Kant’s political sovereign carries a heavy burden of responsibility.^{Footnote 104} They are bound to make political judgments, but neither a priori principles, nor regents, judges, legal institutions nor positive law provide certain guidance. This is the limit of law in Kant’s political philosophy: Law can never fully subordinate political judgment. In this limit, Kant recognises that the force of empirical political circumstances on us finite beings mandates that judgment is exercised at every step in politics. However, he also holds that this judgment has a moral quality and a moral force. Prudent judgment is grounded not in instrumental reasoning, but in the obligation to maintain the state. Kant morally vindicates the role of prudence at the heart of his politics; exercised in accordance with rightful principle, prudence is not amoral or immoral, but is, to the contrary, deeply moral. This is what he means when he claims that a moral politician is ‘one who takes the principles of political prudence in such a way that they can coexist with morals’.^{Footnote 105} Rightful political judgment requires the sovereign as a moral politician to exercise political judgment to navigate the twin obligations to rule through rightful law-making and to maintain the necessity of the state. To emphasise the role of political judgment in Kant’s politics is not to dismiss the importance of moral judgment. It is rather to argue that there is a form of moral judgment distinctive to politics, and that the responsibility for this judgment falls on the sovereign above all.^{Footnote 106}

To conclude this paper, I want to set out where my arguments leave me in relation to Kantian legalism and to the literature on Kant’s political philosophy more broadly. The active, political, prudential and judging Kantian sovereign I have argued for is in stark contrast to any legalist reading of the concept. As an interpretation of the ambiguity inherent in the notion of sovereignty, the political conception emphasises that, for Kant, establishing, maintaining and improving a rightful constitution in the world is not a legal project but a political one.^{Footnote 107}The Doctrine of Right is the key text for understanding how he understands right and law and, in the central concept of sovereignty, Kant grounds law on the political judgment of the sovereign. Political judgment is thus central to The Doctrine of Right, not the marginal concern it often appears to be in Kantian legalism.

As well as this difference with Kantian legalism, my view also contrasts with approaches to political judgment in Kant which follow Hannah Arendt in drawing on material from Kant’s Critique of the Power of Judgment, and as well as from other of Kant’s political, anthological, or historical writings.^{Footnote 108} A full picture of the role of political judgment in Kant’s political philosophy might well require these kinds of accounts. But my purpose here, and my challenge against the Kantian legalist, is to show that the principles derived in The Doctrine of Right itself, are principles of political judgment, not only of legal systems. It is not only in his historical, anthropological, and pedagogical writings, and well as other texts on politics, that judgment is key for Kant. Though these writings may take up the question of the refinement of political judgment, it is in The Doctrine of Right that the central importance of political judgment is established. By contrast with Arendt who declared Kant never wrote a political philosophy – a point Ronald Beiner refined by saying that, since Kant supposedly sees no place for prudence, he has no account of political judgment^{Footnote 109} – for Kant, as I read him, political judgment determines the relationship of law and politics. My claim thus does not amount to the well-established understanding that Kant thought that moral principles, such as those found in The Doctrine of Right, require supplementation by judgment, something that Kantian legalists are as clear about as any other group of interpreters.^{Footnote 110} Rather my claim is that the moral principles of The Doctrine of Right should be understood as apt for judgment. That is, as principles of political judgment.

Kant’s complex ideal of the ‘state in idea’ or Rechtsstaat arises from two obligations, to rule rightfully through law and to maintain the state, which can become contradictory under certain empirical circumstances. Whilst a legalist reading would attempt to resolve such a possible contradiction through the precise delineation of principles in philosophy, I have argued that Kant held that for this task the sovereign’s practical political judgment is central. Thus, contrary to Kantian legalism, politics is not subordinated to law, rather law depends on political judgment. The task of politics is not only to apply law in particular circumstances; the task of politics judge what is necessary to secure the conditions in which a legal system, grounded on a priori principles, could exist.

As Kant puts it in his reply to criticism from Benjamin Constant, politics is a problem, the problem of how to arrange society in accordance with freedom and equality.^{Footnote 111} It is a problem finite human beings face, perhaps perpetually, and that requires judgment, not only law and principles, to manage successfully. It is this thought of Kant’s, though not necessarily ‘Kantian’ thought, that I have tried to understand in this paper, a task which legalistic readings have not undertaken. I don’t claim to have decisively refuted such readings, only suggested that another kind of interpretation is possible, one embraces the active ambiguity in Kant’s conception of sovereignty as being the result of the practical and political perspective from which he wrote and judged.