Because my time and competence are limited, I shall avoid exegetical discussion of Kant and restrict myself to discussion of some of the apparent implications of the views attributed to Kant by van Ackeren and Sticker (AS) in their insightful and suggestive article.

Where Rawls’s The Law of Peoples addresses war and the use of force then his position has often been identified closely with Walzer’s restatement of just war theory, as both positions appear to take nation-states, and the conflicts between them, to be the bedrock of the international system. On the other hand, Kant’s notion of a peaceful federation of states presents us with the notion of a world without war and where the international system is transformed. This article argues that Rawls’s account of the use of force is better understood if we read it with an eye to its resonances with Kant rather than with Walzer. Doing so rewards us with a clearer understanding of central aspects of Rawls’s account of just war and vision of international politics.

Wittgenstein’s private language argument claims that language and meaning generally are public. It also contends with our appreciation of artworks and reveals the deep connection in our minds between originality and the temptation to think of original meaning as private. This problematic connection of ideas is found in Kant’s theory of fine art. For Kant conceives of the capacity of artistic genius for imaginatively envisioning original content as prior to and independent of finding the artistic means of communicating this content to others. This raises the question of whether we can conceive of art as both original and meaningful without succumbing to privacy.

Chapter 4 of Dennis Schulting’s book Kant’s Radical Subjectivism targets those commentators who take there to be a gap in the transcendental deduction of the categories, arguing instead that there is no gap between the necessary application of the categories and their exemplification in the object of experience. In these comments on the chapter, I suggest a minimal sense in which the fact that there is a gap is non-negotiable. The interesting question is not whether there is a gap which needs to be bridged, but how and why Kant makes the step from subjectivity to objectivity.

Matter’s real essence is a ground for certain features of phenomena. Things in themselves are likewise a ground for certain features of phenomena. How do these claims relate? The former is a causal essentialism about physics, Stang argues; and the features so grounded are phenomenally nomically necessary. The latter involves a distinctive ontology of things in themselves, I argue; but the features so grounded are not noumenally nomically necessary. Stang’s version of Kant’s modal metaphysics is admirable, but does not go far enough. Kant’s causal essentialism involves the essences of fundamental properties, as well as of matter. And things in themselves are grounds, because they are substances, the ‘substrate’ of phenomena.

I argue, contrary to Dennis Schulting in Kant’s Radical Subjectivism, that the main reasoning of Kant’s transcendental deduction of the categories is progressive, not regressive. Schulting is right, however, to emphasize that the deduction takes the object cognized to be constituted in an idealism-entailing way. But his reasoning has gaps and bypasses Kant’s most explicit deduction argument, independent of the Transcendental Aesthetic, for idealism. Finally, Schulting’s claim that Kantian discursivity itself requires idealism overlooks the fact that Kantian general judgements can be true in a domain of objects without being specifically of or about any particular ones of those objects.

Logicism is Stang’s name for the Leibnizian doctrine that all necessary truths are derivable from identities and definitions. Stang shows that the early Kant opposed this doctrine because he thought the proposition God exists was a counterexample to it; I raise some non-theological counterexamples as well. Formal necessity is the necessity that attaches to a proposition when its truth is grounded in our categories and forms of intuition. Stang treats it as one of several sui generis kinds of necessity in Kant, all of them falling short of logical or metaphysical necessity. I raise several questions for Stang’s account, including the following: Can our having the forms we do really explain the necessity of geometry? Is our possession of those forms self-grounding in an objectionable way? How can our forms ground general truths without grounding particular instances of them?

In this paper I discuss four ways in which Schulting’s phenomenalist interpretation of Kant faces the challenge of accounting for the possibility of objective cognition. First, I ask whether objective cognition requires the understanding to be a faculty of absolute, not merely relative spontaneity. Second, is objectivity compatible with thinking of the transcendental ‘I’ as an indexical? Third, does objectivity require that the objects have being independently of the understanding? Finally, is it a threat to objectivity if objects can be given to me in sensibility without standing under the categories?

In this critical review, I focus on two things. First, I respond to Stang’s interpretation of Descartes, according to which Descartes’ endorsement of his ontological argument commits him to possibilism, the doctrine that there are, or at least could be, non-existent individuals. My response consists in presenting a version of Descartes’ argument the acceptance of which does not require the acceptance of possibilism. The second thing I focus on is Stang’s claim that Kant distinguishes several kinds of real possibility. I raise worries about Stang’s formulations of various doctrines of real possibility, and I preliminarily explore how real essence and ground are connected with the various kinds of real necessity Stang’s Kant recognizes.