1. Globus terraqueus as a conceptual framework for Kant’s political cosmopolitanism

Why are there political communities on the blue marble that is planet Earth, rather than not? In Kant’s political philosophy, we can find an interesting, albeit mostly neglected answer: because of the spherical shape of the earth, it is inevitable that individuals meet each other. Upon this initial meeting, it is likewise inevitable that people form social communities which turn into legally and politically consolidated entities. The thought experiment of globus terraqueus, which in Kant’s idiom refers to the roundness of the globe and being covered by earth and water, is the conceptual framework for his political cosmopolitanism, connecting the spherical shape of the earth precisely with community and commercium.

It is astonishing to note that there are few engagements with Kant’s notion of globus terraqueus. Take, for example, Arthur Ripstein (Reference Ripstein, Himmelmann and Serck-Hanssen2022), who uses ‘globus terraqueus’ in the title for a lecture at a recent Kant Congress but quite tellingly does not engage with Kant’s metaphor in the body of the text. Central recent commentaries, such as Byrd and Hruschka (Reference Byrd and Hruschka2010: 127), do not further elaborate the wording of Kant’s metaphor. What is striking, however, is that Kant uses it as a geographical metaphor in the context of political theory. Cultural theorist Diane Morgan (Reference Morgan, Sarat, Douglas and Merrill Umphrey2014: 142–3) argues that Kant uses the technical-physical terminology of globus terraqueus as a reminder of the limitedness of the globe. Acknowledging limited space and, thus, limited resources, Morgan hints, is Kant’s attempt to avoid the category of cosmopolitan right drifting off into mere speculation. Of course, it is not entirely surprising that Kant uses a geographical metaphor. In fact, geographical metaphors and compound uses of the word ‘world’ (Welt-) are frequent and wide-reaching in Kant’s philosophy (Salikov/Sturm/Zhavoronkov Reference Salikov, Sturm and Zhavoronkov2025). Kant’s long-lasting lectures on Physical Geography speak to his deep familiarity with geographical issues (cf. Buchenau Reference Buchenau2023: 191–7). However, it remains puzzling why Kant utilizes the metaphor of globus terraqueus within the confines of his political cosmopolitanism.

To answer this puzzle, this article advances a relational reading of Kant’s political cosmopolitanism. Starting from his social theoretical notion of ‘unsociable sociability’ in the Idea for a Universal History (1784), this article argues that Kant’s cosmopolitan relationality is conceptually finalized in the notion of globus terraqueus through which he brings together earlier notions of temporal and spatial cosmopolitanism and conceptions of an a priori creation of legal communities. This argumentation thus situates the contemporary literature on Kant’s political cosmopolitanism and bridges various strands of his thought (Huber Reference Huber2022; Massimi Reference Massimi2023; Milstein Reference Milstein2013, Reference Milstein2015; Pinheiro Walla Reference Pinheiro Walla2016, Reference Pinheiro Walla2026; Taraborelli Reference Taraborelli2019). For example, Jakob Huber (Reference Huber2022), who is building on Byrd (Reference Byrd and Denis2010: 107), has grounded Kant’s cosmopolitanism by starting from ‘earth dwellers’. I further this approach by taking Kant’s notion of globus terraqueus seriously. By shifting nuances in recent interpretations, such as the common possession of the earth, which is the logical endpoint of Kant’s cosmopolitanism as an apriori legal space (cf. Huber Reference Huber2022), this article argues that globus terraqueus is the conceptual framework which ties cosmopolitical notions such as the spherical shape of the earth, community, and commercium together in a relational manner. Kant’s political cosmopolitanism is, thus, held together through a conceptual bracket in a kind of cosmopolitan relationality which is characterized by the components of agency, conflict, and vulnerability.

The article starts by outlining the sources of Kant’s cosmopolitan relationality and its components of agency, conflict, and vulnerability based on a reading of his Idea for a Universal History essay (section 2). Then follows a detailed discussion of references to the global shape of the earth, original common possession, and argument from earth dwellership in the Metaphysics of Morals and recent interpretations (section 3). On this basis, the central contributions of this article are elaborated by carefully reconstructing §62 of the Metaphysics of Morals, in which the sole reference to globus terraqueus is found (section 4). In section 5, the components of Kant’s cosmopolitan relationality are then applied to the recent debates about the content of cosmopolitan right in the notion of universal hospitality. Section 6 concludes.

2. Sources of relationality: agency, conflict, vulnerability

We begin where Kant first mentions cosmopolitanism in the essay Idea for a Universal History, in which he introduces the social theoretical concept of ‘unsociable sociability’ (ungesellige Geselligkeit) (IUH, 8: 20).Footnote ¹ Unsociable sociability is not only to be seen as a basic human condition or a social phenomenon with which humanity has learned to cope. Unsociable sociability, on my reading, does not even strictly presuppose specific views of human nature. Rather, I take Kant’s conception of social antagonism to refer to conflict as a feature of how individuals and groups relate to each other. On this reading, unsociable sociability is the driving force of Kant’s first conceptual articulation of cosmopolitanism. I argue that unsociable sociability prompts three components of relationality – agency, conflict, and vulnerability – which can be utilized as a starting point to reinterpret Kant’s cosmopolitanism. In highlighting these three components, this interpretation avoids essentialist assumptions about human nature but rather points to practical features characterizing humanity. Recall how Kant introduces the concept:

Recall the context of the essay. The central aim for Kant in this essay is to reconcile a teleological view of nature with the autonomy of human agents. Granting humans agency – and thus, all kinds of human freedoms, such as freedom of choice, decision, and belief, or values – is hard to square with natural teleology because humans are part of nature too and because humans are drawn to make mistakes, either unintentionally or willingly. In a way, Kant addresses the ambivalences between nature and culture. In this opening statement to the fourth proposition in Idea, Kant introduces unsociable sociability to bring this ambivalence to adequate terms. The antagonism in society is a driving force and mechanism in which humans develop ‘their lawful order’. Antagonism is a mechanism in which human needs and inclinations enter conflict. Humans need interactions with others; that is what Kant calls to ‘enter into society’ (in Gesellschaft zu treten), and they also need to be left alone, or as Kant says, humans wish to be ‘individualized (isolated)’ (IUH, 8: 21). Quite remarkably, taken together, Kant describes this as ‘inclination to be socialized’ (Neigung sich zu vergesellschaften) (IUH, 8: 20).

This ambivalence can also be described as the component of conflict in relationality. In Idea, Kant is in the business of identifying mechanisms that make plausible that history and nature are continuously progressing. Of course, this kind of faithful optimism is rather unplausible today. However, for Kant, this optimism is rather an expression of a belief in the values of the emerging modern sciences. Conflict, as it is expressed through Kant’s concept of unsociable sociability, is a speculative example of identification of mechanisms in nature in which humans do interfere.

According to Kant, unsociable sociability is based on the predispositions of human nature (Anlagen der menschlichen Natur) (IUH, 8: 20). However, the predisposition of unsociable sociability does not rule out agency. Otherwise, the driving force which Kant ascribes to conflict in history and society would be at a standstill. Therefore, I take Kant to grant humans agency in their own life chances.Footnote ² An example is that Kant argues that humans seek concord (Eintracht), but that nature delivers discord (Zwietracht) (IUH, 8: 21). Notice that Kant is mostly arguing about individual dispositions or attitudes for action and not necessarily about dispositions in the whole of humanity. This is remarkable because by analogy the adversary of each individual is nature itself. The following exposition drives this observation home: a human ‘wills to live comfortably and contentedly; but nature wills that out of sloth and inactive contentment he should throw himself into labour and toils, so as, on the contrary, prudently to find out the means to pull himself again out of the latter’ (IUH, ibid.). This argument by Kant shows the entwinement of human action and an alleged human nature, which is posed negatively here as sloth and contentment. Therefore, I follow Williams (Reference Williams1983: 8) who stresses that Kant thinks that abilities and capacities are strengthened within society and through interaction with others.

Further textual evidence for my relational reading is found in the fifth proposition which follows the initial exposition of the concept of unsocial sociability. Kant argues that the conflict through which unsociable sociability leads agents will eventually cause a change in the social structures in which agents find themselves. There, Kant argues that the biggest problem for the human species is the question of how to administer justice universally to build and maintain a just civil constitution (IUH, 8: 21). This leads him to imagine a ‘cosmopolitan condition’ (IUH, 8: 28). My relational reading argues that here Kant is neither solely proposing some epistemological or individual predispositions to express cosmopolitan sentiments, nor only putting forth a rationally valid proposal for a universal institutional design, but rather referring to how people behave and act and expect to be treated.

Expectations and realities of human interaction diverge. This brings the risk of being injured into view. Therefore, the component of vulnerability needs to be addressed. That vulnerability is in the background of Kant’s views on cosmopolitanism is plausible when highlighting a closing thought from Perpetual Peace:

Vulnerability of agents is in the background of this passage because Kant acknowledges that violations of rights might occur anywhere at any time. Vulnerability is, therefore, a social phenomenon in the political and social life of individuals regardless of place or social position. Note that Perpetual Peace was written by Kant with a public audience in mind. This is reason enough to think that the rhetorical structure of this concluding statement is part of Kant’s argument. Kant ties progress towards perpetual peace to an acknowledgement and redress of violations of right. As a response to these violations, Kant argues that cosmopolitan right is a convincing mechanism to address violations and to protect individuals anywhere. The feature of vulnerability sits in the background here because as long as humans are living among each other, there is potential to violate others’ rights and to injure one another.

In drafts and notes, which Kant wrote as preparation for his treatise on peace, we find another interesting and related passage: ‘A spark of a violation of human rights suffered in another continent, in accordance with the flammability of the material of thirst for power in human nature, above all in their leaders, lights the flame of war that reaches the region where it had its origin’ (Kant Reference Kant2016: 223; 23:175).Footnote ³ Furthermore, the formulation found in the drafts does not only directly resemble the ‘violation of rights’ formulation which Kant ultimately uses in his Friedensschrift, but rather this is an instance in which he merges anthropological assumptions with a naturalistic metaphor for a political-theoretical purpose. Kant uses natural metaphors – spark, flammability – to say that violations of human rights negatively indicate a mechanism that points to something akin to human nature. If this were a statement about human nature, it would be much more backhanded than Kant usually formulates such things. Hence, it seems valid to relate the emphasis in both violation-formulations to the fact that violations need to have been actively committed by an agent through measures of conflict. Therefore, I have distilled a conception of relationality with the features of agency, conflict, and vulnerability from this initial discussion in Kant’s Idea.

Of course, vulnerability is not a uniquely Kantian feature in ethics or political theory. Vulnerability has been recently taken up in feminist thought as a relational and ethical concept (Mackenzie/Rogers/Dodds Reference Mackenzie, Rogers and Dodds2013). Formosa (Reference Formosa, Mackenzie, Rogers and Dodds2013: 88–109) has highlighted the role of vulnerability in Kantian ethics. These recent efforts show that to be vulnerable means to be susceptible to harm, injury, or misuse (Formosa Reference Formosa, Mackenzie, Rogers and Dodds2013: 89). Both individuals and social groups are vulnerable. Children may be perceived as especially vulnerable and even dependent on their social surroundings, whereas states are both vulnerable and tend to perpetrate atrocities. Furthermore, these contemporary observations lead to the construction of a distinction within the component of vulnerability. Namely, vulnerability as a relational feature in conflicts of agents can either be understood as vulnerability to harm or as vulnerability to a violation of rights. This distinction will prove to be useful in the ensuing reconstruction of universal hospitality.

My proposed reading of Idea has a different thrust than that of most commentators who take this passage to prepare the way for Kant’s later anthropology. My conceptual rendering of unsociable sociability is aimed at making plausible that Idea provides a conceptual starting point for developing Kant’s cosmopolitan relationality – through the components of agency, conflict, and vulnerability. Most commentators view the concept of unsociable sociability as a preparatory statement of Kant’s anthropology or in direct reference to his view of human nature (Nehring Reference Nehring, Willaschek, Stolzenberg, Mohr and Bacin2015a, Reference Nehring, Willaschek, Stolzenberg, Mohr and Bacin2015b; Guyer Reference Guyer, Rorty and Schmidt2009; Wood Reference Wood1991, Reference Wood, Rorty and Schmidt2009). Contrary to this standard manner of connecting unsociable sociability with anthropological commitments and civilizational progress, interpreters like Darwall (Reference Darwall2014: 203, 215–16) argue that ‘sociability’ can be understood as a second-personal relation. However, my conceptual rendering of unsociable sociability is not meant as a full-fledged counterargument to the prevailing opinions of Kant interpreters. Rather, I reconstruct central textual evidence which gives initial suspicion towards identifying Kant’s notion of the globus terraqueus as a conceptual frame for his view of cosmopolitan relationality.

3. Dwelling on the spherical surface of the earth

Before addressing Kant’s conceptions of cosmopolitan right in his late writings in the Doctrine of Right and Perpetual Peace, it will be useful to flesh out some connections between Kant’s arguments regarding property and his cosmopolitanism. Doing so strengthens the case for the importance of relationality for cosmopolitan thought. Recall Kant’s argument regarding property in the state of nature. Ownership of external things in the state of nature is, according to Kant, only possible in the form of possession. There are no strict guarantees for ownership claims in the state of nature, where possession of property can only be valid provisionally.Footnote ⁴ A civil condition, however, can adjudicate rational and legal claims to possession. Kant conceives of property inherently as a relationship, but not as a relation between a person and a material good. Rather, Kant conceives of property as a relation between persons that organizes access and claims to goods, both materially and noumenally. Oliver (Reference Oliver2014: 23–4) argues that Kant’s cosmopolitanism is an offshoot of his relational account of property. Kant’s cosmopolitanism, according to Oliver, outlines conditions of possibility of commercial and juridical relations between individuals and nations making claims to property. Kant makes these metaphysical claims, Oliver argues, on the basis of two facts, namely that the earth is a sphere or a globe and that ‘all human beings live on this same planet’ (Oliver Reference Oliver2014: 24). The spherical shape of the earth, thus, is the (meta-)physical condition both for Kant’s theory of property relations and his cosmopolitanism.

There is, however, a different argumentation ongoing where Kant connects the idea of original common possession implicit in this notion with his own cosmopolitanism. This connection is highlighted by Huber’s (Reference Huber2022: 137) ‘argument from earth dwellership’, which refines Kant’s political cosmopolitanism. Huber’s reconstruction of the idea of earth dwellership’ starts from §13 in the Rechtslehre:

This passage presents, for Huber (Reference Huber2022: 4–6), the textual evidence for Kant’s grounded cosmopolitanism. Two features of §13 are especially interesting to discuss here in more detail. On the one hand, ‘original possession in common’ has cosmopolitan implications. On the other hand, Kant’s reference to the ‘spherical surface of earth’ reappears verbatim in his conceptualization of cosmopolitan right in §62 of the Rechtslehre.

Huber highlights that humans are agents who are corporeal beings grounded on the earth: ‘human beings are not only morally accountable, but also physically embodied agents who necessarily act in time and space’ (Huber Reference Huber2022: 20). Huber, who in turn follows Sharon Byrd (Reference Byrd and Denis2010: 107)Footnote ⁵ , calls embodied agents ‘earth dwellers’ who are ‘corporeal beings who have to share the earth in common with a plurality of agents of the same kind and who (unlike lions, rabbits, and bees) are able to grasp the normative implications of this fact’ (Huber Reference Huber2022: 20). The idea of earth dwellership, as Huber argues, grounds relations of possessions as they matter to agents on a limited and finite space of the earth. From this possession-based argument, he reconstructs an innate right to be somewhere (Reference Huber2022: 22ff.).Footnote ⁶ Kant brings out a related thought that is a hallmark in contemporary cosmopolitan political thought: the moral contingency of one’s birthplace. Cosmopolitans today argue that because of this necessity, borders do not matter morally speaking. Kant addresses this in his drafts in preparation for his legal and political philosophy:

Being born somewhere gives someone a right to be there and puts them in a relation of right with the place they happen to be in. Thus, everyone is an occupant, or as the German original says Inhaber, which connotes that you are responsible for the upkeeping of this spot. Kant continues by emphasizing that everyone needs to be somewhere:

Kant focuses on the idea of landing somewhere involuntarily. Starting or ending up somewhere involuntarily is not supposed to bring anyone negative consequences. This broad claim is cosmopolitan as it is a claim which is universally applicable.

A final note is in order before moving on to the discussion of Kant’s specific notion of cosmopolitan right. As Kant says in §13, the lands of the earth constitute original possession in common. In the drafts we also find the following, perhaps even more succinct, statement: ‘All human beings on earth are in an original community of possession (communio originaria) of the surface of the earth as a whole, the extent of which is determined and is incapable of enlargement’ (23: 322; Kant Reference Kant2016: 317). As the earth is limited in extension, and thus incapable of being enlarged, everyone initially shares possession of the earth. Huber (Reference Huber2022: 31ff.) reconstructs from this original possession in common the idea of ‘constructing right in an a priori space’:

Huber argues that it follows from the right to be somewhere, and the connected original possession in common, that Kant constructs right from an a priori point of view. This establishes juridical relations in general.

In the remainder of this article, I aim to connect the components of relationality established above with the cosmopolitan upshot that I take to follow from these ideas of common possession, the right to be somewhere, and the establishment of judicial communities in an a priori space. The proposed reading of relationality in Kant argues that attention to relations of conflict, commercium, and vulnerability are needed to refine metaphysical justifications of the genesis of rights on the globus terraqueus. In particular, it is crucial to see that Kant’s argument regarding the globus terraqueus does not merely hinge on the hypothetical first contact of creating legal communities but rather seeks to conceptualize what might happen next. In this sense, temporal and spatial perspectives overlap in Kant’s political cosmopolitanism. Thus, Kant’s cosmopolitan relationality moves forward through conceptualizing cosmopolitan right on the ‘spherical surface of the earth’ as the a priori space of universal hospitality.

4. The spherical surface of the earth and cosmopolitan right

The second part of the Doctrine of Right is concerned with public right, of which there is a tripartite structure. Section one deals with The Right of a State (Staatsrecht) (MM, §§43–52); the second with The Right of Nations (Völkerrecht) (MM, §§53–61); and the third is entitled Cosmopolitan Right (Weltbürgerrecht) (MM, §62). This third section is merely two pages long but is central to Kant’s international political theory. It contains only a single numbered paragraph. Kant’s brevity leaves quite a few questions open which are important for this article.

To open this decisive paragraph, Kant calls peace a Vernunftidee (idea of reason), which for Kant implies that peace needs to be grounded in a juridical relationship and cannot be achieved merely through philanthropy or ethics:

In the previous section, we already encountered the turn of phrase ‘spherical shape of the earth’ (MM, 6: 262). Kant argues that there is no universal legal community possible without the spherical shape of the earth. If the earth were an unlimited plane, people would not find it necessary to form binding kinds of legal communities. They would mingle amongst each other when it pleases and avoid any further interaction when it is a nuisance. Thus, the spherical limitation of the planet creates conditions not only for people to live together but also to live in universally administered ways.

Recall the postulate of public right from §42 of the Doctrine of Right, which says that it is a rational and legal duty to create a just civil condition when and where avoiding others is not possible. These two components, the spherical shape of the earth and the postulate of public right, ground the claim that cosmopolitanism is going to have ‘to do with rights’ rather than with philanthropy.

Another striking feature is of course Kant’s notion of globus terraqueus. In fact, it is the only time that Kant uses this term. Globus is Latin for ball, sphere, and globe. Terraqueus is derived from the words for earth and water. Kant uses other adjacent terms such as Kugelgestalt, Kugelfäche, and Erdfläche more often. Kugelgestalt quite literally refers to the shape of the earth (De Bianchi Reference De Bianchi, Willaschek, Stolzenberg, Mohr and Bacin2015a: 520; Reference De Bianchi, Willaschek, Stolzenberg, Mohr and Bacin2015b: 520–21). However, these terms are almost exclusively used in contexts of the natural sciences or geography. Kant only uses Kugelgestalt once more in a context of history when reviewing Herder’s Ideas on the Philosophy of the History of Humankind (1784–1791), where Kant notes that Herder uses natural phenomena to construct a theory of human history – a theoretical move not unlike Kant’s.Footnote ⁷ The context in which Kant uses the term globus terraqueus is, therefore, unique. The fact that the shape of the earth has a political and social function is quite remarkable.

The globe represents a totality. A whole is a relational framework. For Kant and his contemporaries, the thought that earth is round is familiar, but drawing moral, legal, and political conclusions from it is a novel feature in Kant’s political thought. Following the remarks about the spherical surface of the earth, which is the spatial condition of creating a social community, Kant returns to already familiar arguments regarding property:

Whereas the spherical surface of the earth grounds the social community and rationally leads into a more just civil condition, it is the possession of external things which creates a legal community. However, Kant introduces another kind of community. A community of interaction (Wechselwirkung) in commercial relations:

The issue of commerce and Kant’s notion of commercium hold some ambivalences (Milstein Reference Milstein2013, Reference Milstein2015). However, what I wish to highlight within the confines of the argument here is the explicitly relational feature which Kant brings to the fore in this sequence of his elaborations of cosmopolitan right. ‘Offering to engage in commerce’ is exactly an offering to enter a relation of mutual benefit with some other, potentially a stranger, be it in a local civil society or in unknown lands. This channel of interaction must be open without being met instantly with hostility or adversity.

This exposition of this central feature of Kant’s conception establishes that cosmopolitan right creates different kinds of relational frameworks which are, for lack of a better term, institutionalized through formal and habitual communities. Kant refers to social, legal, and economic communities as such relational frameworks. He brings these together in §62 to show in which kinds of relational scenarios individuals might find themselves. A cosmopolitan rightful community is one of manifold relationships. In synopsis, these kinds of relational frameworks show why recognition of cosmopolitan right is recognition of a rightful relationship and not merely a matter of a philanthropic attitude, a humanitarian view, or charity. At the end of the day, Kant thinks of these relational frameworks as creating claims of individuals against each other: ‘This right, since it has to do with the possible union of all nations with a view to certain universal laws for their possible commerce, can be called cosmopolitan right (ius cosmopoliticum)’ (MM, 6: 352).

5. Hospitality as cosmopolitan relationality in practice

The task of this article is to show that the trifold relationality of agency, conflict, and vulnerability is a central feature within Kant’s cosmopolitanism. With the following discussion of Kant’s idea of universal hospitality within his specific conception of cosmopolitan right, we in fact arrive at the conceptual content of Kant’s notion of cosmopolitan right. My argument is that, precisely at this point, it is helpful to interject the relevant components of relationality – agency, conflict, and vulnerability – into the conceptual content of Kant’s political cosmopolitanism in the notion of hospitality. In this respect, I think that Kant’s formulation in Toward Perpetual Peace takes systematic priority over the lead-up and construction of the argument in the Doctrine of Right which was published two years later. Furthermore, I hold that the formulation of cosmopolitan right as found in §62 of the Doctrine of Right and the third definitive article in Toward Perpetual Peace are compatible and function complementarily. The third definitive article reads: ‘Cosmopolitan right shall be limited to conditions of universal hospitality’ (TPP, 8: 357). This axiomatic statement is elaborated in detail. Kant again distinguishes philanthropy from cosmopolitan right:

The analogy of hospitableness and right is quite irking.Footnote ⁸ Contrary to common-sense intuitions, which would promote hospitable behaviour on the basis of ethical inclinations, Kant describes hospitality by reference to a negative right of expecting not to be treated with hostility when arriving elsewhere. The corresponding negative duty, from the point of view of the greeting parties, extends to anyone who ‘has arrived on the land of another’. As Owen (Reference Owen2022: 154–5) argues, hospitality can be conceptualized both in terms of ethics and of right. Hospitality as a matter of ethics is situated on the interpersonal level and is first and foremost an ‘attitude towards others’ and a way of standing to the other that ‘expresses one’s acknowledgment’ (Owen Reference Owen2022: 154). By contrast, Kant provides the conceptual innovation of understanding hospitality as a right. As Owen (Reference Owen2022: 156) argues, Kant thereby transforms both cosmopolitanism and hospitality.

A recent debate within Kant scholarship is helpful to carve out the relationship between relationality, hospitality, and cosmopolitanism. This debate between Christopher Meckstroth, Pauline Kleingeld, and Peter Niesen – which is mediated and staged by David Owen (Reference Owen2022) – is essentially about the scope and content of Kant’s conception of hospitality. The scope of Kant’s conception has implications for the applicability of cosmopolitan right.

Meckstroth (Reference Meckstroth2018) argues that Kant’s conception of cosmopolitan right as hospitality does not entail any positively enforceable claims and rather is a purely negative category. As Meckstroth reconstructs Kant: ‘his right of hospitality was framed just so that it could never be invoked to start a new war in the name of pursuing one’s rights’ (p, 539). He argues against standard interpretations of Kant’s conception of hospitality to include some positive values. As Meckstroth would have it, hospitality and cosmopolitan right are categories critical of the cosmopolitan and natural law traditions. Meckstroth’s (pp, 543–4) reading of Kant’s reception of the ius gentium tradition from Grotius to Pufendorf and Vattel and others is characterized by the conceptual innovation of limiting cosmopolitan right and by redefining hospitality. As Meckstroth puts it: ‘Kant’s aim was not to add new rights, but to reformulate the traditional law of nations strictly on the basis of a demand for peace compatible with the consent of all subject to law’ (p. 544). He takes Kant to reinterpret the natural law tradition so as to prevent further justifications of colonial conquest and warfare (p. 550). Meckstroth has a restrictive view of the purpose of Kant’s third definitive article, namely, to rule out war as a legitimate strategy in international affairs. On this ground, cosmopolitan right does not need to be binding or coercive and does not need to be institutionalized. Cosmopolitan right, on Meckstroth’s reading, is sufficiently covered in international law and can be realized through the tools of adjudication of international law. Hence, Meckstroth limits the scope and applicability of cosmopolitan right as hospitality.

However, Meckstroth’s reading has some value from the perspective of a Kantian cosmopolitan relationality. Namely, Meckstroth’s purely negative reading of Kant’s notion of hospitality and the third definitive article show the indebtedness of Kant’s political cosmopolitanism to the value of harm reduction, or in our terms: vulnerability to harm. Cosmopolitan right, on Meckstroth’s reading of Kant, is a structural feature to reduce harm through mechanisms of international law on a diachronic basis. However, the other two components of relationality, agency and conflict, and with them a more synchronic perspective, are slightly neglected in this picture. In my view, Meckstroth’s reading of Kant’s cosmopolitan right overemphasizes the content of hospitality as cosmopolitan right over the form of vulnerability in cosmopolitan right. I think that shifting the emphasis on relationality in Kant’s conception of hospitality highlights the fact that cosmopolitan right hinges on a connection between content and form. In a relational reading of Kant’s cosmopolitan right and hospitality, vulnerability to harm and vulnerability to a violation of rights must be interpreted together. On Meckstroth’s account of hospitality, only vulnerability to harm would arise as an issue of international dispute. Violations of rights would be handled under the auspices of international law.

On the relational view which encompasses both vulnerability to harm and vulnerability to a violation of rights, Kant’s cosmopolitan right does not and cannot be subsumed under historical or even contemporary forms of international law: the normative content of cosmopolitan right creates the necessity to rethink the institutional landscape adjudicating the vulnerability of individuals and non-state peoples. Thus, hospitality and cosmopolitan right could not be handled under the auspices of international law. The content of cosmopolitan right needs to be put under consideration through different kinds of institutional settings.

Kleingeld (Reference Kleingeld2012: 73) takes Kant’s conception of hospitality to mean ‘somewhat surprisingly perhaps, that states and individuals have the right to request interaction with other states and their inhabitants, but not a right to enter foreign territory’. She aptly describes (p. 76) hospitality as the content of cosmopolitan right. This is formulated as a negative right and is conceptualized in a minimalist way which contains not to be treated with hostility as a foreigner (TPP, 8: 358). This amounts to what Kant distinguishes as Besuchsrecht (right to visit) as juxtaposed to Gastrecht (right to be a guest) (ibid.). Additionally, Kleingeld emphasizes (p. 77) that Kant defends the rights of non-state nomadic peoples. From the perspective of a Kantian cosmopolitan relationality, Kleingeld focuses on the dimensions of agency. The right to visit as content of universal hospitality and cosmopolitan right gives individuals and non-state peoples agency over their wellbeing when entering unsettled and dynamic legal situations.

In comparison to both Meckstroth and Kleingeld, Niesen presents the most far-reaching interpretation of Kant’s conception of hospitality in relation to the illegitimacy of colonial engagements. He argues that Kant’s conception of hospitality should be read in light of the critique of European colonialism and identifies cosmopolitan right as hospitality to entail ‘communicative rights’ (Reference Niesen2007: 91). Niesen shows (Reference Niesen2005: 209–15, Reference Niesen, Herlin-Karnel and Rossi2021, Reference Niesen2024: 153–55) that cosmopolitan right should be understood as subjective right which can be claimed against any state. He then proceeds to emphasize cosmopolitan right as a ‘communicative right’, which is a subjective and collective claim to interaction. Niesen concludes (Reference Niesen2007: 104): ‘Starting from the assumption that hospitality entails communicative rights and duties, I have identified legal rights and obligations that appear both more and less extensive than human rights to free communication’. However, Niesen argues that there is an aporia in Kant’s conception of cosmopolitan right because the ‘communicative entitlement to seek institutional access’ relies rather on Kant’s argument regarding the common heritage of humankind and not on original possession in common (Reference Niesen, Timmons and Baiasu2025: 210). On Niesen’s reconstruction, Kant misjudges the scope of his own conception of hospitality as it should provide more robust kinds of institutional access. Niesen (Reference Niesen, Timmons and Baiasu2025: 211–14) aims to reconcile these two sources of cosmopolitan right in Kant by proposing to provide institutional provisos to establish global rights of communication and mobility as safe corridors of passage and interaction. In the conceptual terms of this article, Niesen’s emphasis on hospitality as communicative right articulates the component of vulnerability to a violation of rights. With this emphasis, furthermore, the conflictive nature of hospitality becomes clear as well. Thus, it is the advantage of a Kantian perspective of cosmopolitan relationality to combine all three components of relationality.

When bringing these debates on universal hospitality as the content of cosmopolitan right together, we see that a Kantian perspective of cosmopolitan relationality might cover all the bases of the components of relationality. The components of agency, conflict, and vulnerability – which were reconstructed from the notion of unsociable sociability in Idea – help to illuminate the scope of cosmopolitan right as well as the conceptual content of universal hospitality. Recall that my argument is both to develop an account of Kant’s cosmopolitan relationality based on an interpretation of unsociable sociability and to show the compatibility of Kant’s renderings of cosmopolitan right in §62 of the Rechtslehre and the third definitive article in Perpetual Peace. Each of these texts brings decisive evidence with the notions of the spherical shape of the earth and universal hospitality as cosmopolitan right, respectively. The spherical shape of the earth creates, both in hypothesis and in reality, the conditions for human beings to enter juridical and social communities. What might happen next is answered in both the notions of unsociable sociability and universal hospitality. Vulnerable agents potentially enter conflicts over resources or standing. As real human beings we are vulnerable to harm, and as legal entities we are subject to vulnerability to a violation of rights. Through the joined forces of a relational perspective, the cosmopolitan dimension of Kant’s argument is emphasized. Universal hospitality, for Kant, applies to individuals and to non-state peoples. If non-state peoples would constitute themselves and their respective community as a state, then international law and not cosmopolitan right would be applicable on Kant’s view.

Relationality motivates the structure of Kant’s conception of cosmopolitan right and conditions the content of hospitality. Relationality is not limited to the ethical and common-sense view of hospitality but is a baseline for hospitality if it is codified as a subjective and collective right. Notions such as Inhabung or common usage are a further moment in which Kant ascribes relationality an important place in his cosmopolitan thought.