Kant’s notion of perpetual peace, first articulated in Toward Perpetual Peace Footnote 1 (TPP) in 1795, has attracted much attention as a guiding idea for interactions between states with a view to establishing lasting peace in the world. However, certain systematic questions still abound with regard to how this notion fits into Kant’s practical philosophy more generally. On the one hand, the definitive articles for perpetual peace do aim at establishing a legal-juridical condition that would obtain among states voluntarily entering into association with each other, and so the notion fits into Kant’s legal thinking. On the other hand, some aspects of perpetual peace make reference to Kant’s writings on history, anthropology, and teleology. Finally, in the Conclusion to the Doctrine of Right, perpetual peace is called both the ‘final end’ of Kant’s legal philosophy as well as the highest political good, bringing the text close to issues in moral philosophy proper. Indeed, in Section III of the Doctrine of Right, Kant calls perpetual peace the highest political good as well,Footnote 2 positioning the idea in some sense as the telos of his political thinking, which at first glance contradicts the common understanding of Kant’s moral philosophy as the formalist, anti-teleological ethics par excellence.
In this paper, I want to consider how the notion of perpetual peace might find a place systematically that is broader than the narrow legal concern of establishing a legal-juridical condition. The reason is to highlight the aspects of Kant’s thought that may have been overlooked in other accounts, and so to redress deficiencies in current interpretations of Kant’s arguments around perpetual peace. To do this, I will first consider Kant’s notion of the highest good, in order to set up a basic notion of his moral thinking that we can contrast with the notion of perpetual peace as the highest political good. Second, I will consider a variety of interpretations of perpetual peace in relation to Kant’s views on teleology. Third, I will argue that Kant’s views on teleology present an alternative that reconciles some of the competing desiderata from the interpretations considered. In particular, the metaphysics in Kant’s teleology implies a theory of international relations that is more ambitious than a mere solution to a coordination problem, as it lays out a view of the place of human freedom in a world determined by naturalistic causality. To do this, I will focus on a reading of one of the preliminary articles in TPP to suggest a more expansive understanding of perpetual peace as the highest political good. In conclusion, I will consider possible objections and offer replies.
1. Initial problem
The notion of perpetual peace is given a short characterization in the Doctrine of Right of the Metaphysics of Morals (MM) (1797) in the Conclusion to the Part on Public Right. To summarize, the prohibition on war comes with the idea of pursuing the establishment of perpetual peace, even if this may not be really possible. As long as it is not seen as impossible, we should consider ourselves under the obligation to establish constitutions most conducive to it. The final paragraph begins thus:
It can be said that establishing universal and lasting peace constitutes not merely a part of the doctrine of right but rather the entire final end of the doctrine of right within the limits of mere reason. (6: 355)
Kant is thus identifying the state of perpetual peace as the purpose or aim of the Doctrine of Right as a whole and as something for which we, as philosophers, require a metaphysics to have any grasp of how we ought more precisely to determine it for the sake of its pursuit. Notably, we should not attempt to establish it through a revolution, but rather through a process of gradual reform:
But if it is attempted and carried out by gradual reform in accordance with firm principles, it can lead to continual approximation to the highest political good, perpetual peace. (6: 355)
In one paragraph, Kant has thus identified perpetual peace as both the ‘final end’ of the Doctrine of Right and the highest political good. These terms bear closer scrutiny, as they reveal intersections with both Kant’s moral philosophy and Kant’s writings on teleology.
In essence, the problem identified seems to point to wider issues in Kant’s system. While the identification here (if real, rather than apparent) could seem innocuous, the implications are wide-ranging given how metaphysically weighty the notion of the highest good is in Kant’s moral philosophy, insofar as its metaphysical presuppositions are concerned. Further, given the indications that TPP offers a teleological argument for how the framework expressed in the essay would be instituted, if DR makes this identification explicit, it suggests that DR could be read within these broader considerations in favour of a more teleological reading of Kant’s political philosophy.Footnote 3
Before discussing the idea of perpetual peace further, I will first summarize relevant points on the idea of the highest good from Critique of Pure Reason (CPR) and Critique of Practical Reason (CPrR), as well as the relevant points on the notion of final purpose (Endzweck) in Critique of the Power of Judgement (CJ).
2. Highest good: preliminariesFootnote 4
Kant discusses the idea of the highest good first in the Canon of Pure Reason in the CPR, and then elaborates on it more precisely in the Dialectic of pure practical reason in the CPrR. In the Canon, Kant reflects on the ultimate endFootnote 5 of pure reason and finds its expression in three questions: ‘What can I know? What should I do? What may I hope?’ (A805/B833). In answering the third question, he develops the idea of the highest good, which here is the metaphysical conception of the world as ordered by moral laws in conjunction with the causal efficacy that we attribute to natural laws. As the object of our hope, our reason indeed conceives of an idealized world where the two different types of legislation at the disposal of reason are in some sense perfectly harmonized.Footnote 6 The highest good thus gives us a mould for what the world would be if happiness were determined in proportion to virtue, and, at least in the CPR, also an ideal to aspire to that is motivationally active in our pursuits.Footnote 7 The idea here is also that the highest good, when conceived of as an intelligible world, shows us that this world can also be brought about in nature, even though this goal might be quite difficult to reach, or even impossible in any finite term.
This line of thought is further taken up in the CPrR, with some important changes. Importantly, Kant introduces a further set of distinctions: (a) the original and the derivative highest good, and (b) the supreme and complete good.
Regarding (a), the distinction in fact occurs at three levels. Firstly, we distinguish the intelligible world, where virtue and happiness in every finite rational agent are perfectly distributed, and the ground of this world. Secondly, since this world is considered to be metaphysically possible through determinations of actions by the moral law, and since this does not include metaphysical impossibilities, the world we are considering can be realized or at least ever more closely approximated in the world of appearance. Thirdly, since we sometimes fail to act for the sake of morality and sometimes, even if we act morally, we fail to bring about the idealized world, the possibility of the moral world is grounded in a highest original good, i.e. God.Footnote 8 Considering now the distinction between the supreme and the complete good, we can distinguish the supreme good as virtue and the complete good as virtue combined with happiness.Footnote 9
With regard to the highest good, the distinction can be summed up, in part, with reference to the opening of Groundwork I: ‘It is impossible to think of anything at all in the world, or indeed even beyond it, that could be considered good without limitation except a good will’ (4: 393). Thus, happiness is only a good insofar as one does not violate the moral law. Happiness however, as the end of finite beings like ourselves, is not optional, although it is dependent upon particular people’s choices, but can only be a part of the highest good if conditioned by the supreme good, i.e. virtue.Footnote 10 In a sense then, happiness is only good if one deserves it,Footnote 11 and the highest ethical good, while springing from virtue as its pure part, since it requires only the determination of the pure will according to its principle, is only complete when one’s happiness comes as its concomitant.
Part of the difficulty when applying these different notions of the highest good to the notion of perpetual peace, as it fulfils different roles practically and systematically in Kant’s political and legal philosophy, is to see how all of these senses can come to bear in the notion. One could isolate one particular sense of the highest good, e.g. the highest good in the world as laid out in the CPR, as the interpretative key through which to understand the end state of ‘achieved’ perpetual peace that the framework aims at. However, given the difficulties in expecting humans to be motivated to move into this state, the framework of the highest good in the person seems to be equally applicable as an interpretative key for the notion of perpetual peace, even as the problem has been reconfigured from its original position as a problem in moral psychology to a problem in legal-political institution-building. What this paper aims to do is to pull together various strands of this idea, where other interpretations only engage with this aspect of Kant’s philosophy in a partial way, if at all.
3. Interpretations
In TPP, Kant lays out both preliminary and definitive articles towards achieving perpetual peace as a legal-political reality. Again, in chapter III of the Doctrine of Right, Kant calls perpetual peace the highest political good, positioning the idea in some sense as the telos of his political thinking. In isolation, this can appear strange, given that Kant’s practical philosophy is very often formulated in specifically formal, anti-teleological terms. Thus, morality is determined by a particular form of determining one’s will (the Categorical Imperative), and principles can only be instituted as law if they follow a strict principle governing external behaviour (in conformity with the Universal Principle of Right). What are the connections, or even similarities, between Kant’s moral and political philosophy with respect to the determination of perpetual peace as the highest good?
The notion of perpetual peace as the highest political good is articulated in the conclusion of the Doctrine of Right:
It can be said that establishing universal and lasting peace constitutes not merely a part of the doctrine of right but rather the entire final end of the doctrine of right within the limits of mere reason; for the condition of peace is alone that condition in which what is mine and what is yours for a multitude of human beings is secured under laws living in proximity to one another, hence those who are united under a constitution … if it is attempted and carried out by gradual reform in accordance with firm principles, it can lead to continual approximation to the highest political good, perpetual peace. (6:355, italics mine)
Not only do we conclude with an identification of the highest good with perpetual peace, but also it is identified as such because it is the ‘entire final end’ (6: 355, my emphasis) of what Kant believes needs to be treated in a doctrine of justice.
The position defended in this paper is that there is indeed a connection between the ends and the formal principles underlying the system Kant puts forward, which in the end is encapsulated in a sort of providentialism.Footnote 12 For those that accept some continuity or harmony between teleology and legal principles, three lines of interpretation are available: (a) draw on the formal elements of Kant’s theoretical philosophy to reconcile any seeming disparity, (b) treat perpetual peace as a technical goal to be achieved by using recognizably teleological aspects of human nature towards institutionalizing a legal-juridical order, or (c) explain perpetual peace as the highest political good with recourse to higher-order teleological notions. For the purposes of classification, I shall refer to (a) as formalist, (b) as technicist, and (c) as substantivist.
3.1. Formalism
I will call any view of the role of teleology in Kant’s political philosophy ‘formalist’ that emphasizes Kant’s rationalism, i.e. his focus on rational and, more importantly, formal principles in determining those normative principles that should structure political society.Footnote 13 Any formalist would thus take further resources from Kant’s practical philosophy to recast what appear to be substantive claims as purely formal claims or principles.
Sorin Baiasu (Reference Baiasu, Valentin and Shunzo2013) lays out a formalist account against other interpretations that exaggerate the similarities between perpetual peace, the highest political good, and the highest ethical good. First, a problem arises when we take the highest political good to involve two components, the supreme and the complete good, as in the case of the highest ethical good. Perpetual peace could very easily be treated as the supreme good, and thus the normative goal for our action, even though it might be in fact impossible to realize this, which in turn would generate a command that would be impossible to obey since it could not be fulfilled. Second, it is unclear whether interpreting perpetual peace as the highest political good also involves postulates like immortality or the existence of God, as in the ethical case, in order to guarantee the possibility of realizing perpetual peace. Third, if we understand perpetual peace as the result of deliberate action, the legal-juridical order that perpetual peace is to be characteristic of depends on the ethical motivation of the people bringing about this condition, which should not be necessary and which Kant denies explicitly in TPP (Baiasu: passim and esp. p. 16)
Baiasu resolves the tension in the text of the Doctrine of Right by understanding perpetual peace as an ideal to be striven for, but which functions as the supreme good, rather than as part of the complete good, which latter would still require a guarantee that perpetual peace is achievable. Systematically then, there is no place for a complete good in politics, as the Doctrine of Right is only concerned with the establishment of a condition, or state, of peace, structured according to juridical norms (Reference Baiasu, Valentin and Shunzo2013: 25–6).
In his discussion of the guarantee of perpetual peace, Luigi Caranti (Reference Caranti and Bacin2013, Reference Caranti2022) can also be classed as a formalist, to the extent that he interprets the guarantee as an empirical claim about the tendency for human societies to approach the state of perpetual peace. While Caranti does not engage directly with the question of perpetual peace as the highest political good, his discussion of the guarantee of perpetual peace is instructive. Kant presents the guarantee as an empirical claim about the ordinary course of events, where humanity will, over time, institute this condition, as nature has implanted certain tendencies in humanity that, while causing war and conflict in the short term, will eventually impel us to seek peace. Obviously, certain problems come up with such a proposal, epistemic, moral, and anthropological. Caranti (Reference Caranti2022) resolves the epistemic difficulties by showing that (1) the relatively weak claim that Kant makes gives us good grounds for believing that we can and will succeed in approximating the condition of perpetual peace and that (2) these grounds are straightforwardly derivable from empirical-historical generalizations about human behaviour:
There may be strictly speaking no guarantee that perpetual peace will ever be reached, but there is a guarantee that the world, at least the world as we know it now, is objectively ‘biased’ in favor of an infinite approximation toward that outcome. (Reference Caranti2022: 29)
The apparent moral difficulty concerns the problem of mooted motivation, that we may perhaps lack the motivation to actually pursue perpetual peace if it will happen regardless of our action. Again, this can be dispelled fairly easily: ‘Even if perpetual peace will happen anyway, there is still a duty on our part to realize those institutional reforms that will speed up the process’ (Caranti Reference Caranti2022: 29). Finally, the anthropological worry is dispelled by pointing out that the radical evil in humanity would still not be able to contradict what is recognizable through the use of understanding, i.e. that peace serves the interests of individuals and groups better in the long run than war.
One problem that may arise out of this interpretation is that Kant may, in fact, intend a much stronger claim than the fairly weak empirical claim that Caranti puts forward. The guarantee is supposed to offer us assurance that we can (a) act in accordance with moral principles and (b) expect our endeavours (including realizing perpetual peace) to be realized in the world. Thus, Kant’s claim demands more of perpetual peace than that it will, at some indeterminate point in the future, be realized.
3.2. Technicism
I will call any view technicist that interprets Kant’s teleology with regard to human nature in terms of the question of how teleological principles are to be used for applying legal principles. This view sits between formalism and substantivism to the extent that it reinterprets Kant’s appeal to teleological principles as part of an understanding of the historical-empirical process of the development of legal institutions as natural processes that find their fullest expression in a legal framework whose validity is to be seen in ultimately formal terms.
Katrin Flikschuh (Reference Flikschuh and Bird2006) considers the teleological aspects of Kant’s arguments from the standpoint of how a legislator would institute the required framework for perpetual peace rather than a more metaphysically substantive understanding of how natural teleology produces that order. In effect, natural teleology here functions more like a resource in the toolkit of a wise legislator, coaxing, or even influencing imperfect agents to observe at least the legal-juridical norms under the principle of universal right. Her interpretation can proceed like this because the more substantive language (regarding teleology and metaphysics) is either dismissed or treated as obscure (pp. 386, 389).
Additionally, Flikschuh characterizes Kant’s invocation of nature as a providential guide as immodest: ‘Given the immodesty of invoking the idea of providence in the context of a nonreligious inquiry, we should continue to use the term “nature” – presumably “mechanical nature”’ (Reference Flikschuh and Bird2006: 389). The inquiry may perhaps be nonreligious, but that does not make it any less serious, particularly since the matter worked towards is an object of sincere hope. However, on top of Kant’s references to providence, Kant even manages to cite the Gospel of Matthew twice in the Appendix relating to the place of morality in politics (8: 370, 378),Footnote 14 neither reference seeming to indicate a dismissal of the object of this hope.
More seriously, Flikschuh’s interpretation relies on an account of natural teleology in Kant as justifying our obligation to institute legal frameworks that can realize a condition of Right. Since we have a retrospective account for how this happens, we also have some prospective account and subsequent justification for putting into place certain sorts of laws rather than others (Reference Flikschuh and Bird2006: 387–93). The problem with this view is that Kant offers very little as to how we should proceed in institutionalizing legal frameworks. Furthermore, the retrospective view does not offer a clear prototype to emulate, as Kant views law as the failure of unilateral imposition or as a risk-mitigation strategy in commercial relationships.
A later paper (Flikschuh Reference Flikschuh2007) takes up the same topic with regard to the argument in Theory and Practice III to show that Kant’s views were evolving over time, starting with more teleologically laden language, ending with the mature, formal framework of the DR.Footnote 15 In summary, Flikschuh claims that ‘from the search for moral intention in nature, Kant gradually moves to the employment of a law of nature as supplying a sensible schema for the construction of the non-sensible law of Right’ (p. 241). The main thrust of the argument remains the same: nature provides a certain mould that we as free moral agents need to formalize if we are to put laws of Right into place towards building the institutional frame for justice. While it appears to offer an interpretation of Kant, who progressively becomes more formal-rational in his approach, including his emphasis on free human agency, it does not seem persuasive when considering that Flikschuh can only cite two late works (the DR and the CF) to show this progression (where TPP still assigns a substantial role to natural teleology in the establishment of peace). Further, the methodology in the DR does not straightforwardly offer schemata of natural laws to formalize the laws that will institute justice in society, and so the interpretative problem persists.Footnote 16
In ‘Kant’s Political Zweckmässigkeit’ (Reference Huseyinzadegan2015), Dilek Hüseyinzadegan takes Kant’s use of some metaphors drawn from political life in the Critique of the Power of Judgement as indicative that the notion of teleology not only applies to organizing scientific disciplines, like biology, but also applies to characterizing human social life. Kant’s use of different analogies, contrasting a just state as a living organism with a despotic state as a handmill, and his understanding of teleology can be readily applied to political notions, including perpetual peace. Hüseyinzadegan writes:Footnote 17
I argue that [the principle of political Zweckmässigkeit] is a complementary principle of politics, which together with the principle of right, constitutes the whole range of his political thought. (Reference Huseyinzadegan2015: 422)
Hüseyinzadegan turns then to the First Supplement of TPP and the chapter ‘Cosmopolitan Right’ in the Doctrine of Right to argue that these passages show that Kant uses purposiveness as the material principle guiding how we are supposed to implement the formal principle of right so as to make perpetual peace empirically possible:
[T]he principle of political Zweckmässigkeit, as the material principle of politics, ‘necessitates only if the empirical conditions of the proposed end, namely of its being realized, are presupposed…’ (TPP, 8: 377). Thus ideals of political thought have both practical necessity, insofar as they are deduced from the principle of right, as well as a natural necessity, insofar as their feasibility is deduced from the principle of political Zweckmässigkeit. (Hüseyinzadegan Reference Huseyinzadegan2015: 437 ff)
Two problems present themselves here. First, the form/matter distinction here is misleading, given that political purposiveness is still only represented in reflection as a form of causality, namely, that of an analogically regarded agential causality. This is intelligible only if nature is the ‘agent’ in this process, which Hüseyinzadegan does not seem to subscribe to. Second, as Baiasu (Reference Baiasu, Valentin and Shunzo2013) has argued, there is neither need to include further moral qualifications in what motives are operative in the pursuit of perpetual peace, nor any need to appeal to nature’s indirect role in bringing about perpetual peace or how it will be institutionalized, since perpetual peace should be possible merely from practical freedom, and so considerations of how causation may figure into perpetual peace are only of technical interest in how peace can be institutionalized.
3.3. Substantivism
The substantivist view broadens the interpretative scope of Kant’s legal and political philosophy to accommodate some of the historical, anthropological, and teleological views that Kant articulates in other writings. In some sense, a substantivist treats Kant’s political philosophy as significantly shaped by his teleological, even metaphysical, views.
Robert Taylor (Reference Taylor2010) offers one such account that tries to find the continuity between the various segments of Kant’s practical philosophy. He highlights that some of the differences and discontinuities between different parts of Kant’s philosophy, particularly Kant’s ethics and politics, can be reconciled by further considerations of Kant’s philosophy of religion. While the ethical highest good offers the standard for human action, perpetual peace is a concrete proposal that can be measured in terms of continuous improvement and reform. Perhaps we cannot discount a gradual approach towards the highest good, but it is certainly more difficult to measure given the noumenal qualities involved (cf. 8: 386). Perpetual peace as the object of our strivings, while also being in some sense under the guidance of a providential teleology, is outside of our control. The main warning Kant thus offers is that we not be too quick to interpret certain signs of external progress as signs of moral progress. External progress may be necessary, but it is not sufficient for real moral progress. However, Taylor views Kant as arguing for ‘the fundamental similarity of perpetual peace to the highest good, a relationship so close that the former is contained by and serves as a precondition of the latter’ (p. 10).
Another prominent example can be found in Lea Ypi’s writings, which very explicitly tries to draw out the systematic coherence of Kant’s views, including drawing on lines of argument from the CPR and the CJ to bring these to bear on his practical philosophy. The most important role that teleology plays here is to give a goal towards which humanity as a collective will develop. Thus, the progress of human political collectives is the product of a ‘rational, collective agency embedded in cultural and political institutions promoting humanity’s moral ends’ (Ypi Reference Ypi2010: 121). Ypi acknowledges that this proposal cannot account for all of the elements of Kant’s philosophy, but that the virtue of this interpretation rests in integrating Kant’s political proposals with the results of the critical philosophy and thus giving a teleological understanding of historical progress rather than a mere technic of nature for producing political culture:
Politics, however, has a more complex task than simply that of framing institutions compatible with calculative principles. It must help transform the enlightened self-interests of individuals into genuine moral principles; it must promote not just ‘peace’ but rather ‘perpetual’ peace. (Ypi Reference Ypi2010: 123, my emphasis)
Ypi sees Kant in TPP as solving two problems of unsocial sociability in relation to the highest good. First, coordination is the demand that everyone be able to realize the highest good in this world, thus coordinating a perfect virtue with the corresponding distribution of happiness. Second, continuity is the demand that it be in some sense possible, even though we are temporally limited in the development of our moral disposition. Where the CPrR gives metaphysical postulates to guarantee this, Ypi argues Kant’s later political thought focuses on realizing the highest good through historical progress.Footnote 18
While this account has its strength in giving a clear role for natural teleology to influence our behaviour, Ypi arguably misrecognizes what the ‘final end of the world’ (CJ, 5: 434) is. In the Critique of the Power of Judgement, Kant points out that nature’s purpose, considered reflectively, is to bring about a species that is capable of morality, through the culture of skill and, more importantly, discipline. Thus, the purpose of the world would be realized if, in the end, only one human being were able to instantiate the highest good, i.e. to live perfectly according to the moral law and to have happiness awarded in perfect proportion to that virtue. Even when the moral politician steps in to legislate in favour of morality and against the state’s (or whichever group’s) self-interest, the moral politician has a different goal than Ypi’s interpretation gives us:
[Regarding the activity of the moral politician,] [a] transformation of political institutions as a function of an effective and uninterrupted development of morality requires ensuring that what human beings have collectively achieved throughout history is not undermined, and that there is a set of cultural, social and political resources upon which future generations may draw in their incessant attempts to realize a just cosmopolitan order. (Reference Ypi2010: 123)
The main problem then of Ypi’s interpretation is that it gives a collectivist moral purpose to the natural teleology of progress, when Kant’s theory should rather be interpreted as a natural teleology that gives way to the possibility of morality in the free individual.Footnote 19 In this sense, TPP invokes the idea of the great ‘providence’ of nature whereby war will even disperse humanity across the globe until the point where it makes peace a necessity, i.e. until it leaves no other practicable option except the moral one, which then has to be achieved cooperatively. Finally, Seán Molloy’s Kant’s International Relations (Reference Molloy2017) offers another substantivist account. Despite its failures,Footnote 20 he clearly recognizes the way in which Kant’s teleological views, particularly in the CJ, are of central importance to understanding the later political writings. Given the narrower focus on international relations theory, what Kant would cover under the ‘right of nations’ in DR and in TPP, it actually helps to emphasize the teleological elements of Kant’s view of perpetual peace as the highest political good:
The political theoretical significance of the Critique of the Power of Judgment is that it is (at least in part) an attempt to argue the possibility of there being a positive telos for the human race: that a reformed human species may be thought of as the end of nature. Kant’s sacrifice of knowledge enables not only faith in God and humanity but also hope in the future. (Molloy Reference Molloy2017: 51)
This overstates part of the project. Kant did not sacrifice his concern for what we can know, even in the realm of aesthetics and teleology,Footnote 21 and neither did he argue for the possibility of these moral-anthropological claims. Rather, Kant consistently argues that we are rationally permitted to take these as real,Footnote 22 even if we must treat them as merely possible from the reflective standpoint of theoretical reason.
While Molloy does not analyse the notion of perpetual peace and the Rechtslehre using the notion of highest good, he also clearly recognizes the key difference between morality and law: ‘The pure moral philosophy is not identical to the philosophy of right, and in this margin of difference Kant develops an important distinction between external and internal duties’ (Molloy Reference Molloy2017: 84). Given this wide gulf, it is thus possible to see that perpetual peace, while correctly considered as the highest political good, could not be a complete good, given the vital importance that motivation plays in Kant’s moral thought, even if it is ultimately optional from the standpoint of the realizability of perpetual peace.
Finally, Molloy highlights how Kant’s theory of perpetual peace in some sense does require a kind of faith that such a state will be achieved through providential workings, rather than our own doing:
It is for this reason that Kant advocates that providence and not nature is ultimately the foundation of perpetual peace … with the ultimate effect being the supersession of the political by the moral as a consequence of the effects of both natural and rational processes playing themselves out according to their own internal logic. (Reference Molloy2017: 161)
Thus, Molloy presents a straightforward reading of Kant as giving a metaphysical view of humanity’s state in the world and what good it should strive towards. The main flaw with Molloy’s reading is that it perhaps goes too far to read in particular theological commitments that Kant simply may not have had. Even if we take it that ‘Kant’s efforts are perhaps better understood as an attempt to translate previous concepts into forms compatible with his philosophy’ (p. 162), Kant is still much more willing to treat purposes in nature as real, and so taking it as true that nature is ‘providentially’ impelling us towards a particular state of social organization can be justified even without actually ascribing a ‘final end’ to it.
4. Vindicating providence
The previously discussed interpretations all attempt to both understand Kant’s arguments in TPP and to align them with other aspects of Kant’s writings, either with his moral philosophy or with his theoretical philosophy (insofar as Kant’s moral philosophy generally is related to the metaphysics of transcendental idealism and insofar as TPP offers particular difficulties relating to Kant’s views on history and teleology). Every interpretation discussed so far emphasizes some aspect of Kant’s system at the expense of another, either highlighting Kant’s formal treatment of moral principles or offering a problematic view of Kant’s teleological views.
By contrast, I will look at his notion of teleology in terms of an interlocking system of free and natural laws. While counterintuitive, this does present a way in which to avoid some of the problems that Baiasu (Reference Baiasu, Valentin and Shunzo2013) points to in identifying the two notions of the highest good (the supreme and the complete good) too superficially, and it allows for a characterization of perpetual peace as a notion of a complete good as well as the supreme good, albeit in an attenuated form.Footnote 23
Contra Baiasu (Reference Baiasu, Valentin and Shunzo2013), and the formalist view as a whole, I believe perpetual peace includes aspects of both the supreme and complete good, even without assimilating the latter into the notion of the highest ‘ethical’ good. I will cite here two textual reasons. The first relates to the preliminary articles of perpetual peace. Without certain material assurances barring certain motives for waging war, or certain ways of conducting hostile yet covert activity against other states, it would hardly seem that one has entered a condition of peace, but rather only a truce, a cease-fire in a perpetual state of war. Thus, it seems that perpetual peace requires certain conditions to be met that Kant himself admits can only be progressively fulfilled.
The second reason is tied to the first two definitive articles, that ‘the civil constitution of all states shall be republican’ and ‘the law of nations shall be founded on a federation of free states’. It seems that people have to exit the state of nature ‘locally’, and then states would have to enter into a civil condition between themselves once relations and interactions require (and permit) it. This is covered by the establishment of a rightful juridical condition. For example, suppose a small group of people tried to regulate their coexistence in such a way that hostile relations would cease. This could not be done by the strongest party, coercing the submission of everyone else to its own private will. Such a condition might be the cessation of the state of nature and the establishment of ‘a’ civil condition, but it fails as the establishment of a ‘rightful condition’. While Kant accepts that an unjust condition can be reformed towards a rightful one, the same cannot happen in the international situation. We cannot hope to establish a civil condition between states by compelling the submission of the majority of states to one state and then reforming towards a juridical condition; we can only establish a rightful condition based on voluntary organization at its foundation. Then, once established, there is nothing more to look for in the notion of perpetual peace by way of completing it.
Yet there still remains a problem with accounting for the specific purpose of the preliminary articles. Keeping the empirical part of the preliminary articles in mind, we can see that Kant is at least in part mindful of certain conditions working in tandem with the formal/legal framework that is supposed to constitute the condition of perpetual peace. Even looking to Kant’s comments on the preliminary articles, he comments that while all six of the preliminary articles are prohibitions (leges prohibtivae), only articles 1, 5, and 6 are strict, whereas 2, 3, and 4 take into consideration the circumstances under which they are applied, and thus have latitude with respect to their being undertaken for the sake of the final end of perpetual peace, all of which is characteristic of Kant’s discussion of duties of virtue. If Kant thus includes at least some prescriptions that are only to be implemented gradually over time, it is arguable that perpetual peace as the highest political good mirrors the highest ethical good, in that it includes a material component in addition to the formal framework of right. Preliminary article 4 is explicitly economic, and it is possible that there are further ones that a more developed political economy might specify.Footnote 24
Thus, if there are any material principles that are active in contributing to the establishment of perpetual peace, they would have to be usefully concrete (while also preventing counterproductive outcomes to otherwise permissible actions). Where the definitive articles give the form of a cosmopolitan condition of right, the preliminary articles prohibit those actions that could only be undertaken with the end of perpetuating war, and prohibiting these would advance states materially in terms of increasing the chance of realizing a peaceful condition.
Specifying the concrete matter needed to institute perpetual peace would be a very different exercise from formulating a system of international peace in outline. To follow Pinheiro-Walla (Reference Walla2017), some of the ‘material lack’ can be filled out by taking into account empirically contingent limitations and restrictions on how, e.g. a universal juridical condition would be established worldwide. Thus, we can look to the moments where Kant is applying a ‘methodologically realist’ position in response to some issues of implementation. In this sense, as Ripstein (Reference Ripstein2016: 190 ff.) points out, Kant also still retains elements of ius in bello insofar as some of the prohibitions in the preliminary articles are supposed to prevent undermining any possible future peace.
Additionally, we need to keep in mind that humans are driven by natural processes. To take Kant’s main culprit, unsocial sociability (Idea [1784], 8: 20–2) can be counted on to explain some behaviour, whether for seemingly certain good or ill. How this could be ‘used’ as a technical tool for optimising the institution of legal norms is unclear. Even if policies could be formulated that did take our unsocial sociability into account in order to produce peace as the desired outcome, we would still have to hope that nature is sufficiently attuned to our political and ethical choices that peace can ultimately be achieved. In this sense, however, we are treading more deeply into the metaphysics of morals that Kant laid out over the span of the critical period, from the GMM perhaps even beyond to the CF and the Anthropology.
In conclusion, I believe Kant’s view of perpetual peace as the highest good is that it is the highest political good as the final end of justice, that it can be instituted by beings with mere instrumental reason, but only perfected through the work of moral politicians, and that it is ordered towards the realization of the highest good as the final end of the world. The highest political good also includes notions of completeness to the degree that the ends limited or prohibited in the preliminary articles show us to what extent we are actually secure in establishing the cosmopolitan condition laid out in the definitive articles.
The last part is perhaps the most striking for its metaphysical ambition, but given the sequence that I have laid out, it follows straightforwardly from the teleology of the CJ. Particularly in §§82–84 regarding the ‘ultimate’ and ‘final’ end of nature (or the world), Kant sees nature bringing about a Culture of Skill and a Culture of Discipline in humanity for the sake of preparing the way for a being that can determine its will in accordance with the laws of freedom.
5. Objections
Turning now to objections to these considerations, while some of the preliminary articles do present features comparable to duties of virtue in latitude and application with regard to a final end, the dissimilarities are still pressing and need to be addressed.
First, does this account really clarify what Kant means by calling perpetual peace the final end of the Doctrine of Right? Is it a mistake on the part of Kant to call it an end, or are there other ways of interpreting perpetual peace as an end? One possibility here is that Kant is invoking a distinction from §§82–84 in CJ between ultimate and final end. Unfortunately, letzter Zweck in the Doctrine of Right is translated as ‘final end’, rather than the term used in the Guyer/Matthews translation of CJ, which puts letzter Zweck as ‘ultimate end’. Thus, if we read perpetual peace as the ultimate end of the Doctrine of Right, understood as a systematic whole of mutually interacting laws, then we can also read perpetual peace as a complete good, since it contains the unconditioned condition of any international state of affairs that could be considered just, while also treating the condition itself as the highest possible good.
Tied to the progress question, if nature only really produces the outward conditions and our own moral intentions are radically opaque to ourselves, how can we have any assurance that establishing external legality could give way to internal morality? To some extent, this is an acceptable, unresolvable problem for a Kantian theory.Footnote 25 Since we should take the move to the ethical commonwealth to be a real transition, there may be an in-principle problem in distinguishing a state and society that is bound together by mere legality from one animated by true morality. Furthermore, we should be able to have practical assurance that, by acting ‘as if’ this end is realizable, we are in fact bringing about this goal in the phenomenal world (even if not in a complete sense).
Secondly, are the features of the preliminary articles really reminiscent of the duties of virtue? Can’t they be explained through Kant’s invocation of the notion of a permissive law, which then would reintegrate that into the formal account of the Doctrine of Right? According to Hruschka (Reference Hruschka2004), Kant revised the notion of permissive law in the MM, where those features of the permissive laws that bring it closer to duties of virtue disappear. Now, there are two possibilities given this revision: either they are not permissive laws, but somehow otherwise still have these features of latitude in their application, or they are permissive laws, which then have to be reinterpreted as not having the form of latitude that Kant ascribes to them in TPP. Only the former would be consistent with the reading proposed here and would be required insofar as those principles are supposed to contribute to perpetual peace as a complete whole.
Further, if nature is indeed always guiding us and producing a system that institutes legality and prepares us for morality, what work is there left for us to do? Even if we do not necessarily need a moral motive to accomplish this, it seems that the work of the legislator is superfluous if the state that nature will produce for humans is going to be one that accomplishes all of the goals of peaceable sociality.Footnote 26 One possible response may be to note that this is the only way for humans to enter, through freedom, into a rightful condition in the international setting. Assuming that states could be forced to enter into a rightful condition between them,Footnote 27 and accepting Kant’s arguments that the best we can hope to be achieved is a looser voluntary federation,Footnote 28 we could consider that nature is the only thing that is powerful enough to establish perpetual peace. However, nature does not operate by laws of freedom and so would still require humans, however late in the process, to make an affirmative decision in favour of establishing peace.
Finally, does this account not fall prey to a variation of an objection from Baiasu (Reference Baiasu, Valentin and Shunzo2013)? This account would not require that people adopt moral ends in order to institute perpetual peace, but it would require more than simply establishing a juridical condition obtaining between states, since states would have to adopt a number of prescriptions that carry with them the particular end of promoting the cessation of violence, even though such actions or institutions, like incurring debt, are not strictly prohibited. Here, I would say that this can be mitigated by considering that these prescriptions are inserted into the legal framework, taking the whole of the legal-political framework as a system of interacting laws. If we assume that we are right to take the legal framework as also amenable to a teleological description, with perpetual peace as its ultimate end, then a number of further determinations would have to be made with respect to actually institutionalizing a juridical condition. This institutionalization may or may not occur due to morally motivated actions, which is ultimately an empirical-historical matter to be determined in the course of history. In fact, Kant’s gloss on the moral politician, noting that they will ‘make it a duty … to be concerned about how [unpreventable defects in the constitution of a state] can be improved as soon as possible … even at the cost of sacrifices to their self-seeking’ (8: 372) shows that such a figure may be indispensable in critical times where choices could be made to make substantial progress towards peace, even at the cost of one’s self-interest.
6. Conclusion
Kant’s view of nature as a providential guarantor of perpetual peace need not worry us that Kant is making dogmatic metaphysical claims, nor does he opt for explanations of his theory that run counter to the limitations that he himself places on his teleology. Obviously, Kant’s moral theory has enough resources to allow us to speak as if nature were teleologically structured, without this committing us to a real causality of purposes. Indeed, the form of the natural law is intelligible as a type Footnote 29 of the moral law, such that a legal arrangement that underwrites perpetual peace will at least have the correct external form in terms of behaviour.
Nature thus produces in a real sense external behaviour that can be measured against the moral law. The reality of acting according to the principle of evil (cf. Rel, 6: 41–4) can thus always endanger this order and can interrupt the ‘regular’ progress of history. Thus, we should also never be satisfied with applying a conception of progress to historical processes, since we can never really know the inner reality of what is motivating these processes or whether it will be a lasting achievement. In this sense, perpetual peace does offer us a complete good, insofar as a perfected global legal-juridical condition (i.e. ‘perfected’ with respect to the question of perpetual peace) is at least a specifiable goal that can in-principle be achieved. While a full development of these ideas remains beyond the scope of this paper, it can be stated clearly that Kant offers the arguments in TPP within the context of the attitude of practical faith and the kind of hope that is offered as early as CPR, which of course has to involve the participation of human beings in real, natural processes, but which we in some sense cannot have incontrovertible, conclusive evidence for. Kant’s teleological views in CJ thus complement and complete these views, which then find their application in TPP, even if this can only be suggested here.
Finally, to answer the question at the beginning of this paper, ‘what must I do to achieve perpetual peace?’, Kant in some sense already offers an answer in the Guarantee: ‘Seek ye first the kingdom of pure practical reason and its justice, and your end (the blessing of perpetual peace) will come to you of itself’ (8: 378). While the allusion to the Sermon on the Mount may be intended ironically, Kant very much does hold it as a matter of practical faith that if we sincerely commit ourselves to fulfilling our duty, the proposed end will be realized. As a matter of practical faith, then, we can be assured that the goal not only will be realized, but that it will actually be better realized through a serious commitment to legal principles than through other means.
Acknowledgements
I want to acknowledge here my indebtedness to Sorin Baiasu, who has seen this material in various stages during my time as a doctoral candidate and after, Garrath Williams and Andrea Esser, who read this paper and contributed many helpful comments, as well as audiences at the ECPR Kantian Standing Group meeting in 2018 and the Amsterdam Kant Conference in 2024 for their questions and input. Finally, I want to acknowledge the anonymous reviewers and editors who helped sharpen the expression and argumentation in this paper.
