Till Hoeppner

What explains that our concepts possess the representational contents they do, namely, represent whatever they represent? Kant credits Locke’s Essay with first formulating this question about the origin of conceptual content. While the question for the origin of specifically metaphysical concepts, such as <substance> and <unity>, becomes already pressing with Locke, it was Kant’s reading of Leibniz’s Nouveaux Essais that properly put this problem on Kant’s agenda. I argue that the first Critique’s Metaphysical Deduction of the Categories, in connection with some material from their Transcendental Deduction, constitutes Kant’s answer to this Leibnizian form of the Lockean question for the origin of conceptual content. First, I collect and analyze material from Leibniz, Locke, and Descartes regarding their shared albeit differently elaborated views of reflection on the mind as the source of metaphysical concepts. This leads me to the diagnosis of an explanatory circle common to these early modern views before Kant. Then, I reconstruct how Kant developed a series of insights from his predecessors Descartes, Locke, and Leibniz into his own view of reflection on the understanding as the origin of metaphysical concepts. I conclude that his view can avoid the explanatory circle. In particular, a novel connection of two Lockean thoughts helps yield Kant’s answer to the Leibnizian form of the Lockean question: first, that a reflection on representational acts explains the contents of metaphysical concepts, similar to a Lockean reflection on ideas and operations in inner sense; second, that these acts, more specifically, are acts of combination required for the representation of objects of experience and their features, similar to a Lockean combination of simple into complex ideas. The representational contents of Kant’s categories, as the most fundamental concepts of an object in general, are based on a reflection on acts of synthesis exercised in experiences of objects. 

Mit der Renaissance der Metaphysik in den letzten Jahren hat sich auch die Reflexion auf ihre Grundlagen intensiviert. Die auf Kant zurückgehende Frage nach der Möglichkeit der Metaphysik jedoch, so scheint es, bleibt in diesen Auseinandersetzungen dennoch weitgehend außen vor. Zwar steht diese Frage im Hintergrund, wenn zum Beispiel darüber diskutiert wird, ob wir das Unternehmen der Metaphysik realistisch oder nicht-realistisch auffassen sollten. Nach einer unmittelbaren Auseinandersetzung mit der Frage jedoch, unter welchen Bedingungen realistisch verstandene Metaphysik möglich ist, suchen wir meist vergebens. Realistisch verstandene Metaphysik untersucht die allgemeinste Form der Welt (oder Realität, Wirklichkeit usw.). Wie ist eine solche Untersuchung möglich? Metaphysik, die auch ihre eigene Möglichkeit zum Thema macht, ist eine dem Anspruch nach kritische Metaphysik. Wir glauben, dass Metaphysik nur dann ihre eigene Möglichkeit thematisiert, und also den Anspruch erhebt, kritisch zu sein, wenn sie in ihrer Untersuchung der Form der Welt auch eine Untersuchung der allgemeinsten Form des Denkens ist. Ohne eine Untersuchung der Form, die Denken als Denken der Welt aufweist, kommt die Frage nach der Möglichkeit der Metaphysik, nach der Möglichkeit des Denkens der Form der Welt also, gar nicht erst in den Blick. Nur, wenn das Verhältnis der Form des Denkens und der Form der Welt Gegenstand der Überlegung ist, kann Metaphysik den Anspruch erheben, kritisch zu sein. Wie wir dieses Verhältnis genauer zu beschreiben und verstehen haben, muss Gegenstand der Auseinandersetzung über ein angemessenes Verständnis kritischer Metaphysik sein. Einer solchen Auseinandersetzung soll hier Raum gegeben werden. Der vorliegende Schwerpunkt ist der Versuch einer Bestandsaufnahme kritischer Metaphysik in der deutschsprachigen Gegenwartsphilosophie. Wir verstehen ihn als eine Plattform der Auseinandersetzung darüber, wie der Anspruch, kritische Metaphysik zu betreiben, überzeugend erfüllt werden kann – als eine Plattform der Auseinandersetzung über ein angemessenes Verständnis kritischer Metaphysik also.

In the Critique of Pure Reason, Kant develops a metametaphysical view concerning the domain and source of a distinctively metaphysical cognition of objects of experience, which is given in terms of an analysis of our representational capacity for thought, namely, the understanding, regarding its sub-capacities and their constitutive abilities and acts. In the Analytic of Concepts, more precisely, in the Metaphysical and Subjective Deductions of the Categories, Kant develops an elaborate account of the content and formation of those metaphysical concepts of an object in general through which there is genuine philosophical cognition of objects of experience, namely, the categories. Relating the Analytic of Concepts to the Doctrine of Method, I give a detailed reconstruction of this account in contrast to both empirical and mathematical concepts. I do so by establishing, for the first time (in English) that and how the representational contents of the categories, as general representations of objects, derive from fundamental abilities and acts of a synthesis of an empirical intuition that the understanding contributes to experiences of objects, which thus yield the original contents of the categories. In particular, I argue that the threefold synthesis of the fundamental act-types of the apprehension, reproduction, and recognition of a manifold of sense-impressions, presented in the A-Deduction, holds the key to understanding the origin of the categories, or concepts of an object in general, investigated in their Metaphysical Deduction. It turns out that the threefold synthesis, as it is exercised regarding a manifold of sense-impressions in an empirical intuition of an object, can indeed account for the representational contents of the categories of Quality (apprehension), Quantity (reproduction), Relation (recognition), and Modality (relating to the object through a manifold of sense-impressions). In this sense, the categories are “concepts of synthesis” (A80/B106) or “concepts of the synthesis of possible sensations” (A723/B751).

In his final monograph, Barry Stroud argues that certain fundamental concepts, like the concept of causation, are not only indispensable to any thought of an objective, independent world, but that they are also, therefore, invulnerable to skeptical attack. Given some assumptions about thought and objectivity, this leads him into the following metaphysical aporia: We can neither metaphysically establish that the objective, independent world is as we must think of it nor that it is not that way. I will argue that the source of this aporia is a notion of objectivity in terms of the complete independence from any relation to thought whatsoever. This is a notion never explicitly argued for, as Stroud does not identify its origin. I then argue that a Kantian notion of objectivity can both be justified by tracing it to its origin in what we understand thinking and perceiving to be and dissolve Stroud’s aporia. If there is a way we must think of the world, and if we conceive of this world as completely independent of any relation to thought, then it is indeed hard to see why the world would agree with the fundamental form of thought. But if the objective, independent world is instead conceived of in relation to thought rather than independently of it and in terms of the independence from subjects and acts of thinking and perceiving, then it becomes intelligible how the world in relation to thought can agree with our fundamental concepts, while the world independent of any relation to thought might not.

What are thoughts, or propositions, exactly? I develop an answer to this question in relation to the Russellian and Fregean views – propositions as facts and propositions as contents –, defending a Kantian alternative: propositions as acts. I move from natural or naïve Russellianism and its difficulties to more sophisticated and promising Fregeanism, which can respond to these difficulties but only at the expense of leaving open serious explanatory gaps of its own. Along the way, I develop Kantianism as incorporating what is promising in Fregeanism while closing the gaps this view left open, and present it more systematically at the end.

This book develops a textually grounded reconstruction of Kant’s argument in the Metaphysical Deduction. The argument proceeds in three steps, developing, first, a concept of judgment on which to base the table of logical functions, next a concept of synthesis of intuition that explains the content of the categories, and finally a concept of the understanding on which the categories belong a priori to the same capacity through which we judge. The investigation presented here is an argumentative reconstruction of Kant’s text. The text in question is the "Guiding Thread to the Discovery of all Pure Concepts of the Understanding" in both the 1781 (A) and 1787 (B) editions of the Critique of Pure Reason (A64-83/B89-113). To illuminate Kant’s considerations in this chapter, the reconstruction also draws on passages from elsewhere in the Critique, from Kant’s writings after the Critique, as well as notes from his Nachlass and student transcriptions of lectures he held during and subsequent to writing the Critique. Four passages, in particular, are of central importance: (i) the retrospective description of the task of the Metaphysical Deduction at B159, (ii) the retrospective description of the procedure of the "Guiding Thread" at A299/B355f., (iii) the section "On the A Priori Grounds for the Possibility of Experience" in the A-edition Transcendental Deduction of the Categories (A95-110), and (iv) §§15-21 in the B-edition Transcendental Deduction (B128-148). The present interpretation of the Metaphysical Deduction thus emerges from a detailed and comprehensive analysis of the "Guiding Thread" that draws on related passages from the indicated portion of Kant’s corpus and, especially, on the aforementioned four passages from the Critique. Viewing these texts together and in a specific relation to one another suggests a reading which leaves little room for doubt. This sort of textually sensitive but charitable reconstruction helps to bring out the enduring force and interest of Kant’s philosophical position. Reviews “A fourth major monograph can now be added to this list [of the classic monographs on the Metaphysical Deduction as such: Reich 1932, Brandt 1991 and Wolff 1995, besides the masterful Longuenesse 1998]: Till Hoeppner’s Urteil und Anschauung. Kants metaphysische Deduktion der Kategorien. Crucially, unlike those aforementioned three books, but like Longuenesse, Hoeppner includes an extensive, separate account of the all-important third section of the Metaphysical Deduction, that is, the section leading up to the table of categories (§10, A76–80/B102–6). […] [T]he interpretative support, internal and external to the actual text of the Metaphysical Deduction, that Hoeppner does muster in support of his reading is impressive. His analysis of Kant’s arguments for the central claim that the elements that make up the conditions of thought are exactly congruent to the functions of judgment, as well as his intriguing and, at first pass, persuasive account of the categories as having the threefold act of synthesis as their representational content (330 et passim) are rigorously argued, exceedingly detailed and frequently illuminating. […] Much more of course can be said about Hoeppner’s excellent book, and I am certain many scholars of Kant will benefit from its extensive and detailed analyses of an often still largely misunderstood chapter in Kant’s Critique of Pure Reason.” —Dennis Schulting, Kantian Review　28　(4):　640–644.　 [For Dennis Schulting's review for "Kantian Review" see under "External Links" below.] -- Wie hier durch textnahe und argumentative Rekonstruktion erstmals gezeigt wird, entwickelt Kant in der Metaphysischen Deduktion in drei Schritten: (i) einen Begriff des Urteils, auf dem die Tafel logischer Funktionen beruht; (ii) einen Begriff der Synthesis der Anschauung, der die Inhalte der Kategorien erklärt; und (iii) einen Begriff des Verstandes, demzufolge die Kategorien a priori zu demselben Vermögen gehören, durch das wir auch urteilen. Die vorliegende Untersuchung ist eine argumentative Rekonstruktion von Kants Text. Der rekonstruierte Text ist der „Leitfaden der Entdeckung aller reinen Verstandesbegriffe" auf A 64 bis 83 / B 89 bis 113 der Kritik der reinen Vernunft in ihren beiden Auflagen von 1781 (A) und 1787 (B). Zudem werden andere, für ein Verständnis der Überlegungen in diesem Kapitel erforderliche oder zumindest erhellende Textstellen aus der Kritik herangezogen; aus Schriften, die Kant nach der Kritik geschrieben hat; sowie schließlich aus Kants Nachlass-Notizen und aus Nachschriften zu seinen Vorlesungen jeweils seit der Entstehungszeit der Kritik. Von entscheidender Bedeutung sind dabei vor allem vier weitere Passagen der Kritik selbst: i) die rückblickende Beschreibung der Aufgabe der Metaphysischen Deduktion auf B 159, ii) die rückblickende Beschreibung des Vorgehens im „Leitfaden" auf A 299/B 355 f., iii) der Abschnitt „Von den Gründen a priori zur Möglichkeit der Erfahrung" auf A 95 bis 110 der Transzendentalen Deduktion der Kategorien in der ersten Auflage und schließlich iv) die §§ 15 bis 21 auf B 128 bis 148 der Transzendentalen Deduktion der Kategorien in der zweiten Auflage der Kritik. Vor dem Hintergrund einer umfassenden und detaillierten Analyse des „Leitfadens", bei Hinzuziehung verwandter Stellen aus dem umgrenzten Textbestand und nicht zuletzt bei Berücksichtigung des Verhältnisses des „Leitfadens" zu den genannten vier Passagen der Kritik legt sich eine Interpretation der Metaphysischen Deduktion nahe, die sich nur schwer bestreiten lässt, sobald diese Texte einmal gemeinsam betrachtet und auf eine bestimmte Weise zueinander ins Verhältnis gesetzt werden. Dabei kann eine durchgehend wohlwollende, argumentative Rekonstruktion dazu beitragen, auch die philosophische Überzeugungskraft der Position Kants deutlich zu machen. Reviews “A fourth major monograph can now be added to this list [of the classic monographs on the Metaphysical Deduction as such: Reich 1932, Brandt 1991 and Wolff 1995, besides the masterful Longuenesse 1998]: Till Hoeppner’s Urteil und Anschauung. Kants metaphysische Deduktion der Kategorien. Crucially, unlike those aforementioned three books, but like Longuenesse, Hoeppner includes an extensive, separate account of the all-important third section of the Metaphysical Deduction, that is, the section leading up to the table of categories (§10, A76–80/B102–6). […] [T]he interpretative support, internal and external to the actual text of the Metaphysical Deduction, that Hoeppner does muster in support of his reading is impressive. His analysis of Kant’s arguments for the central claim that the elements that make up the conditions of thought are exactly congruent to the functions of judgment, as well as his intriguing and, at first pass, persuasive account of the categories as having the threefold act of synthesis as their representational content (330 et passim) are rigorously argued, exceedingly detailed and frequently illuminating. […] Much more of course can be said about Hoeppner’s excellent book, and I am certain many scholars of Kant will benefit from its extensive and detailed analyses of an often still largely misunderstood chapter in Kant’s Critique of Pure Reason.” —Dennis Schulting, Kantian Review　28　(4):　640–644.　 [Für Dennis Schultings Rezension für "Kantian Review" siehe unten unter "External Links".]

This paper offers a new account of Kant`s metaphysical deduction of the categories in the Critique of Pure Reason. This is accomplished by way of a new interpretation of Kant`s notion of function and his theory of mental activity, which is presented in terms of a logic and theory of intentional reference. A detailed discussion of the definition and use of the notion of function in the “Leading Thread” leads to an interpretation of the notion of function as a complex, triparted unity of intentional reference. Kant´s thesis that the unity of judgment and the unity of intuition rest on the very same function is thus explained as the thesis of the structural identity of analysis and synthesis. The presented interpretation of the notion of function and the corresponding theory of intentional reference make it possible to deduce the titles of quality, quantity, and relation of the tables of judgments and the categories, and to justify their necessity. The conception of a logic of reference to particulars then establishes the respective three moments of these titles. The title and the moments of modality finally are grounded in the cognitive constitution of finite beings. Thus Kant`s claim for completeness of the tables of judgments and the categories can be elucidated as well as justified. -- Die vorliegende Abhandlung bietet einen neuen Zugang zu Kants metaphysischer Deduktion der Kategorien in der Kritik der reinen Vernunft. Erreicht wird dieser vermittels einer Neuinterpretation von Kants Begriff der Funktion sowie seiner Theorie mentaler Aktivität, die als eine Logik und Theorie intentionalen Bezugs dargestellt wird. Eine detaillierte Untersuchung der Definition und Verwendung des Begriffs der Funktion im „Leitfaden“ führt zu einer Interpretation des Begriffs der Funktion als komplexe, dreiteilige Einheit intentionalen Bezugs. Kants These, dass die Einheit des Urteils und die Einheit der Anschauung auf derselben Funktion beruhen , wird auf diese Weise als die These der strukturellen Identität von Analysis und Synthesis verständlich gemacht. Die vorgelegte Interpretation des Funktionsbegriffs sowie die entsprechende Theorie intentionalen Bezugs ermöglichen es, die Titel der Qualität, Quantität und Relation der Urteils- und Kategorientafel herzuleiten und ihre Notwendigkeit zu rechtfertigen. Die Konzeption einer Logik des Bezugs auf Einzeldinge begründet dann die jeweils drei Momente dieser Titel. Der Titel und die Momente der Modalität schließlich haben ihren Grund in der kognitiven Verfasstheit endlicher Wesen. Auf diese Weise kann Kants Anspruch der Vollständigkeit der Urteils- und Kategorientafel sowohl verständlich gemacht als auch begründet werden

We begin by considering two common ways of conceiving critical metaphysics. According to the first (and polemical) conception, critical metaphysics analyzes nothing more than the form of thought and thereby misses the proper point of metaphysics, namely to investigate the form of reality. According to the second (and affirmative) conception, critical metaphysics starts from the supposed insight that the form of reality cannot be other than the form of thought and is thus not required to analyze anything but that form. We argue that the first conception is too weak while the second is too strong. Then we sketch an alternative conception of critical metaphysics, a conception we find expressed both in Kant’s B-Deduction and in the way Barry Stroud has recently investigated the possibility of metaphysics. According to such a conception, a properly critical metaphysics needs to proceed in two steps: first, it needs to analyze the most general and necessary form of any thought that is about an objective reality at all; second, it needs to investigate how that form of thought relates to the reality it purports to represent. But unlike Kant, Stroud remains sceptical regarding the possibility of a satisfying transition from thought to reality in metaphysics. We argue that this dissatisfaction can be traced back to a notion of objectivity and reality in terms of complete mind-independence. Then we sketch an alternative notion of objectivity and reality in terms of distinctness from subjects and acts of thinking, and argue that it is that notion that allows Kant, with his Transcendental Idealism, to make the transition required for any satisfying metaphysics, namely that from the form of thought to reality.

Kant’s Metaphysical Deduction of the Categories justifies their apriority, i.e. that their contents originate in the understanding itself, while the Transcendental Deduction justifies their objectivity, both in that they purport to represent objects of experience and that they do so successfully. The apriority of the categories, as explained in terms of acts of synthesis required for having sensible intuitions of objects, is justified by establishing their generic identity with logical functions of judgment, i.e. acts of judgment required for referring concepts to objects. The objective purport of the categories is justified by establishing that sensible intuitions fall under them. To finally justify that the categories represent successfully, i.e. that the objects of our intuitions fall under them, it is established that the representations of space and time do, namely by showing that the features addressed in their Metaphysical Expositions, too, are to be explained in terms of acts of synthesis.