act in view of a non-conflictual coexistence within determinate social and political forms. Peace is not presented as an external configuration into which human beings might one day be inserted; it is described as an ongoing activity among human agents, as a perpetually renewed enterprise of institution and maintenance. Kant’s own formulation that peace is not a state but something that must be instituted and established by human beings is taken as a guiding thread, even if the exact wording of the citation is handled with interpretive freedom. The initial step is to dislodge, at the conceptual level, any temptation to treat peace as a given object, a state of affairs, or a once-for-all achieved equilibrium.

Yet, the lecture refuses to move directly from this negative clarification to a simple notion of peace as a “goal” or “ideal” to be approached. The conceptual difficulty appears precisely here: if perpetual peace is to be understood as a goal that ought to be achieved, its logical status as an ideal introduces a tension with its dependence on concrete instantiations in time and space. Kant himself, in the essay on universal history with a cosmopolitan intent, describes perpetual peace as a theoretical ideal that nevertheless has a practical function: it is what ought to be and what practical reason requires as a guiding principle. The lecturer isolates a crucial consequence: no finite set of actions or empirical examples could ever exhaust such an ideal, because the principle at stake is internally determined; nothing external can complete or close it. The ideal exceeds every instantiation without becoming external to the domain of practice; it is immanent to action while remaining irreducible to any particular action or state.

At this point, the lecture introduces the first major conceptual tension. If perpetual peace is an ideal whose logical principle is entirely internal, if it is a requirement of reason that cannot be exhausted by finite experience, how can it be reconciled with the claim that peace is an activity with natural, historical, and social conditions? Is the subject that exercises peace thereby torn away from nature, such that any exercise of peace would involve a discontinuity with natural forms and determinations? The dilemma is formulated in a stark way: either one abandons the conception of perpetual peace as a regulative normative ideal that finite beings strive to realize, or one abandons the idea of perpetual peace as a distinctive activity of natural, finite human beings. The lecture’s thesis is that this dilemma is spurious—a symptom of a dubious underlying conception of both perpetual peace and human nature.

The method is straightforward and dialectical. The first part reconstructs an image of peace as a static, harmonious natural state, an image that Kant explicitly rejects. The second part attempts to show how peace can be simultaneously a regulative ideal and an activity, by rethinking it through the concept of capacity, with the help of Aristotelian distinctions and Kantian themes of unsocial sociability and historical development. The “composition sequence” of the lecture is thus reflective: it first stages a conception only in order to dissolve it; then it rearticulates the problem at a higher level of complexity by reconfiguring the conceptual tools themselves.

The analysis of peace as natural state begins with an extreme idealization of nature: nature is imagined as an all-encompassing harmonious whole governed by laws in which every element occupies its appropriate place, as if in an idealized mechanical system. Within such a framework, any human action, however violent or morally reprehensible, remains fully inscribed in the causal order of nature and cannot perturb the fundamental harmony of this order. At the level of theological or metaphysical evaluation, such action would still count as “good,” because the only criterion of goodness would be conformity to the causal principle of nature itself. The lecture presses this paradox: in a truly unperturbed natural harmony, concepts such as good, evil, war, or peace lose their purchase, because there is no standpoint from which to judge deviations, and no conceptual space for genuine opposition.

This leads to an important conceptual step: in the imagined picture of a fully harmonious and self-contained nature, deviations would be merely privative differences—relative deficiencies that never reach the level of real negativity. A malfunctioning or a morally bad action would be an internal variation that does not disturb the unlimited and boundless whole. The lecture links this to a Hegelian motif: if nature is conceived as a locus of perfect bliss, a paradise in which human beings live in innocence, then this paradise is also, paradoxically, an “animal kingdom devoid of spirit.” In such a state, nothing like properly human existence becomes actual, because human existence, in its distinctive sense, presupposes the experience of opposition, internal division, and conflict. To know the good, one must have confronted the possibility of evil; to exercise freedom, one must have experienced the tension between natural inclination and rational legislation.

Through this detour, Jovićević arrives at a central insistence: human beings acquire their status as rational agents only by taking a distance from nature, by disrupting its supposed harmony. Violence, evil, and turbulence become conceptually significant not as accidental intrusions into an otherwise intact natural order, but as conditions of possibility for the very emergence of moral concepts, historical development, and sociality. If nature were indeed a perfectly harmonious whole, without internal blind spots or impurities, then any attempt to reflect upon it from an external point of view would be impossible. Everything would be encompassed by the same causal law, including any purported act of reflection itself.

The lecture draws a sharp consequence from this: if nature pervades everything as a totality, the principle of this totality cannot be verified anywhere in a determinate way. Nature’s harmony becomes conceptually unstable; the more comprehensive and all-encompassing it is supposed to be, the more it dissolves into indeterminacy. To even articulate the concept of such a nature requires a movement of distancing, an act of reason that places itself in a relation to nature rather than remaining indistinguishably within it. It is through this distancing that both nature as such and human nature become intelligible. Reason’s exercise is thus not a contingent supplement to an already-formed natural order; it is the condition under which nature can appear as a meaningful totality and under which human beings can understand themselves as beings of reason.

Here the lecture connects explicitly to Kant’s reflections in the essay on universal history. Kant describes the idea of a pre-social state of nature, a supposed original harmony in which human instincts function without the discipline of political institutions, as an untenable fantasy. The thought that one could simply withdraw from culture and state into a pure natural condition is criticized as a projection that fails to recognize its own dependence on rational reflection. The same holds for idealized conceptions of the state as a perfectly harmonious institution: such ideas are always already products of rational capacities that reflect, systematize, and criticize what is given. Jovićević emphasizes that both myths—the myth of a fully good nature and the myth of a fully harmonious state—presuppose, as their condition of possibility, the work of reason that distinguishes itself from any simple givenness.

This has a direct bearing on the concept of peace. If nature is internally riven by antagonism and unsocial sociability, if human beings are compelled by their very nature to seek power, to arrange the world according to their own will, and to enter into conflicts, then peace cannot be understood as an effortless state that emerges from natural harmony. Peace, in Kant’s sense, requires legal and political forms that constrain and shape the exercise of freedom; it requires institutions that transform unsocial sociability into a productive tension that drives culture, history, and moral development. The lecture’s point is that such institutions, and the activities that sustain them, are themselves expressions of rational capacity, grounded in the very structure of human nature as a nature that includes reason.

The concept of unsocial sociability is brought in here as a pivotal Kantian idea: human beings possess a tendency to enter into society and, at the same time, to withdraw from it through self-interest, competition, and desire for distinction. This tension generates conflict, yet it also forces individuals to develop their abilities, to refine their capacities, and to participate in collective arrangements. The lecture emphasizes that this antagonism is not an external intrusion into a pre-existing peaceful order; it is internal to the concept of human nature and to the concept of nature itself, once the latter is understood as including the possibility of rational reflection and freedom. Without conflict and division, there would be no history, no culture, no education, and indeed no nature in the fully conceptual sense: nature would remain a mere backdrop, devoid of the dynamic by which its own principle becomes manifest.

At this juncture, the first part of the lecture closes with a decisive reversal: nature, to be conceptually intelligible, must be thought as inherently including the possibility of human freedom and rational action. This implies that nature is “shot through” with blind spots and impurities; it is not a completed harmony, but a field of tensions in which the exercise of reason introduces instability, unpredictability, and conflict. This does not mean that nature is chaos; rather, the principle of nature must be understood as including within itself the capacity for its own conceptualization, which occurs through beings capable of taking distance from it. The myth of a simple paradise is thereby dissolved, and with it, the idea that peace could ever be a pre-given natural state.

The second part of the lecture reopens the problem at a higher level of complexity: if conflict and struggle are necessary for the unfolding of human and natural capacities, how can one still speak of perpetual peace as a normative goal? How can peace be at once an ideal and an activity that occurs precisely within, and through, antagonism? Jovićević explicitly warns against a too rapid embrace of phrases such as “dynamic process” or “second nature,” which would merely shift the myth of harmony from a static to a movement-based model, without doing justice to the unresolved contradictions at stake. There is a risk that conflict and violence become absorbed into an encompassing narrative of development, such that they lose their normative negativity and are treated as inevitable stages in a teleological process.

To avoid this flattening, the lecture proposes a conceptual reconfiguration: perpetual peace should be understood as a capacity—a rational power whose very being consists in its exercise. Here Aristotle’s analysis of capacities plays a crucial role. In Metaphysics Θ and related passages, Aristotle distinguishes between capacities that are possessed by nature and manifest independently of exercise, and capacities that are acquired only through being exercised. The voice does not arise through speaking, nor do eyes arise through seeing; these are natural capacities that precede their acts. By contrast, skills such as playing the lyre, making coffee, or doing philosophy exist only by being practiced. Their acquisition is intrinsically tied to their exercise; one learns by doing.

The lecture stresses that Aristotle’s distinction is logical, not chronological. It does not simply separate what we have at birth from what we acquire later. Rather, it distinguishes two ways in which the relation between capacity and act can be conceptualized. In natural capacities, the capacity explains the act independently of any prior exercise. In rational capacities, the capacity becomes what it is only in and through its acts. Thus, rational capacities are two-way and practice dependent: they can be used for opposed aims (medicine can heal and harm), and they are constituted by the very process of being exercised in determinate practices and institutions.

Kant’s notion of reason as a Vermögen that requires trial, exercise, and instruction is brought into alignment with this Aristotelian model. The lecture recalls Kant’s formulation that reason is a faculty that does not operate instinctively but requires learning by doing. Rational beings are not furnished by nature with fully formed rational capacities; they acquire these capacities by exercising them in practice. The lecturer explicitly ties this to the concept of perpetual peace: if peace is a rational capacity, then it cannot be understood as something that we simply possess as a given property. It exists only in the measure that it is exercised in concrete social and political arrangements.

This leads to a significant re-interpretation of Kant’s claim that perpetual peace is an ideal needed for practical purposes. The ideal is no longer an external yardstick against which we measure actions; it becomes the internal normative structure of a capacity that is realized only through practice. Peace as capacity is a unity of foundation and exercise: its normativity is anchored in reason’s demand for universality and non-contradiction, but its concrete content arises only through historical attempts at institution, through successes and failures in legal and political construction, and through critical reflection on these attempts.

The lecture does not gloss over the problem that rational capacities are two-way. Precisely because reason is capable of determining itself in different directions, the capacity for peace can misrepresent itself and be used to justify war and domination. As medicine can heal or poison, so the discourse of peace can be mobilized to legitimate imperial aggression or structural violence. This is where the original worry from the abstract re-enters the argument: if war and conflict are in some sense fundamental to the actualization of peace, does Kant thereby become a propagator of war?

Jovićević’s answer hinges on the notion of failure of exercise. The fact that a capacity can be misused does not invalidate the capacity as such; rather, failures of exercise reveal the normative structure of the capacity by making visible where practice has deviated from its rational ground. The two-way character of the capacity is not symmetrical: although the same conceptual resources might be mobilized in the service of war under the heading of “peace,” reason retains the ability to uncover contradictions, to expose misrepresentation, and to revise practices. The rational capacity to strive for peace includes within itself the demand to distinguish genuine from false peace, to diagnose “fake peace” as a fragile construction that covers over unresolved antagonisms.

In this sense, the lecture suggests that Kant’s teleological reflections on nature’s “trick”—for example, nature’s tendency to push human beings toward commerce, competition, and indirect cooperation—can be read without attributing to Kant a naïve optimism about war as a straightforward instrument of progress. The “trick of nature” is not a guarantee that every conflict serves the realization of peace. Rather, it marks the structural fact that human antagonisms, once mediated by legal and economic institutions, can be transformed into engines of development, provided that reason critically guides this process. The danger is real: the same structural forces can produce devastation, regression, and new forms of barbarism. The capacity framework makes this ambivalence explicit.

The lecture’s outer framing becomes especially visible in the closing gestures, where Aristotle’s lesson that we learn by doing is brought together with Kant’s insistence that rational beings can expect their errors to become visible over time. There is no certainty that perpetual peace will ever be fully realized; there is, however, a rational ground to expect that systematic contradictions in our forms of coexistence will not remain hidden indefinitely. The continual striving to actualize peace, to correct our institutions, and to learn from past failures is presented as intrinsic to the exercise of the capacity itself. Peace is not the absence of conflict but the ongoing transformation of conflict by rationally guided practices that seek to render social life compatible with freedom and dignity.

The subsequent discussion, in the question period, does not simply append external concerns; it deepens and complicates the lecture’s central claims. A first question addresses the relation between peace as capacity and the concept of evil. In Kant’s moral philosophy, evil is often understood as a privation of the good, a failure to determine oneself by the moral law. How then could the same rational faculty that aims at peace also bring about evil? The lecturer responds by pointing to Kant’s complex conception of radical evil, which involves not a simple absence of good but a perverse reversal of priorities in the maxim: the good is affirmed only on a negative basis. Within the context of perpetual peace, Jovićević’s emphasis lies on showing that the conceptual space for moral categories arises only once conflict and opposition are in play. The very idea that evil could be a ground for the actualization of good indicates that evil cannot be reduced to sheer privation.

A second intervention shifts the focus to the terminology: capacity, faculty, Vermögen. The worry is that appealing to Aristotelian notions may obscure the specificity of Kant’s theory of faculties, in which the Vermögen of reason, understanding, and will have distinct roles. The questioner asks whether the lecture’s usage of “capacity” risks conflating these distinctions, and whether what is at stake might be better described as an exercise of causality rather than of capacity in a strict sense. Jovićević replies by indicating that what matters is not a terminological alignment but a structural insight: the faculty at issue in perpetual peace is rational in a way that precludes its isolation from actualization. The concept of Vermögen operative here corresponds to the Aristotelian type of capacity that exists only in exercise: a rational power whose normativity cannot be grasped independently of its instantiation in social and political forms.

A third intervention, more expansive, draws a parallel between perpetual peace and other postulates of practical reason, particularly the postulate of immortality. In Kant’s ethics, the finite temporal order of human life is insufficient for a complete realization of moral goodness; the postulate of an endless progress toward holiness compensates for this finitude. Analogously, the commentator suggests, perpetual peace functions as a temporal extension that allows the species to continue striving toward a regulative idea despite persistent failure. The lecture’s insistence on peace as capacity is thereby re-situated: the capacity unfolds across generations, in the history of humanity as Gattung, and its exercise presupposes an open-ended temporal horizon. Furthermore, the notion of an innate propensity to evil, understood by Kant as self-produced and rooted in an intelligible act, is reinterpreted at the species level: the collective history of humanity reproduces in another key the structure of the individual’s moral development.

The final question returns to Aristotle’s two-way capacities, using examples such as building and destroying, healing and poisoning. The interlocutor suggests that the knowledge required to build already entails the knowledge of how to dismantle; to know how to heal is, in a sense, to know how to harm. On this model, the capacity for peace would intrinsically include the capacity for war, in a manner that is not simply a matter of misapplication. The lecturer’s response again emphasizes the asymmetry: the fact that genuine expertise implies an understanding of how things can go wrong does not mean that failure is on an equal footing with success. What is crucial is that failed exercises of a capacity expose its normative structure. The falling building or the poisoned patient reveal, in a dramatic way, what the proper exercise should have secured. Transposed to the domain of peace, misuses and “fake peaces” expose hidden contradictions in institutions and practices; they are moments through which the rational content of the capacity becomes more sharply articulated.

If one steps back from the detailed argumentative movements, the distinctive contribution of the lecture can be formulated as follows. It offers a conceptualization of Kantian perpetual peace that refuses to anchor it either in a metaphysical picture of nature as harmonious totality or in a purely formal ideal detached from practice. By embedding peace within the structure of rational capacity, the lecture shows how peace is dependent on conflict without rendering war inherently desirable; how it is conditioned by nature without being reducible to natural development; and how it is normative without achieving a definitive, completed state. The capacity model makes it possible to grasp perpetual peace as a unity of ideality and actuality, of ought and is, in the dynamic of learning by doing that characterizes finite rational agents.

The constructive convolutions of the argument—all the detours through nature’s harmony, Hegel’s zoological garden, unsocial sociability, Aristotelian capacities, radical evil, and postulates of immortality—serve a coherent aim: to make explicit the inner tensions that inhabit the concept of peace, and to show that these tensions are not defects to be eliminated but structures to be acknowledged and worked through. The lecture thereby displaces the simplistic question of whether Kant “propagates war” by a more refined inquiry into how peace can be genuinely thought under conditions of conflict. War and evil appear as both threats and conditions: they are the negative moments through which the capacity for peace becomes actual, which does not mean that they are in themselves rationally endorsed.

The lecture invites a specific kind of hope, one that is neither eschatological nor complacent. The hope is grounded in the rational expectation that failures of peace—wars, injustices, falsified reconciliations—are not opaque accidents but intelligible misapplications of a capacity that remains in force even when misused. To exercise the capacity for perpetual peace is to conduct political and social life under the assumption that contradictions can be brought to light, that institutions can be revised, and that learning from history is possible. Perpetual peace, on this reading, is less a distant endpoint than a mode of rational perseverance: the ceaseless work of finite beings who, precisely because their nature is fractured, remain capable of transforming conflict into a more just and peaceful coexistence.