The long-established genre of holistic interpretations of the Kantian philosophical project – interpretations that encompass Immanuel Kant’s overall aims in his critical philosophy – stands in contrast to the tendency in academic philosophy towards incremental developments occurring in a large number of well-delimited, specialized studies. This concise Spanish monograph Esquema, símbolo y tipo. Una aproximación al pensamiento de Kant (in English: Schema, Symbol and Type. An Approximation to Kant’s Thought) by Àlex Mumbrú Mora, published in late 2022, shows the influence that the holistic interpretation paradigm may still exert by harnessing recent developments in quite specialized areas of Kantian scholarship.

The book’s unified point of view on Kant’s philosophical project is attained from the unsuspected guiding thread of philosophy of language – and I say it is unsuspected because Kant’s explicit mentions of language are relatively scarce. Perhaps for this reason scholars have traditionally not counted language among Kant’s principal philosophical concerns. Yet, Mumbrú’s study takes its cue from a notion of semantics – understood as the search for the meaning of our concepts – which over the past few decades has increasingly been recognized in the specialized literature as the core of the Kantian ‘latente Sprachphilosophie’, its latent philosophy of language. Mumbrú argues that, in a Kantian framework, this semantic inquiry can equivalently be conducted via the three possible ‘particular-type’Footnote ¹ relations that Kant distinguishes: schema, symbol, and type (Typus).Footnote ²

How are these particular-type relations given? Now, on the one hand, in Critique of Judgement (§59, 5: 351-2) Kant distinguishes between schemata and symbols, which correspond to two modes of presenting concepts via intuition (hypotyposis). In the former case, the intuition is given a priori and corresponds to the concept given in the understanding; in the latter case, the concept or idea cannot be presented via an adequate intuition, yet, the rules of the procedures for apprehending the intuition and the concept are in agreement with one another (pp. 63-75). On the other hand, according to Kant, in his discussion of the Typic in the Critique of Practical Reason, the type (Typus) relates the moral law to its possible particularizations, namely, maxims of action (5: 69-71). These three ways in which particular–type relations are given (schema, symbol, and type (Typus)) correspond, respectively, to the theoretical, the aesthetic–teleological, and the practical areas of Kant’s philosophy. In other words, Mumbrú has come across a strikingly original yet natural way of presenting the division of the branches of Kant’s critical works.

The book comprises an introduction, eleven chapters, and a conclusion. Roughly, the introduction, chapter 1 and the conclusion form a unit where the overarching interpretative claims mentioned above are laid out and argued for. Chapters 2-11 include three subsequent units following the Kantian account of the meaning of our concepts via the particular-type relations furnished by schemata, types (Typus) and symbols, namely: our theoretical concepts (chapters 2-4), our practical concepts (chapters 5-9), and our aesthetic–teleological concepts (chapters 10-11).

Chapter 1 is devoted to answering what it means – and has meant in the literature since the 1970s – to study the philosophy of language in transcendental philosophy. I wish to highlight two of the ideas presented in this chapter that I find characteristic of the book as a whole. First, there is an initial assumption that establishes the framework for the rest of the monograph, namely, that in Kantian philosophy asking about the meaning of our terms is equivalent to asking about the meaning of our concepts (p. 5). Second, I wish to highlight the fact that the author sees no reason to follow a tendency that he deems to be specific to the Anglophone reception of Kant, namely, to limit the semantic inquiry in transcendental philosophy solely to the meaning of our theoretical concepts (p. 2). This tradition, according to the author, privileges the particular-type relation furnished by the schema, while for Kant this relation may also occur as a symbol or as a type (Typus), corresponding to the aesthetic and practical branches of philosophy, respectively.

Chapters 2 to 4 examine the meaning of theoretical concepts. Here, the particular-type relation is thought of as the relation between the intuition of an object (particular) and a universal representation of a concept (type). In chapter 2, the author explains the role of the schema of relating concepts to their characteristic marks (pp. 8-12), drawing on Kant’s logic lectures and the Critique of Pure Reason. Chapter 3 delves into how concepts are related to their objects in transcendental philosophy. By placing Kant’s position within a dialectical–historical discussion with Locke and Berkeley, the author unpacks the reasons why Kant opposes the view in which concepts arise, in essence, as copies of their objects. If this traditional account were correct, then an unsolvable dichotomy arises between Locke’s and Berkeley’s images, with both carrying implausible consequences: the former being overly indeterminate, and the latter overly particular. For Kant, the solution is furnished by the schema, namely, the general procedure that applies the universal rules of a given concept, particularizing it to its conforming object. In this characterization, the schema is understood as procedural and essentially active (pp. 13-18); the concept does not arise as a universalized copy of the object mediated by the mental image, but as applied to the object via the schema.

However, Kant’s position led to the charge that his theoretical philosophy reduces reality to mere appearance, which historically has proven to be one of the principal objections to Kant. Chapter 4 traces the evolution of this interpretative debate and concludes the part of the book devoted to Kant’s theoretical philosophy (pp. 19-26). After the Feder–Garve ‘Göttingen review’, Kant responded to his critics with a distinction in the Prolegomena between judgements of perception and judgements of experience. Due to their dependence on the transcendental principles of the understanding that make experience possible, judgements of experience are rendered objective, that is, they relate to objects. On the other hand, judgements of perception, such as ‘The room is warm’, do not aspire to anything other than subjective validity. According to Cassirer, Kant would have upheld this distinction so that features of appearances qua appearances are not confusedly endowed with objectivity, defending himself from the accusation of idealism à la Berkeley. Yet, on the basis of Cassirer’s reading of this distinction, Mumbrú points out that even formulating judgements of perception is problematic and the distinction becomes marred (pp. 22-3). While these judgements of perception do not claim to have more than subjective validity, their formulation involves representations (e.g., ‘warm’, ‘room’) that are nonetheless objectively apprehended under the unifying synthesis of the categories. For this reason, the author concludes the chapter by arguing that a phenomenological reading of Kant’s theoretical philosophy, such as the one that Heidegger presented in response to Cassirer, is a tenable development for coming to terms with these problems.

In fact, we can agree with the author’s argument, even without committing to Heidegger’s interpretation of Kant. Mumbrú’s point in these pages is that we can ‘understand Kant’s transcendental philosophy in the terms that Heidegger understands the phenomenological investigation, namely, as an “analytic description of intentionality in its aprioricity”’ (p. 24); in other words, the point is to inquire into how it is a priori possible for our concepts to be about things.

After chapter 5, the book changes gears to focus on Kant’s account of the origin and meaning of our moral and practical concepts. First, chapter 5 provides the transition from the theoretical to practical philosophy, situating the latter within the whole of Kant’s transcendental philosophy. In chapter 6, Mumbrú examines the categories of freedom as the pure concepts that make moral judgements possible. What is distinctive of the author’s treatment is that the categories of freedom are explained in their own right, bypassing the frequent dismissal by commentators on the grounds of Kant’s alleged penchant for symmetry (i.e., those who discredit this part of the second Critique for mirroring the categories of the understanding of the first). Chapter 7 explains how Kant determines the realm of right, that is, how actions performed by empirical subjects are subjected to juridical laws as deriving from the principle of universal right (p. 52). Mumbrú’s focus here is, first, on what makes the laws juridical and not moral, namely, the fact that they demand external conformity; second, on spelling out how the categories of freedom – according to quantity, quality, relation, and modality – supply the elementary notions with which we can think of such a thing as ‘juridical objectivity’.

Now, when actions are not merely considered externally but internally, that is, in the form in which they are willed, they are subjected to the moral law, which becomes the focus of chapters 8 and 9. In particular, chapter 8 describes Kant’s notion of type (Typus) from Kant’s Typic in the Critique of Practical Reason (5: 69-71). The type establishes the mediation between the purely rational moral law and the maxims of action, with the latter becoming the possible particular instantiations of the former. According to Mumbrú’s reading, because the fashion in which this mediation occurs renders types as a ‘quasi-schematism’ (p. 59), the Typic section accounts for the semantics of morality from the stance of transcendental philosophy. In short, types are what furnish maxims of action (as both expressions of and guidelines for particular courses of action) with moral meaning. Chapter 9 then takes up the categorical imperative in detail. In its context, it contributes to the book’s overall goals of providing an interpretation of all main branches of Kant’s philosophy. Yet, I will not further treat this chapter here since readers of this review are likely to be familiar with this material.

The final segment of the book spans chapters 10, 11, and the conclusion. Together, these final pages provide a systematic reunification both of Kant’s Critiques and of the topics the book delves into. How? Chapter 10 expounds the grounding transcendental perspective from which the functioning of the particular-type relations (functions for unifying diversities) must be established. Mumbrú emphasizes the practical side of the categories, focusing on Kant’s statement that the practical use of reason is nothing more than the very capacity to think (p. 68; KpV, 5: 65). The perspective attained is that of transcendental apperception, serving as the a priori foundation for all possible objects. Chapter 11 explores the areas of aesthetics and teleology, which are furnished by the symbolic particular-type relation. In the theoretical domain, Mumbrú explains, only concepts that may refer to possible objects of experience, when they are corresponded via schemata with intuition, yield cognition. Yet, our constitution is such that corresponding sensible intuitions are expected, even when it comes to pure non-theoretical concepts (p. 72), upon which Mumbrú reconstructs Kant’s explanation to the effect that aesthetics provides a symbolic exposition of moral concepts. From this perspective, Mumbrú discusses the idea of freedom, the benevolent will, moral sentiment, the Supreme Good, and aesthetic education. Finally, the conclusion of the book recasts the topics of each of the monograph’s chapters under the light of the semantics in Kantian philosophy.

There is room for criticism. I shall first start with a detail which, however small, has quite stood out to me. With the monograph’s subtitle, ‘An Approximation to Kant’s Thought’, Mumbrú is likely alluding to the particular-type theme of the book, via which we are carried closer to the fundamentals of Kant’s thought. However, the subtitle also leads to an expectation of an introductory work on Kantian philosophy. In truth, the monograph demands of its reader command of Kant’s thought and terminology, and it may not adequately serve as an introductory work. In short, my concern regarding this small detail is whether the title allows room for the wrong expectations.

Second, more justificatory and interpretative labour seems to have occurred behind the scenes in order to develop the book’s fundamental thesis than what the reader is let in on. Concretely, the type (Typus) is not considered a kind of hypotyposis in the Critique of Practical Reason, nor does it appear in the Critique of Judgement as one of the varieties of hypotyposis. By contrast, in Mumbrú’s reading, the three (schema, symbol, and type (Typus)) are treated as if, arranged together, they fulfilled or completed a single systematic need, and an argument for this way of considering the type (Typus) is indeed provided (pp. 55-9). Yet, a couple of alternative interpretations could rival the proposed one, for instance: that in the third Critique Kant rejected his previous position from the second; or that Kant never considered the type (Typus) as instantiating a relation akin to hypotyposis in the first place. While these are not likely to jeopardize the book’s core claims, these and other possibilities might have been discussed, if only to reject them. Another example involves the way in which the fundamental assumption of the book plays out. As mentioned above, Mumbrú’s study departs from the assumption that ‘to ask about the meaning of our linguistic terms is in Kant equivalent to the question of the meaning of our concepts, that is, the grounds for the hypotyposis relation’ (p. 92). This assumption is adopted systematically, without being discussed historically. In other words, while this assumption is upheld by referencing several passages from Kant’s writings, the author does not engage with the historical question about whether and how Kant’s position on this issue might have evolved. This need not be a problem were it not for the recent research suggesting that Kant’s views on the interrelation between language and thought did in fact shift (Forster Reference Forster2012). If this is so, then it seems that the book’s fundamental hypothesis calls for further qualification.

A third issue concerns the semantic themes that introduce, conclude, and determine the layout of the book: they become secondary in the middle chapters. Although their reintegration into the main premise does eventually occur in the book’s conclusion, I found myself regretting the occasions where an opportunity to strengthen the book’s thesis was missed (I find this especially occurs in the conclusion to chapter 4).

Notwithstanding, these criticisms are in fact prompted by a deep agreement with the author’s original thesis and a desire to see the flourishing of the multiple research avenues that it opens up. To say that my objections are outnumbered by the book’s virtues would be an understatement. Mumbrú upholds a standard where the holistic perspective on Kant’s philosophy works together with rather specialized topics in Kantian scholarship. The book’s semantic inquiry provides from a single elementary kind of relation an original unified approach for comprehending the branches of Kant’s philosophy. From this perspective, what at first appears to be a diverse table of contents, readily turns out to be a harmonious whole: the arranged structure of the book matches an analytical division of the topic it explores and also mirrors Kant’s de facto layout of transcendental philosophy. As a result, the book turns out to be an edifying achievement, managing to perceive both the forest and the trees.