Lorini’s monograph, the English title of which is The Sources and Lexicon of the Kantian Ontology: The Lectures on Metaphysics (1762–1795), closely examines the development of the complex intersections between metaphysics, transcendental philosophy and ontology. As the title suggests, it analyses the development of Kant’s terminology (lessico), quoting terms in Latin or German, while drawing from the lectures (Vorlesungen) to add to what we know from Kant’s published writings, marginalia and correspondence. While the title might lead one to expect the book to focus on Kant’s lectures nearly exclusively, this is not the case; rather, the lecture transcriptions are used mostly as a supplement to a chronological examination of Kant’s publications, and the majority of the discussion of Kant actually attends to the published works. When it does turn to the lectures, the book makes references to the lectures on metaphysics from 1762 to 1795 (above all, Metaphysik Herder, L ₁, K ₁, Mrongovius, Volckmann, von Schön, L ₂ or Pölitz, Dohna, K ₂, and K ₃ or Vigilantius). There are also some references to several of the courses on logic, anthropology, moral philosophy, philosophical encyclopedia, rational theology and physics.

The book opens with an Introduction, contains three long chapters, and ends with a section called ‘Conclusions’, including a brief discussion of ontology in the Progress essay. The study aims to discuss how Kant’s courses on metaphysics can help us better understand his complex (and developing) relation to ontology. Lorini argues that Kant engages in and contributes to ontology, and holds that this is more apparent in his courses on metaphysics than in the published works. Significantly, the cover flap quotes the following passage from the Progress (20: 260), where Kant, finally, is more explicit about his commitment: ‘Ontology does not impinge on the supersensible, which nonetheless is the final aim of metaphysics, and thus belongs to metaphysics only as a propaedeutic, as a hallway or vestibule of proper metaphysics’. But the flap omits rest of the passage: ‘and is called transcendental philosophy, because it contains the conditions and first elements of all our knowledge a priori’. Now, what does it mean to say that ‘ontology’ is called ‘transcendental philosophy’, and how precisely are each of these terms defined? Kant does not always use the terms consistently. Is the claim best understood as an identification of the two (extensional equivalence), an analogy, a mere interaction between them or as something else? These are the kinds of the questions this book raises, although its answers are not always as clear as they could be.

Reminiscent of the work of Giorgio Tonelli (whom Lorini nearly always cites approvingly), the book aims to look at the historical origin of certain key Kantian terms (e.g. Gegenstand, Objekt, notion, Idee):

The lectures here function as a proper philosophical ‘laboratory’ in which Kant experiments with, tests and recasts his thoughts (p. 30), specifically, about the relation between ontology and transcendental philosophy. Lorini’s book can be seen as contributing to the history of ideas (or terms) and as a study of Kant’s development in relation to his predecessors and sources – Locke, Leibniz, Wolff, Baumgarten, Crusius – as well as to contemporaries such as Lambert and Mendelssohn. While skilfully documenting Kant’s trajectory, the book contains little second-order assessment of Kant’s arguments themselves.

Lorini’s examination of the lecture transcriptions should be placed in the context of a wider appreciation of the value of Kant’s lectures to understanding the content and development of his philosophy. For instance, two collected volumes (Clewis Reference Clewis2015; Dörflinger etal. Reference Dörflinger, La Rocca, Louden and de Azevedo Marques2015) recently examined Kant’s lecture notes, including the transcriptions on metaphysics, and in fact Lorini contributed a chapter on metaphysics to one of these. (Scholars who do not read Italian might look at his chapter in Dörflinger etal. (Reference Dörflinger, La Rocca, Louden and de Azevedo Marques2015) for a taste of the claims he develops in his book.) Lorini briefly cites these volumes in a footnote (p. 21, n. 32) but, despite a great deal of overlapping content, curiously does not substantively engage with them. (It bears mentioning that a Cambridge Critical Guide devoted to the metaphysics lectures (Fugate 2018) has subsequently been published, in which Huaping Lu-Adler discusses ontology as transcendental philosophy.)

A strength of Lorini’s book is the author’s awareness of classical and recent scholarship from several languages – Italian, German, French, English – even if these studies could have been more critically engaged. This breadth allows the author to see beyond narrow or fashionable readings that sometimes result from focusing on the literature of just one language, region or era. Thus, though often confined to the footnotes, there are ample references to E. Adickes, F. Paulsen, H. Heimsoeth, N. Hinske, M. Wundt and B. Falkenburg; H. J. de Vleeschauwer; K. Ameriks, M. Friedman and L.W. Beck; and G. Tonelli, A. Ferrarin, A. Nuzzo and R. Pozzo.

Lorini’s work proceeds as follows. An introductory section (pp. 11–31) surveys different ways of interpreting Kant as a metaphysician, reviewing the interpretations of Paulsen, Wundt and Adickes as well as Heidegger’s ontological-subjectivist interpretation and the epistemological reading associated with Marburg neo-Kantianism. Lorini rightly observes that we should use the transcriptions with proper caution, that is, only in the context of their relations to Kant’s published works and other writings (letters, Reflexionen). Yet he also thinks that the privileged access that the lecture notes offer ‘make them an indispensable material for studying the transformations of a concept such as ontology’ (p. 21). ‘In assessing the lectures, studying the technical terminology reveals itself to be a particularly efficacious tool’ (p. 22). Indeed, the terminology Lorini discusses is sometimes quite technical.

Chapter 1, ‘A Plurality of Guiding Threads’ (pp. 33–114), begins with a discussion of the metaphysical approach to Naturforschung as found in Kant’s work of the 1740s, Thoughts on the True Estimation of Living Forces. This is followed by an analysis of the ontologico-metaphysical terms in Wolff, Baumgarten and Crusius, a discussion that, while perhaps necessary, is a bit dry. Lorini discusses the logic and metaphysics of Wolff (including the principles of non-contradiction and of sufficient reason), the metaphysics of Baumgarten and the ‘psychologism’ of Crusius. Lorini next discusses the first Silent Decade (mid-1740s to mid-1750s), that is, the one beginning after True Estimation. Lorini correctly observes (pp. 71–2) that this silent period has fascinated scholars far less than the later decade of silence occurring between 1770 and 1781. Finally, the author discusses the New Elucidation and Kant’s metaphysical theory of substance (monad) in the Physical Monadology. ‘If a brief attempt to apply Newtonian principles to metaphysics appeared in the Nova dilucidatio, in the Monadologia physica the resort to Newton is exclusively limited to questions of natural philosophy, since the metaphysical structure involved in the Monadologia physica is still substantially Wolffian’ (pp. 112–13).

After 115 pages finally we get to the second chapter, ‘Methodological Primacy’ (pp. 115–69), where Lorini examines writings from the 1760s such as ‘Inquiry’, ‘The Only Possible Argument’, ‘Negative Magnitudes’, ‘Announcement’ (1765–6), and ‘Dreams’. Lorini discerns in this period a growing tension between formal logic (including the principle of identity) and empirical knowledge (p. 167). The chapter begins by discussing the tension between mathematics and metaphysics, especially in the Inquiry, where Lorini again discerns the influence of Newton (p. 128). The Inquiry is approximately coeval with the first lecture notes on metaphysics that are available to us, the transcription deriving from the winter semester 1762/63 and transcribed by J. G. Herder. Thus – after about 100 pages (or nearly half of the book, excluding back matter) – we finally come to an examination of one of the lectures suggested by the title. The Herder metaphysics lecture notes are crucial to Lorini’s project, and he makes frequent reference to the Herder Metaphysik. As Steve Naragon has observed (Reference Naragon and Robert2015: 40), the Herder notes are invaluable because (1) they are early, (2) they are the only notes that are early, (3) they come directly from the classroom, (4) they are our only notes with multiple drafts, (5) they are extensive and (6) they are Herder’s.

Lorini next discusses Kant’s reflections on space in Regions of Space (1768), as well as the sudden change of mind (Umwälzung) that occurred in 1769. Here Lorini takes into consideration the influence of Lambert and Mendelssohn, and looks ahead to the first Critique. ‘Thus, if between 1768 and 1770 space maintains its own absoluteness in the course of a general adherence to Newtonianism, space’s peculiar reality is specified in a sense that is surely propaedeutic to the subjective and transcendental ideality that will characterize it in the KrV’ (p. 163).

The third chapter, ‘From the Intellectualia to the Intellect: Transcendental Synthesis’ (pp. 171–218), thus turns to the Inaugural Dissertation and covers the 1770s. ‘If in the writing of 1768 the concepts of “reality” and “existence” were used by Kant in a way that was basically indistinguishable, in the Dissertatio existence as a singularity (singolarità) undergoes a strong devaluation since both the sensible and intellectual worlds emerge e natura mentis’ (p. 172). The chapter proceeds to examine the ensuing (second) Silent Decade. On account of the absence of publications, ‘the lectures [e.g. Metaphysik L ₁ and K ₁] and the correspondence play a crucial role in these years as unique testimonies of the theoretical elaboration that leads to the first edition of the KrV’ (p. 31). The lectures provide a ‘valuable resource’ for any attempt to reconstruct the formation and development of the critical philosophy in these years (p. 191). Lorini goes on to discuss Kant’s thoughts in the critical period, drawing from the 1780s metaphysics lectures such as Mrongovius, Volckmann and von Schön as well as later lectures stemming from courses that took place after 1790. Here again we find connections to ontology. ‘Transcendental logic, which results in the intellect’s transcendental reflection on its own activity, is the instrument that enables transcendental philosophy to reformulate the requirements of ontology’ (p. 216). Since he writes that transcendental philosophy ‘reformulates’ the demands of ontology, it would appear that Lorini does not propose an ‘identification’ of ontology with transcendental philosophy, but some other relation, though he never sufficiently specifies what that relation is.

The last section, ‘Conclusions: Metaphysics in Light of the Transcendental’ (pp. 219–36), investigates three terminological terms (Notionen, Begriffe, Ideen), without however comparing them to their usage by other thinkers – Hegel comes to mind – or connecting to philosophy beyond Kant, as one might have expected of a conclusion. The Progress essay, Lorini holds, assigns a central role to ontology that Kant had previously made explicit only in lectures (pp. 231–2). Yet this section reads more like the other ones than as a genuine conclusion; it was not immediately clear which conclusions were meant to follow from the preceding sections. Perhaps it is that Kant ultimately, especially at the end of his philosophical career, and despite the facts that ‘ontology’ occurs rarely in his published writings and that the term plays no role in the Transcendental Dialectic, places the concept of ontology front and centre, and develops the concept of ontology (pp. 31, 206, 235–6). In some of the lectures, Kant designates transcendental philosophy as a kind of ‘ontology’ (p. 208). And even if Kant rarely uses the term in publications, ‘the scant use of a word does not necessarily imply scant relevance of the discipline it designates. If indeed posterity has often resorted to ontology in order to emphasize the sense and range of the methodological revolution that the Kantian transcendental stands for, it seems undeniable that an ontology is in any case always involved in critique’ (p. 235; cf. p. 17). The latter claim may indeed be true, but the author could have made a stronger case for why philosophers should consider it to be important, and in what, precisely, that claim consists.

The tracing of sources (fonti) can reveal important connections and philosophical debts, and looking at the history and development of key terms (or lessico) is potentially fruitful. Moreover, the historical and terminological investigations in Lorini’s book were carried out with rigour. Still, I could mention a few minor quibbles. The Conclusion section could have revealed where the author is situated in the aforementioned debate between interpreters such as Paulsen, Heidegger and the Neo-Kantians, but no such contribution was to be found. Moreover, it would have strengthened the book if it had offered more sustained and critical engagement with recent scholarship on its topic (beyond passing references in the footnotes), in order to see where the author disagrees with that scholarship and, more importantly, why he does so. Lastly, the book tends to see the phases in Kant’s intellectual development as steps in an inevitable ‘march’ toward the mature critical philosophy (e.g. 31, 175, 189) – though I admit that this is a temptation that is hard for any historical-developmental research to resist.

These reservations aside, one has to admire the scholarship and preparation that went into and made possible this well-documented and thorough book. It should be of interest to Kant scholars interested in the relation between ontology and transcendental philosophy, Kant’s method and the development of Kant’s thought about these and related themes.