Kant: Modality

Kant’s postulate of possibility states that possible is whatever agrees with the formal conditions of experience. As has often been noted, this is a definition of real possibility. However, little attention has been paid to the relation of Kantian real possibility to the German philosophical tradition before him. I discuss three kinds of possibility present in this tradition – internal, external, and (Crusian) real possibility – and argue that Kant endorses internal and external possibility. Furthermore, I show, specifically with respect (...) to the concept of state (Zustand), that the three traditional conceptions are reminiscent of three conceptions of real possibility that Kant implicitly distinguishes. Lastly, I argue that, according to Kant, we need experience to prove real possibility (at least as regards the three conceptions of the real possibility of states) because otherwise we could not know whether the formal conditions of experience obtain. (shrink)

This paper investigates Kant’s account of “real essence” and of a thing’s “nature”. Notwithstanding their wide negligence in the literature, these concepts belong to the central ones of Kant’s metaphysics. I argue that, on the one hand, Kant is in continuity with the Aristotelian-Scholastic tradition of essence. But, on the other hand, he also follows Locke in distinguishing between “logical” and “real” essence. Contrary to recent attempts of aligning real essence with contemporary approaches to essence, I will defend the thesis (...) that Kant equates real essence and (formal) nature, and that real essence has a causal, but no constitutive role. I shall also respond to potential objections and discuss some developments of Kant’s views. (shrink)

This paper proposes a novel reading of Kant’s account of the dependence of possibility on God in the pre-Critical Beweisgrund. I argue that Kant has a theistic-potentialist conception of the way God grounds possibility, according to which God grounds possibility by his understanding and will. The reason is that Kant accepts what I call the Principle of Possible Existence: If something is possible, then it is possible that it exists. Furthermore, I explore the connection between causal powers and possibility, the (...) influence of Crusius on Kant, and the significance of the distinction between internal and external possibility. (shrink)

This essay reassesses the relation between Kant and Kripke on the relation between necessity and the a priori. Kripke famously argues against what he takes to be the traditional view that a statement is necessary only if it is a priori, where, very roughly, what it means for a statement to be necessary is that it is true and could not have been false and what it means for a statement to be a priori is that it is knowable independently (...) of experience. Call such a view the Entailment Thesis. Along with many Kant scholars, Kripke thinks that Kant endorses the Entailment Thesis. Thus Kripke and many others take his arguments against the Entailment Thesis to tell against Kant and to mark an important point of disagreement with him. I will argue that this is a mistake. Kant does not endorse the Entailment Thesis that Kripke and many others attribute to him. He does endorse two quite different theses concerning the relation between necessity and the a priori, as he conceives them. One is a matter of definition and the other is a very substantial philosophical thesis indeed—to establish it is the aim of the entire Critique of Pure Reason. But Kripke’s arguments against the Entailment Thesis tell against neither of Kant’s theses, as they involve crucially different conceptions of necessity and the a priori. This superficial lack of disagreement masks deep disagreements, but these result from divergent views regarding matters such as realism, modal epistemology, and philosophical methodology; views which Kant does a lot, and Kripke very little, to argue for. (shrink)

This chapter analyzes several key themes in Kant’s views about modality. We begin with the pre-critical Only Possible Argument in Support of a Demonstration of the Existence of God, in which Kant distinguishes between formal and material elements of possibility, claims that all possibility requires an actual ground, and argues for the existence of a single necessary being. We then briefly consider how Kant’s views change in his mature period, especially concerning the role of form and thought in defining modality. (...) Kant’s mature views, however, present two difficult interpretive puzzles. The first puzzle concerns whether Kant has a generally reductive view of modality. While Kant’s views on logical modality, the role of actuality in grounding possibility, and the relation of modality to cognition all suggest reduction, we argue that the categorial status of modal concepts and the difficulty in even identifying amodal grounds for modal facts all suggest a non-reductive view. The second puzzle concerns whether Kant accepts modal facts or properties at the noumenal level. While Kant’s appeal to noumenal necessary connections, the contingency of noumenal willing, and the idea of a necessary noumenal being suggest that he endorses noumenal modality, his claims that modal concepts express only relations to the faculty of cognition and his claim that modal concepts arise from our distinctive psychological structures, we argue, suggest that he rejects noumenal modality. We conclude by considering potential solutions to these puzzles. (shrink)

In his lectures on Logic and Metaphysics, Kant distinguishes between logical and real essences. While the former is related to concepts and is knowable, the latter is related to things and is unknowable. In this paper, I argue that the unknowability is explained by the modal characteristic of real essences as a necessitating ground on which a priori knowledge is impossible. I also show how this claim is related to the unknowable necessity of particular laws of nature. Since laws of (...) nature are conceived as grounded in real essences, the unknowability of the latter is equivalent to Kant's other claim that there can be no knowledge of the necessity of particular laws of nature. Necessity can only be known a priori, and therefore, the necessity of particular laws is only assumed and conceived as grounded in something unknowable, a real essence. This conclusion will allow me to attribute to Kant a position I label as “regulative essentialism”, meaning that real essences have an indispensable role in accordance with the rational interest to explain nature as a system of laws and natural kinds, combined with an epistemic humility about the correspondence of our empirical concepts to real essences. (shrink)

This essay considers Kant’s theory of modality in light of a debate in contemporary modal metaphysics and modal logic concerning the Barcan formulas. The comparison provides a new and fruitful perspective on Kant’s complex and sometimes confusing claims about possibility and necessity. Two central Kantian principles provide the starting point for the comparison: that the possible must be grounded in the actual and that existence is not a real predicate. Both are shown to be intimately connected to the Barcan formulas, (...) and Kant’s views on what he distinguishes as three different kinds of modality are then considered in light of this connection. (shrink)

The thesis that existence is radically different from the determinacy of an actually existing thing –Kant considers this thesis to be the unsurmountable objection against the cosmological and the ontological argument– is the same thesis that demands a specific explanation of the existence of that actually existing thing. The notion of existence that results from its complete exclusion from the realm of the contents thoroughgoing determined by real predicates requires, thus, precisely because this thoroughness excludes it, a specific reason that (...) explains that in the actually existing thing its own actual existence is in fact united with its own determinacy; that notion of existence, however, cancels at the same time the requirement of a sufficient reason of the existence of what actually exists, and again for the same reason, namely, because since existence is as such excluded from the determinacy of the existing things, it radically differs from the specific realm where determinacy is constituted (that is why existing things are thoroughgoing determined as possible), and, therefore, it invalidates any application to itself of the logical laws that are valid only for the merely possible domain of determinacy. (shrink)

The nature of Kant’s criticism of his pre-Critical ‘possibility proof’ for the existence of God, implicit in the account of the Transcendental Ideal in the Critique of Pure Reason, is still under dispute. Two issues are at stake: the error in the proof and diagnosis of the reason for committing it. I offer a new way to connect these issues. In contrast with accounts that locate the motivation for the error in reason’s interest in an unconditioned causal ground of all (...) contingent existence, I argue that it lies in reason’s interest in another kind of unconditioned ground, collective unity. Unlike the conception of the former, that of the latter directly explains the problematic ontological assumption of the possibility proof, the existence of intelligible objects as the ground of possibility. I argue that such Platonic entities are assumed because they are amenable to the kind of unity prescribed by reason. However, since the interest in collective unity has a legitimate regulative use when applied to the systematic unity of nature, the conception of God entailed by the possibility proof is retained as a regulative idea of reason. (shrink)

According to what Jonathan Bennett calls the Kant–Frege view of existence, Frege gave solid logical foundations to Kant’s claim that existence is not a real predicate. In this article I will challenge Bennett’s claim by arguing that although Kant and Frege agree on what existence is not, they agree neither on what it is nor on the importance and justification of existential propositions. I identify three main differences: first, whereas for Frege existence is a property of a concept, for Kant (...) it is a relational property pertaining between the concept and intuition of an object. Second, whereas for Frege truth about individuals presupposes their existence, for Kant truth is in many cases independent of the existence of objects. Third, whereas Frege binds logic to existence and removes modalities from logic, for Kant existence is a modal category that is emphatically removed from the domain of logic and set in the core of metaphysics. Due to these differences in Kant’s and Frege’s theories of existence, Frege cannot be seen as giving logical clarity to Kant’s view. (shrink)

There are two traditional ways to read Kant's claim that every event necessarily has a cause: the weaker every-event some-cause and the stronger same-cause same-effect causal principles. The focus of the debate about whether and where he subscribes to the SCP has been in the Analogies in the Critique of Pure Reason and in the Metaphysical Foundations of Natural Science. By analysing the arguments and conclusions of both the Analogies and the Postulates as well as the two Latin principles non (...) datur casus and non datur fatum that summarise their results, I will argue for the novel thesis that the SCP is actually demonstrated in the Postulates of the First Critique. (shrink)

In this extended critical discussion of 'Kant's Modal Metaphysics' by Nicholas Stang (OUP 2016), I focus on one central issue from the first chapter of the book: Stang’s account of Kant’s doctrine that existence is not a real predicate. In §2 I outline some background. In §§3-4 I present and then elaborate on Stang’s interpretation of Kant’s view that existence is not a real predicate. For Stang, the question of whether existence is a real predicate amounts to the question: ‘could (...) there be non-actual possibilia?’ (p.35). Kant’s view, according to Stang, is that there could not, and that the very notion of non-actual or ‘mere’ possibilia is incoherent. In §5 I take a close look at Stang’s master argument that Kant’s Leibnizian predecessors are committed to the claim that existence is a real predicate, and thus to mere possibilia. I argue that it involves substantial logical commitments that the Leibnizian could reject. I also suggest that it is danger of proving too much. In §6 I explore two closely related logical commitments that Stang’s reading implicitly imposes on Kant, namely a negative universal free logic and a quantified modal logic that invalidates the Converse Barcan Formula. I suggest that each can seem to involve Kant himself in commitment to mere possibilia. (shrink)

Andrew Chignell and Omri Boehm have recently argued that Kant’s pre-Critical proof for the existence of God entails a Spinozistic conception of God and hence substance monism. The basis for this reading is the assumption common in the literature that God grounds possibilities by exemplifying them. In this article I take issue with this assumption and argue for an alternative Leibnizian reading, according to which possibilities are grounded in essences united in God’s mind (later also described as Platonic ideas intuited (...) by God). I show that this view about the distinction between God’s cognition of essences as the ground of possibility and the actual world is not only explicitly stated by Kant, but is also consistent with his metaphysical picture of teleology in nature and causality during the pre-Critical period. Finally, I suggest that the distinction between the conceptual order of essences embodied in the idea of God and the order of the objects of experience plays a role in the transition into the Critical system, where it is transformed into the distinction between the intelligible and the sensible worlds. (shrink)

In the course of his philosophy, in various contexts, Kant comes to reject three theses about existence: (i) that the thoroughgoing determination of a thing implies its existence, (ii) that existence is a real predicate or determination of a thing, and (iii) that existence is the complement of inner possibility or essence. Kant’s target here is Baumgarten, who advocates these theses as the criterion, classification, and definition of existence. In this article I seek to clarify Kant’s elusive theory of existence (...) through its opposition to Baumgarten. I will show that Kant’s refutation of (i)–(iii) does not stand alone but is grounded on his own definition of existence as (absolute) positing. Thus contrary to common practice, Kant’s negative claims about what existence is not cannot be understood in isolation but must be taken as jointly dependent on Kant’s positive claim of what existence is. I will show that the theses (i)–(iii) fail because they presuppose that existence contributes to the intension or content of a concept, whereas according to Kant existence in fact posits a (non-empty) extension to the concept. (shrink)

One of the better known of the many bons mots of the Sellarsian corpus concerns his definition of philosophy: it is the attempt to understand “how things in the broadest possible sense of the term hang together in the broadest possible sense of the term.” When applied to Sellars’s philosophy in particular, one might be forgiven for doubting the possible success of such an endeavor. Richard Rorty once quipped of Sellars’s followers that they were either “left-wing” or “right-wing,” emphasizing one (...) line of thought in Sellars’s work to the exclusion of the other. The two lines of thought to which Rorty referred were, first, Sellars’s conception of the normativity of all thought and language, famously captured by his evocative phrase “the space of reasons.” Second, and equally important to Sellars, was his “scientia mensura,” the notion ðshared with contemporaries such as Quine that “in the dimension of describing and explaining the world, science is the measure of all things, of what is that it is, and of what is not that it is not” Wilfrid Sellars, “Empiricism and the Philosophy of Mind,” Minnesota Studies in the Philosophy of Science 1 [1956]: 41,303). The left-wing adherents to the normativity thesis included Rorty himself, along with John McDowell and Robert Brandom. Among the right-wing naturalists are such as Ruth Milliken, Jay Rosenberg, and Paul Churchland. Such a disparate group of philosophers suggests irreconcilable differences. Brandom himself reports in the introduction to his newest book, From Empiricism to Expressivism, that, “for a dismayingly long time, I did not really see how all the pieces of [Sellar's] work hung together, even in the broadest possible sense of the term”. (shrink)

Name der Zeitschrift: Kant-Studien Heft: Ahead of print.

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)

I reply to recent criticisms by Uygar Abaci and Peter Yong, among others, of my reading of Kant's pre-Critical of God's existence, and of its fate in the Critical period. Along the way I discuss some implications of this debate for our understanding of Kant's modal metaphysics and modal epistemology generally.

My goal in this paper is to show that Kant’s prohibition on certain kinds of knowledge of things-in-themselves is motivated less by his anti-soporific encounter with Hume than by his new view of the distinction between “real” and “logical” modality, a view that developed out of his reflection on the rationalist tradition in which he was trained. In brief: at some point in the 1770’s, Kant came to hold that a necessary condition on knowing a proposition is that one be (...) able to prove that all the items it refers to are either really possible or really impossible. Most propositions about things-in-themselves, in turns out, cannot meet this condition. I conclude by suggesting that the best interpretation of this modal condition is as a kind of coherentist constraint. (shrink)

I propose to explain Kant’s novel claim, in the Critique of Pure Reason, that all judgments have a formal modality. I begin by distinguishing the modality of a judgment’s form from the modality of its content, and I suggest that the former is peculiar in merely affecting the subject’s understanding of his own act of judging. I then contrast the modal account of such an understanding (in terms of the possibility and actuality of a judgment) with the traditional, non-modal understanding (...) of it (in terms of the giving and withholding of assent). I conclude by suggesting that Kant prefers the former because he conceives of knowledge on Aristotle’s model: as a progress in the mind from capacity to act. (shrink)

In the presentation I will analyse Kant’s conception of modalities and consider its relevance to his critical metaphysics. With his Tables of Judgements and of Categories Kant makes an important division between two kinds of modality, of which the former is only logical and the latter transcendental, i.e., objective. Only judgements that are necessary in both ways are properly metaphysical. This distinction is important for Kant’s distinction between Transcendental Analytic and Transcendental Dialectic, i.e., between acceptable and unacceptable metaphysics. I submit (...) that not only is Kant’s theory of modality useful for properly understanding his arguments in the Dialectic, but that only by distinguishing between the two types of modality can one can make sense of his theory that the ideas of reason are simultaneously inevitable and erroneous. This modal analysis thus offers a new and important point of view to Kant’s metaphysics and its critique. (shrink)

In the first part of the paper I reconstruct Kant’s proof of the existence of a ‘most real being’ while also highlighting the theory of modality that motivates Kant’s departure from Leibniz’s version of the proof. I go on to argue that it is precisely this departure that makes the being that falls out of the pre-critical proof look more like Spinoza’s extended natura naturans than an independent, personal creator-God. In the critical period, Kant seems to think that transcendental idealism (...) allows him to avoid this conclusion, but in the last section of the paper I argue that there is still one important version of the Spinozistic threat that remains. -/- . (shrink)

Kant says that it can be rational to accept propositions on the basis of non-epistemic or broadly practical considerations, even if those propositions include “transcendental ideas” of supersensible objects. He also worries, however, about how such ideas (of freedom, the soul, noumenal grounds, God, the kingdom of ends, and things-in-themselves generally) acquire genuine positive content in the absence of an appropriate connection to intuitional experience. How can we be sure that the ideas are not empty “thought-entities (Gedankendinge)”—that is, speculative fancies (...) that do not and perhaps even cannot have referents in reality? In this paper I argue for an account of the fundamental problem here (i.e. that it is based in a concern about whether or not the objects of such ideas are "really possible" in Kant's technical sense). I then critically evaluate Kant's three proposed solutions to the problem. The third one involves an appeal to the complicated doctrine of "symbolization" that becomes prominent in Kant's later works. -/- . (shrink)

Kant holds that in order to have knowledge of an object, a subject must be able to “prove” that the object is really possible—i.e., prove that there is neither logical inconsistency nor “real repugnance” between its properties. This is (usually) easy to do with respect to empirical objects, but (usually) impossible to do with respect to particular things-in-themselves. In the first section of the paper I argue that an important predecessor of Kant’s account of our ignorance of real possibility can (...) be found in Locke’s Essay Concerning Human Understanding. In the middle sections I discuss the way in which our inability to prove the real possibility of things-in-themselves motivates Kant’s famous prohibition on certain kinds of knowledge-claims about them. In the final section I examine Hegel’s attempts to dissolve this problem of real repugnance and thereby remove an inherited obstacle to speculative knowledge of the supersensible. -/- . (shrink)

Kant's speculative theistic proof rests on a distinction between “logical” and “real” modality that he developed very early in the pre-critical period. The only way to explain facts about real possibility, according to Kant, is to appeal to the properties of a unique, necessary, and “most real” being. Here I reconstruct the proof in its historical context, focusing on the role played by the theory of modality both in motivating the argument (in the pre-critical period) and, ultimately, in undoing it (...) as a source of knowledge of God's existence (in the critical period). Along the way I examine Kant's version of the now-popular “actualist” thesis that facts about what is possible must be explained by facts about what is actual. I conclude by discussing why the critical Kant claims both that there are rational grounds for accepting the conclusion of his theistic proof, and that such acceptance can not count as knowledge. This is important, I argue, because the same considerations ultimately motivate his prohibition on knowledge of things-in-themselves generally. -/- . (shrink)

Ernst Cassirer claimed that Kant's notion of actual object presupposes the notion of truth. Therefore, Kant cannot define truth as the correspondence of a judgement with an actual object. In this paper, I discuss the relations between Kant's notions of truth, object, and actuality. I argue that's notion of actual object does not presuppose the notion of truth. I conclude that Kant can define truth as the correspondence of a judgement with an actual object.

This is the second in a two part series of articles that attempt to clarify the nature and enduring relevance of Kant's concept of a priori knowledge. (For Part I, see below.) In this article I focus mainly on Saul Kripke's critique of Kant, in Naming and Necessity. I argue that Kripke draws attention to a genuine defect in Kant's epistemological framework, but that he used definitions of certain key terms that were quite different from Kant's definitions. When Kripke's definitions (...) are replaced by Kant's definitions, Kripke's account of the status of naming turns out to be a defense of analytic aposteriority as a significant classification of knowledge that Kant neglected. I also introduce here a new way of understanding such epistemological labels, as defining the perspective adopted by the knowing subject in a given situation, rather than an objective characteristic of certain propositions as such. (shrink)