I raise a problem about the possibility of metaphysics originally raised by Kant: what explains the fact that the terms in our metaphysical theories (e.g. “property”) refer to entities and structures (e.g. properties) in the world? I distinguish a meta-metaphysical view that can easily answer such questions (“deflationism”) from a meta-metaphysical view for which this explanatory task is more difficult (which I call the “substantive” view of metaphysics). I then canvass responses that the substantive metaphysician can give to this Kantian (...) demand for an explanation of reference in metaphysics. I argue that these responses are either inadequate, or depend, implicitly or explicitly, on the idea of “joint carving”: carving at the joints is part of the explanation of reference-facts quite generally and our metaphysical terms in particular refer because they carve at the joints. I examine Ted Sider’s recent work on joint carving and structure and argue that it cannot fill the explanatory gap. I conclude that this is reason ceterus paribus to reject the substantive view of metaphysics. Kant’s critique, far from being obsolete, applies to the most cutting-edge of contemporary meta-metaphysical views. (shrink)

In this paper, I examine Kant's famous objection to the ontological argument: existence is not a determination. Previous commentators have not adequately explained what this claim means, how it undermines the ontological argument, or how Kant argues for it. I argue that the claim that existence is not a determination means that it is not possible for there to be non-existent objects; necessarily, there are only existent objects. I argue further that Kant's target is not merely ontological arguments as such (...) but the larger ‘ontotheist’ metaphysics they presuppose: the view that God necessarily exists in virtue of his essence being contained in, or logically entailed by, his essence. I show that the ontotheist explanation of divine necessity requires the assumption that existence is a determination, and I show that Descartes and Leibniz are implicitly committed to this in their published versions of the ontological argument. I consider the philosophical motivations for the claim that existence is a determination and then I examine Kant's arguments in the Critique of Pure Reason against it. (shrink)

While scholars have extensively discussed Kant’s treatment of the Principle of Sufficient Ground in the Antinomies chapter of the Critique of Pure Reason, and, more recently, his relation to German rationalist debates about it, relatively little has been said about the exact notion of ground that figures in the PSG. My aim in this chapter is to explain Kant’s discussion of ground in the lectures and to relate it, where appropriate, to his published discussions of ground.

There is substantial textual evidence that Kant held the doctrine of double affection: subjects are causally affected both by things in themselves and by appearances. However, Kant commentators have been loath to attribute this view to him, for the doctrine of double affection is widely thought to face insuperable problems. I begin by explaining what I take to be the most serious problem faced by the doctrine of double affection: appearances cannot cause the very experience in virtue of which they (...) have their empirical properties. My solution consists in distinguishing the sense of ‘experience’ in which empirical objects cause experience from the sense of ‘experience’ in which experience determines empirical objects. I call the latter “universal experience”. I develop my conception of universal experience, and then I explain how it solves the problem of double affection. I conclude by addressing several objections. (shrink)

In this essay I offer a partial rehabilitation of Cohen’s Kant interpretation. In particular, I will focus on the center of Cohen’s interpretation in KTE, reflected in the title itself: his interpretation of Kant’s concept of experience. “Kant hat einen neuen Begriff der Erfahrung entdeckt,”7 Cohen writes at the opening of the first edition of KTE (henceforth, KTE1), and while the exact nature of that new concept of experience is hard to pin down in the 1871 edition, he states it (...) succinctly in the second edition (henceforth KTE2): experience is Newtonian mathematical natural science.8 While this equation of experience with mathematical natural science has few contemporary defenders, I believe it is substantially correct, with one important qualification. Kant uses the term Erfahrung in a number of different senses in the Kritik der reinen Vernunft (henceforth, KrV). I will argue that a central, and neglected, sense of that key technical term aligns with Cohen’s reading; what Kant sometimes refers to as ‘universal experience’ (sometimes, simply ‘experience’) is, in broad outlines, correctly interpreted by Cohen as mathematical natural science. (shrink)

In the section “Validity and Existence in Logik, Book III,” I explain Lotze’s famous distinction between existence and validity in Book III of Logik. In the following section, “Lotze’s Platonism,” I put this famous distinction in the context of Lotze’s attempt to distinguish his own position from hypostatic Platonism and consider one way of drawing the distinction: the hypostatic Platonist accepts that there are propositions, whereas Lotze rejects this. In the section “Two Perspectives on Frege’s Platonism,” I argue that this (...) is an unsatisfactory way of reading Lotze’s Platonism and that the Ricketts-Reck reading of Frege is in fact the correct way of thinking about Lotze’s Platonism. (shrink)

According to the ‘One Object’ reading of Kant's transcendental idealism, the distinction between the appearance and the thing in itself is not a distinction between two objects, but between two ways of considering one and the same object. On the ‘Metaphysical’ version of the One Object reading, it is a distinction between two kinds of properties possessed by one and the same object. Consequently, the Metaphysical One Object view holds that a given appearance, an empirical object, is numerically identical to (...) the thing in itself that appears as that object. I raise various indiscernibility arguments against that view; because an appearance has different spatiotemporal and modal properties than a thing in itself, no appearance can be identical to a thing in itself. I point out that these arguments are similar to arguments against Monism, the view that material objects are numerically identical to the matter of which they are made. I outline some strategies Monists have developed to respond to these indiscernibility arguments and then develop parallel responses on behalf of the Metaphysical One Object view. However, I then raise another indiscernibility argument, to which, I argue, the Metaphysical One Object view cannot respond, even using the resources I have developed thus far. I develop a modified version of the Metaphysical One Object view that can respond to this new indiscernibility argument, but, I argue, this modified version of the One Object view is only a terminological variant of the Two Object view. When the Metaphysical One Object view is fully thought through it becomes the Two Object view. I conclude that Kantian appearances are not numerically identical to the things in themselves that appear to us. (shrink)

In a recent paper, Desmond Hogan aims to explain how Kant could have consistently held that noumenal affection is not only compatible with noumenal ignorance but also with the claim that experience requires causal affection of human cognitive agents by things in themselves. Hogan's argument includes the premise that human cognitive agents have empirical knowledge of one another's actions. Hogan's argument fails because the premise that we have empirical knowledge of one another's actions is ambiguous. On one reading, the argument (...) is valid but its conclusion trivial. On the other, it is unsound on Kant's own view.Export citation. (shrink)

In the Transcendental Ideal Kant discusses the principle of complete determination: for every object and every predicate A, the object is either determinately A or not-A. He claims this principle is synthetic, but it appears to follow from the principle of excluded middle, which is analytic. He also makes a puzzling claim in support of its syntheticity: that it represents individual objects as deriving their possibility from the whole of possibility. This raises a puzzle about why Kant regarded it as (...) synthetic, and what his explanatory claim means. I argue that the principle of complete determination does not follow from the principle of excluded middle because the externally negated or ?negative? judgement ?Not (S is P)? does not entail the internally negated or ?infinite? judgement ?S is not-P.? Kant's puzzling explanatory claim means that empirical objects are determined by the content of the totality of experience. This entails that empirical objects are completely determinate if and only if the totality of experience has a completely determinate content. I argue that it is not a priori whether experience has such a completely determinate content and thus not analytic that objects obey the principle of complete determination. (shrink)

In this paper I address a structurally similar tension between phenomenalism and realism about matter in Leibniz and Kant. In both philosophers, some texts suggest a starkly phenomenalist view of the ontological status of matter, while other texts suggest a more robust realism. In the first part of the paper I address a recent paper by Don Rutherford that argues that Leibniz is more of a realist than previous commentators have allowed. I argue that Rutherford fails to show that Leibniz (...) is any less an idealist than his main target, Robert Merrihew Adams, does. I distinguish various kinds of idealism about bodies that Leibniz might have held, and attempt to determine which package of views represents his considered view. In the second part of the paper I situate Kant’s idealism within the same coordinates. I argue that, abstracting from deep differences in their metaphysics and epistemology, Kant and Leibniz have structurally very similar views on the ontological status of matter and bodies. I conclude that the key to understanding the realist strand in their ontology of matter is understanding the way in which, for both thinkers, the forces in bodies are appearances of forces of more fundamental entities, either monads or things in themselves. (shrink)

This essay is an attempt to explain Kantian transcendental idealism to contemporary metaphysicians and make clear its relevance to contemporary debates in what is now called ‘meta-metaphysics.’ It is not primarily an exegetical essay, but an attempt to translate some Kantian ideas into a contemporary idiom.

One of Bolzano’s objections to Kant’s way of drawing the analytic-synthetic distinction is that it only applies to judgments within a narrow range of syntactic forms, namely, universal affirmative judgments. According to Bolzano, Kant cannot account for judgments of other syntactic forms that, intuitively, are analytic. A recent paper by Ian Proops also attributes to Kant the view that analytic judgments beyond a limited range of syntactic forms are impossible. I argue that, correctly understood, Kant’s conception of analyticity allows for (...) analytic judgments of a wider range of syntactic forms. (shrink)

In §12 of his 1837 magnum opus, the Wissenschaftslehre, Bolzano remarks that “In the new logic textbooks one reads almost constantly that ‘in logic one must consider not the material of thought but the mere form of thought, for which reason logic deserves the title of a purely formal science’” (WL §12, 46).1 The sentence Bolzano quotes is his own summary of others’ philosophical views; he goes on to cite Jakob, Hoffbauer, Metz, and Krug as examples of thinkers who held (...) that logic abstracts from the matter of thought and considers only its form. Although Bolzano does not mention Kant by name here, Kant does of course hold that “pure general logic”, what Bolzano would consider logic in the traditional sense (the theory of propositions, representations, inferences, etc.), is formal. As Kant remarks in the Introduction to the 2nd edition of Kritik der reinen Vernunft , (pure general) logic is “justified in abstracting – is indeed obliged to abstract – from all objects of cognition and all of their differences; and in logic, therefore, the understanding has to do with nothing further than itself and its own form” (KrV, Bix).2. (shrink)