Simon Gros

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The lecture advances a precise and demanding thesis: that Kant’s sparse formulation of cosmopolitan right in the third definitive article of Toward Perpetual Peace contains, once read through the lens of his practical philosophy, a normatively complex and structurally ambivalent right not to be treated with hostility. Corinna Mieth’s contribution lies in reconstructing this right through a conceptually fine-grained account of hostility in Kant’s ethical and juridical writings, developing a taxonomy of wronging that exceeds the usual focus on instrumentalization, and then using this framework to interrogate contemporary European migration politics. The lecture’s distinctive achievement is to show how the apparently thin legal right of a peaceful foreigner to present himself and to be spared hostile treatment rests on deep tensions within Kant’s system between personhood, war, commerce, self-love, and the attitudes of fear and contempt that animate xenophobic politics.

The lecture is framed from the outset by a double movement. On the one side stands the familiar, often celebrated, passage from the third definitive article: cosmopolitan right as the right of a stranger not to be treated in a hostile manner upon arrival on another’s territory, provided he behaves peacefully; the claim to present oneself to society grounded in the common possession of the earth’s surface; the insistence that originally no one has more right to be at any place on earth than anyone else. On the other side stands the observation that this passage has generated mainly three types of interpretation, each of which tends to pull the text in a specific direction and thereby risks occluding the particular problem Mieth wishes to bring into focus. Ethical readings treat universal hospitality as a virtue of cosmopolitan citizenship, a matter of character and beneficent openness. Historical readings reconstruct concrete practices, such as duties of innkeepers towards foreigners or Kant’s anti-colonial critique of European treatment of Indigenous peoples, as contexts in which this right acquires determinate content. Legal-political readings attempt to derive contemporary rights—rights to asylum, residence, access to citizenship—from Kant’s formula. Mieth accepts the legitimacy of these approaches yet proposes to suspend their expansive ambition and ask a narrower and in some ways more demanding question: what does it mean, ethically and juridically, to treat someone with hostility in the precise sense required for this right to be intelligible?

From this initial framing the lecture proceeds with an almost architectonic clarity. The composition sequence is explicitly laid out: first, an analysis of hostility as such, with three dimensions distinguished and then conceptually reorganized; second, a reconstruction of hostility as a form of wrongdoing that extends beyond the usual Kantian theme of using others as mere means; third, an exploration of institutionalised hostility in migration politics, focused on three exemplary cases and evaluated with the aid of the earlier conceptual distinctions. The outer framing of the lecture—as the final paper of a day concerned with war, peace, and cosmopolitan right—exerts a constant pressure on this structure: the question of war re-enters through the technical juridical sense of hostilities, while the question of peace reappears through Kant’s reflections on commerce and the teleology of history. This compositional structure allows the lecture’s earlier, seemingly abstract distinctions to be gradually displaced by more concrete normative conflicts, without ever being abandoned.

Mieth’s point of departure is disarmingly modest: a definition of hostility from the Oxford dictionary. Yet this modesty is methodical. She uses the dictionary’s distinctions to differentiate three basic senses of hostility and then gradually reworks them in Kantian terms. First, hostility as feelings and attitudes toward persons—animosity, hatred, xenophobia, fear of those perceived as foreign or alien. Here she recalls terms like Fremdenfeindlichkeit and xenophobia, stressing that in this sense hostility names a practical orientation toward persons from other backgrounds, experienced as threat and expressed in exclusionary sentiments. Second, hostility as strong and angry opposition to ideas, plans, or situations: opposition to nuclear power, for instance, directed at a policy rather than a person. This form can in principle be justified or unjustified depending on the quality of reasons, their proportionality, and their relation to public argument. Third, hostility as a technical juridical term denoting acts of fighting in war—the outbreak or cessation of hostilities, the conduct of armed conflict.

This triad already anticipates the later Kantian distinctions. Hostility as affective attitude toward persons (A), as opposition to ideas (B), and as warfare (C) each raises different normative questions. The second can belong entirely within the space of rational disagreement; the third, in Kant’s theory, can be justified under conditions of self-defence in the state of nature between states; the first seems, at least in Kant’s ethical writings, to be disqualified as a vice. The initial problem therefore emerges in the form of a tension: ethical hostility is condemned, juridical hostility is sometimes authorized, and yet Kant deploys the same word across these contexts. Mieth formulates this as the question: what kind of wrong is hostility in Kant’s system, and when, if at all, can treating someone with hostility be adequate?

To answer this, she turns away from Perpetual Peace to Religion within the Boundaries of Mere Reason, where Kant offers a psychological-ethical genealogy of vice. There, hostility appears as a culmination of comparing self-love. Self-love, when combined with constant comparison to others, yields first a wish for equality—no one should rise above oneself—and then, through anxiety about others’ possible advantage, a craving for superiority. Jealousy and rivalry emerge, and from these arises a disposition toward secret and open hostility toward those perceived as alien. Kant describes this as the stance of an enemy of humanity, who finds satisfaction when others fare badly. Hostility in this sense is intrinsically vicious: it is anchored in a pleasure in others’ misfortune, independent of any legitimate claim of self-defence.

On the other hand, in Toward Perpetual Peace Kant explicitly authorizes states to resort to war under the conditions of the natural condition among states. In this context, hostilities are a permitted way for a state to pursue what it takes to be its right, when injured and absent a higher coercive power. The theory of just war Kant sketches here reduces legitimate war to self-defence against aggression. The right to engage in hostilities in this technical sense is thereby preserved as a juridical possibility. Mieth underlines how this dual usage generates an apparent clash: hostility as ethical vice and hostility as juridical instrument of self-defence coexist in the same system.

Rather than treating this clash as a simple contradiction, Mieth re-poses the question in a more refined way. The core difficulty is not merely that hostility is sometimes condemned and sometimes allowed, but that it appears to undermine the very formula that guides Kant’s ethical theory: the Formula of Humanity. If one must always treat humanity—whether in one’s own person or in that of another—always at the same time as an end in itself, then how can killing enemies in war ever be compatible with this requirement? More generally, how can inflicting harm, coercively restraining, or deporting someone be reconciled with respect for their dignity? The lecture’s central conceptual work is devoted to developing an answer that preserves the normative force of the Formula of Humanity while allowing for the juridical reality of conflict.

Mieth’s innovation consists in expanding the usual interpretation of the Formula of Humanity. In many discussions, the contrast is cast in simple form: treating someone as an end in themselves versus treating them merely as a means. The prohibition of instrumentalization then becomes the central content of the formula. Mieth insists that this reading is incomplete. There are forms of grave wrongdoing in which persons are not used as instruments at all, yet their status as persons is still violated. The operative distinction is therefore not exhausted by “end versus mere means.” It requires a more complex array of practical attitudes.

She begins from Kant’s distinction between persons and things. Persons have absolute worth: their value does not arise from their usefulness or their place in someone’s projects. Things, by contrast, have only relative worth: they are valuable insofar as they serve the ends of agents. To treat someone as a person means to regard them as the supreme limiting condition of one’s ends; as soon as another person’s equal status enters the field, one’s own ends can only be pursued under the constraint of their dignity. Treating someone as a thing, conversely, means ascribing value only relative to one’s purposes: useful, irrelevant, useless, or obstructive.

From this starting point Mieth distinguishes several species of wrongdoing associated with regarding others as things. Instrumentalization—treating someone as a mere means—is only one of them. A person can also be treated as irrelevant, as if their fate did not matter. She invokes the familiar example of walking past a drowning child in a shallow pond. In such a case, the child is not being used to advance any end; the wrong consists in acting as if the child’s life had no standing at all, as if it were morally negligible. This is incompatible with treating the child as a person, yet it is structurally different from using them as a tool. A third form arises when others are treated as mere obstacles: bodies or presences that stand in the way of one’s projects and must be removed. Here the relation is again distinct from instrumentalization. A means is something one seeks to employ; an obstacle is something one seeks to get rid of.

Mieth finds it striking that Kant does not explicitly theorize this category of “mere obstacle,” even though much historical injustice—especially colonial displacement of existing populations—fits this pattern. Settlers did not always need Indigenous people as instruments; often their mere existence in the territory marked them as impediments to be cleared away. Classifying such treatment solely under “using others as mere means” misses an important modality of disrespect.

Yet even the expanded distinction between treating others as ends and treating them as things still fails to capture all morally salient forms of hostility. For people can also be wronged as persons, when they are taken up as negative ends: objects whose harm, humiliation, or destruction is the very goal of action. In this mode the other is not denied personhood; instead, their personal status becomes the focus of malice. Mieth references Schopenhauer’s tripartite scheme—egoism, altruism, malice—to illustrate this point. Malice, in Schopenhauer’s description, involves harming others for its own sake, even at cost to oneself. This does not reduce to self-interest; it is a form of evil. Mieth, drawing on her own work with Jakob Rosenthal, calls this treating others as negative ends, and suggests that such cases fit Kant’s category of radical evil better than they do simple instrumentalization.

The resulting taxonomy of practical attitudes is threefold. One can treat or regard others as ends in themselves, respecting their dignity and allowing their claims to limit one’s projects. One can treat them as things, ascribing only relative value and classifying them as useful, irrelevant, useless, or obstacles. Or one can treat them as negative ends, taking their suffering or destruction as part of one’s purpose. Hostility, in the ethical sense—hostile attitudes towards persons one sees as alien—tends to occupy this third category: others become negative ends, to be excluded, humiliated, or harmed as such.

With this taxonomy in place Mieth returns to the earlier threefold dictionary distinction and performs a conceptual alignment. Hostility as an attitude towards persons (type A) is wrongful whenever it conflicts with treating them as ends in themselves; it tends to coincide with treating them as negative ends. Hostility as opposition to ideas (type B) can be legitimate when it remains oriented to reasons and directed at proposals rather than persons. Hostilities as acts of war (type C) can be legitimate in Kant’s system when they remain within the limits of a just war of self-defence and respect the constraints on treatment of enemies.

This last point leads Mieth to perhaps the most subtle distinction of the lecture: the difference between treating someone as an enemy and treating them as a mere enemy. She builds here on an analogy introduced by Martin Sticker in recent work: just as one can treat someone as a means without reducing them to a mere means, so one can treat someone as an enemy without reducing them to a mere enemy. To treat someone as a mere enemy would be to strip them of equal moral status and basic rights, to remove them from the common legal and moral universe. Enemy combatant designations and forms of Feindstrafrecht—criminal law that creates a lesser category of person considered outside ordinary rights—are contemporary examples of such reduction. By contrast, to treat someone as an enemy in Kant’s juridical sense is simply to regard them as a member of a hostile army in a situation of war, subject to the rules of war and human rights protections. The Geneva Conventions become here a practical articulation of what respecting an enemy as a person entails.

In this way Mieth suggests that hostility in the juridical sense can be compatible with the Formula of Humanity. One may fight, even kill, combatants in a just war while still regarding them as persons—provided one does not strip them of their status, subject them to arbitrary cruelty, or annihilate the legal constraints on warfare. The right not to be treated with hostility in the cosmopolitan context thereby becomes more precise. It is not an unconditional prohibition of any oppositional or coercive treatment. Rather, it prohibits treating peaceful strangers as mere enemies, as negative ends, obstacles, or threats whose very presence legitimizes their exclusion. Foreigners who behave peacefully may still be turned away under certain conditions, provided this does not entail their destruction. Yet as long as they behave peacefully, hosts may not treat them with hostility in sense A, nor may they subject them to treatment that presupposes their lesser status.

At this point the structure of the lecture begins to shift. The conceptual architecture of hostility—person, thing, negative end; enemy, mere enemy—is in place, and Mieth turns to the institutional sphere. She asks when representatives of democratic states treat migrants with hostility in sense A, and whether hostility toward migrants can ever be justified in senses B or C. This transition displaces the previous focus on pure theory without abandoning it; the theoretical distinctions now function as lenses through which to view contemporary political rhetoric and policy.

To elucidate this, Mieth recalls the role commerce plays in Kant’s vision of Perpetual Peace. In the third definitive article Kant explicitly ties cosmopolitan right to the conditions making peaceful commerce possible. The authorization for a foreign newcomer does not extend beyond what is required to seek commercial interaction. In this way, distant regions can enter into peaceful relations that may gradually become governed by public law and thereby advance humanity toward a cosmopolitan constitution. If one accepts the reading of Perpetual Peace as peace through law, then commerce becomes a central driver of this teleology. Mieth emphasizes that, for Kant, those who come peacefully and have something to offer—for him primarily goods, for contemporary migrants often their labour power—ought to have the possibility to engage in commerce and, she suggests, some prospect of moving from passive to active citizenship. The mere avoidance of violating negative rights may therefore be insufficient; a genuine cosmopolitan order would require structures enabling peaceful newcomers to become full members of society.

This is where Kant’s doctrine of virtue becomes salient again. In the Doctrine of Virtue Kant distinguishes the friend of humanity, the enemy of humanity, and the selfish person. The friend of humanity is disposed to find satisfaction in the well-being of others, to exercise beneficence, to respond with sympathy and benevolence. The enemy of humanity, by contrast, rejoices in others’ misfortune; his attitude is malevolence, Schadenfreude, a wish to see others suffer. The selfish person is neither moved by others’ happiness nor misery; he is indifferent to others as long as things go well for himself. In the context of migration politics, Mieth suggests, Kantian cosmopolitanism may not demand that citizens and politicians act as friends of humanity in the full ethical sense, greeting everyone with universal hospitality. It may suffice, for a minimal yet stable peace, that they behave as self-interested agents constrained by respect. That is, they trade with newcomers, welcome their contributions to commerce, and refrain from hostility, even if they do not cultivate a comprehensive ethic of friendship. Commerce then appears as a middle position between vicious hostility and virtuous cosmopolitan friendship: self-interest, within the limits of respect, can support a peaceful order.

Yet this middle position itself rests on a psychological structure that is internally fragile. Returning again to the passage from Religion, Mieth highlights Kant’s analysis of comparing self-love. Human beings tend to evaluate their own happiness by comparison with others. This generates two main orientations. There is a hostility of fear, arising from upward comparisons. Others who appear to be advancing are construed as threats; one fears being overshadowed or displaced. This form of hostility gives rise to malice, ingratitude, revenge. And there is a hostility of contempt, arising from downward comparisons. Others are seen as of lesser worth, beings who should remain in their place; arrogance and disdain become the characteristic vices.

These two forms map closely onto contemporary xenophobic rhetoric. Hostility of fear manifests as narratives of invasion, of foreigners “taking over,” of economic and cultural displacement. Hostility of contempt appears in patronizing discourses in which those with migrant backgrounds are told that gruelling, low-paid work is the best dignity they can hope for, while their actual socioeconomic conditions remain obscured. Mieth’s classification here allows her to differentiate more precisely between different types of hostile attitudes that may be present in political speech.

With this conceptual apparatus fully in place, Mieth introduces three political examples. The composition of the lecture now shifts into a more case-based argumentative mode, where the earlier distinctions are put to work.

First, Theresa May’s famous aim as Home Secretary to create a “really hostile environment” for illegal migration in Britain. In this case hostility is explicitly named and codified as an institutional goal. Mieth interprets this as hostility of type A: hostility toward persons, directed at irregular migrants as such rather than at any specific crime or policy. Where migrants behave peacefully and offer their workforce, constructing a general atmosphere of hostility toward them exemplifies hostility of fear and xenophobia in Kant’s sense. It aligns with the vice Kant ascribes to the enemy of humanity: a stance that wants others to fare worse, even where this brings no particular benefit to oneself. In such cases, Mieth intimates, the attitude is not even straightforwardly egoistic. It is determined by a wish that others fail, a wish that may persist against self-interest, since the labour and skills of migrants could be economically beneficial.

Second, Emmanuel Macron’s statement addressed to people with migration backgrounds in the Paris suburbs, to the effect that the state has nothing better to offer them than jobs requiring sixty to seventy hours of work per week to secure a minimum wage, and that this is better than “hanging around and selling drugs” because it provides dignity, for instance as Uber drivers. Here hostility is more implicit and ambivalent. At first glance the speech appears to encourage work and to connect it with dignity. Yet Mieth notes that, in light of empirical sociological knowledge, many those addressed already held two jobs yet still could not make a living, and that resorting to precarious platform work was a third, exploitative option. To frame this as the pinnacle of dignity available, while accusing those who remain unemployed of turning to crime, reveals a pattern of hostility of contempt. Others are positioned as lesser, as needing to accept exhausting and poorly paid labour as a favour granted to them. The vice at work corresponds to Kant’s description of arrogance in the Doctrine of Virtue: a person who seeks followers whom he feels entitled to treat with contempt, and who thereby violates the respect owed to human beings as such.

Third, Lithuanian foreign minister Gabrielius Landsbergis’s statement that Lithuania will not grant asylum to Russians who flee mobilization, because Russians should stay and fight against Putin. Here the normative configuration is more complex. Some journalists have interpreted this as unjustified hostility, since returning such refugees would mean sending them into a situation where they risk destruction—front-line deployment in Ukraine under conditions known to be deadly. This would violate Kant’s condition that turning a foreigner away is permissible only when it can be done without causing his destruction. Others have argued that some of those fleeing may be spies or regime supporters, which might, in principle, justify treating them as enemy agents. Yet as Mieth notes, such arguments function at the level of group suspicion; they treat individuals as members of a collective enemy rather than as persons who must be judged case by case. This runs counter to Kant’s insistence on equal law. Finally, the remark that Russians should stay and fight for justice in their own country raises the question of whether individuals have an obligation to remain under despotic rule in order to resist, and whether third parties may compel them to fulfil such an obligation by withholding asylum. Here we encounter an internal limit of Kant’s system: he denies a right to rebellion, yet projects a historical teleology in which states eventually become republican. The mechanism by which this should occur, and the relation between that teleology and cosmopolitan right, remains obscure.

The discussion period that follows the lecture foregrounds these tensions and, in doing so, displaces some of the initial balances Mieth had achieved. One interlocutor questions whether there truly is any deep contradiction between the ethical and political senses of hostility in Kant. The right to self-defence at the ethical level already presupposes that hostility against an unjust attacker can be justified; in this sense the ethical and juridical doctrines are parallel rather than divergent. On this view, the description of hostility as vice in Religion concerns cases where no legitimate self-defence is in play. Mieth acknowledges the force of this clarification yet maintains that the ethical concept of hostility as a pervasive attitude—finding oneself well only when others fare badly—goes beyond discrete acts of self-defence and can suffuse legal and political institutions, especially when entire groups (such as migrants) are framed as threats.

The same interlocutor also presses the third case: if one denies asylum to Russian draft evaders on the ground that they ought to fight for justice at home, then one risks undermining the right of asylum more generally, since a similar demand could be made of all refugees from unjust regimes. Mieth agrees that, in practice, the right of asylum in contemporary law is foundational, and that group suspicions about spies cannot function as independent reasons for refusal, since any state’s citizens could in principle include spies. Her hesitation pertains rather to what can be derived from Kant’s own texts. Kant’s passage in Perpetual Peace suggests that turning away someone who will be destroyed upon return is prohibited. This supports at least a minimal right of refuge. Whether it extends to the broader, contemporary understanding of asylum remains, for her, an open question within Kant’s framework, even if moral judgment today would condemn the kind of blanket refusal Landsbergis proposes.

Another participant brings Rousseau and Marx into the conversation, thereby complicating the earlier categories of means, obstacles, and negative ends. Rousseau’s analysis of amour-propre in both discourses, and especially his remark that some states value citizens only in terms of their contribution to the economy, suggests a structural tendency to treat human beings as disposable surplus—sometimes with a value lower than zero. Marx’s account of the English treatment of Irish workers introduces a dynamic in which capitalists stoke hostility among workers to weaken solidarity and depress wages. This raises the question whether treating humans as “obstacles” might be interpretable as treating them as negative instruments: there is demand for certain types of labour, but when there is oversupply, those same labourers are experienced as obstacles to accumulation, and their exclusion becomes a goal.

Mieth responds by reinforcing the distinction between competition and enmity. Legitimate economic competition can exist and even drive prosperity; however, when competitors are discursively turned into enemies—through images of invasion, or through depictions of migrants as a dangerous mass—then the category of “mere enemy” is approached. At that point, empirical reality (no military invasion, only individuals seeking work) diverges sharply from the hostile framing, and the attitude of hostility reveals itself as irrational in Kant’s sense: it undermines even the agent’s own self-interest, since the potential benefits of commerce are sacrificed to xenophobic satisfaction. She also notes the additional instrumentalization that occurs when politicians deploy such framings strategically to gain votes. In that case, migrants are treated simultaneously as obstacles (to be kept out) and as means (for mobilizing electoral support), while their status as ends in themselves is entirely suppressed.

A further question presses on the legal character of cosmopolitan right itself. Kant is clear that cosmopolitan right is a right, not an expression of philanthropy. The duty not to treat foreigners with hostility is a juridical duty, a perfect duty of states. Its force rests in the fact that its violation would justify coercion. One participant suggests that this implies a right of enforcement from below: when states enact laws that flatly forbid immigration and thereby deny the possibility even of presenting oneself, those seeking entry may themselves enforce their cosmopolitan right by entering irregularly. In this interpretive line, migrants who cross borders despite restrictive laws are vindicating their right to appear and offer themselves to society.

Mieth finds this idea intriguing yet sees limits in Kant’s text. The right Kant articulates, she notes, is the right to present oneself, to “offer oneself” to society, grounded in the shared possession of the earth. This implies that newcomers must have at least the physical possibility of arrival and self-presentation. However, if those to whom the offer is made decline—if they do not wish to trade goods, to hire labour, to enter any economic relation—the right does not obviously extend further. At that point the situation shifts from questions of justice to questions of beneficence. Kant can demand that we be beneficent toward those in need, but this demand has a different structure than the right of hospitality. Mieth nonetheless insists that the first stance toward migrants ought to be one of respect, not of charity: they should be seen as potential partners in commerce and citizens in the making, not as burdens whose presence activates only duties of aid.

These exchanges in the discussion period subtly alter the balance of the lecture. In the main body, the trajectory had led from Kant’s texts through conceptual analysis to critical application and then to a cautiously hopeful role for commerce and self-interest as drivers of peace. In the discussion, the unresolved difficulties of Kant’s teleology, his silence on rebellion, and the structural injustices of contemporary capitalism re-enter the scene. The earlier middle position—selfishness constrained by respect—comes under pressure from Marxian and Rousseauian analyses of structural hostility: when the economic order itself treats some lives as surplus, self-interest and hostility can coincide, rather than being opposed. Commerce in such a setting may amplify hostility rather than channel it into peace. Without external theoretical resources, however, Mieth remains within Kant and limits herself to showing how, from a Kantian standpoint, hostility of fear and contempt is irrational even on its own self-interested terms.

In this sense, the lecture’s argumentative narrative can be seen as a series of partial displacements. It begins with the legal formula of the third definitive article, then is displaced by the ethical analysis of hostility in Religion and the Doctrine of Virtue; this ethical analysis is displaced in turn by a more comprehensive taxonomy of practical attitudes that includes negative ends; that taxonomy is then displaced by the juridical distinction between enemy and mere enemy, which reframes the permissibility of war; and finally this entire conceptual edifice is displaced by the realities of migration policy and political rhetoric, where commerce, fear, contempt, and security concerns intertwine. Each new layer does not abolish the previous one. Rather, it re-situates it: the right not to be treated with hostility no longer appears as a thin, almost marginal clause, but as the surface point of contact between deeply rooted ethical attitudes and hard political decisions.

What emerges, through this layered reconstruction, is an image of Kant’s cosmopolitanism as structurally ambivalent. On the one hand, Kant’s grounding of cosmopolitan right in the common possession of the earth and his insistence that no one has an original right to any particular place provide powerful resources against nationalist closure and colonial adventure. The right of a peaceful stranger to present himself and to be spared hostility is a normative minimum that can be deployed in critiques of state practices that construct entire groups as dangerous and expendable. On the other hand, the restriction of cosmopolitan right to a right of visit, the emphasis on commerce, and the absence of a right to rebellion all limit the extent to which Kant’s texts can straightforwardly vindicate robust contemporary rights to asylum and migration. Mieth’s lecture refuses both an easy celebration and a simple dismissal. It insists instead on the difficulty of the terrain: cosmopolitan right is neither empty nor sufficient.

The lecture’s distinctive contribution, then, can be articulated in several dimensions. Conceptually, it enriches Kantian ethics by showing that the Formula of Humanity, if restricted to the prohibition of using others as mere means, fails to capture central forms of hostility: treating others as obstacles, as irrelevant, or as negative ends. This ampliative reading allows Kantian ethics to accommodate phenomena of hatred, humiliation, and structural exclusion that are central to migration politics. Juridically, it clarifies how Kant’s authorization of war can be reconciled with respect for persons by distinguishing enemy from mere enemy and by insisting on legal constraints on the treatment of opponents. Politically, it demonstrates that contemporary practices of creating “hostile environments” for migrants involve precisely those forms of hostility Kant diagnoses as vices: fear of what is alien and contempt for those positioned as lesser. Teleologically, it explores the role of commerce as a driver of peace, while registering its dependence on attitudes that remain fragile and prone to degeneration into xenophobia.

Perhaps the most important clarification concerns the status of the right not to be treated with hostility itself. In Mieth’s presentation, this right emerges as a threshold concept. Below it lies the realm of hostility of fear and contempt, where foreigners are framed as invaders, as threats, as burdens; above it lies the more demanding realm of cosmopolitan friendship, where moral agents cultivate active benevolence and solidarity. The threshold does not guarantee inclusion, citizenship, or equal participation. It guarantees only that peaceful presence cannot be met with hostile exclusion or destructive refusal. Yet precisely because this right is minimal, its violation is revealing. When policies or discourses aim to produce hostility toward categories of migrants, they disclose an ethical failure that is intelligible within Kant’s own framework, without recourse to external theories. In that sense, Kant’s cosmopolitanism, limited though it is, still furnishes standards by which to judge even those who claim to act in the name of security or national interest.

The lecture closes with a candid acknowledgement of remaining uncertainties. Hostility is morally wrong whenever it conflicts with treating others as ends in themselves; legal hostility may be justifiable from a Kantian standpoint when it remains within the bounds of self-defence and respect for persons; creating a hostile atmosphere for migrants is therefore impermissible, even though deportation under conditions that avoid destruction may still be allowed. Yet the more intricate cases, such as refusing asylum to those fleeing conscription in unjust wars, expose the limits of Kant’s own resources. Here Mieth resists the temptation to force a definitive Kantian verdict. Instead, she marks the place where Kant’s teleological hope—that history will eventually produce a cosmopolitan legal order—runs up against concrete dilemmas of responsibility and resistance that his theory does not fully address.

In this refusal of premature resolution lies a final, clarifying gesture. The lecture does not simply apply Kant to present problems, nor does it merely catalogue his inconsistencies. It stages Kant’s cosmopolitanism as a field of tensions: between moral psychology and legal form, between the ethics of respect and the reality of war, between self-interest and solidarity, between the thin legal right to present oneself and the thick ethical demand to recognize every person as an end. By following the concept of hostility through these tensions, Mieth succeeds in making visible both the critical power and the structural fragility of Kant’s cosmopolitan right. The result is a contribution that is at once exegetically careful, conceptually original, and politically incisive, precisely because it allows the unresolved questions to stand as part of the truth of Kant’s project.