When Kant wrote the Critique of Pure Reason in 1781, he addressed the question of the status of metaphysics itself. It had fallen into low regard in the previous century or so, struggling to keep up with advances in mathematics and the sciences and easily co-opted for dogmatic or oppressive projects. Kant’s own view was that one had to work harder than one would have liked to distinguish metaphysics from pseudo-science or occultism. As he pointed out, this hadn’t always been the case. Not only had metaphysics previously been regarded as a genuine science but in fact it had been the preeminent one, the ‘queen of the sciences’ (Aviii). Part of Kant’s project in the Critique was a glorious revolution whereby metaphysics was returned to the throne. Metaphysics subsequently transformed—seemingly overnight—from having a defensive inferiority complex to a new self-image of effortless superiority. The manner in which Kant executed this restoration project was by re-imagining inquiry itself in terms of the operations of the powers of the mind involved in that inquiry. Whereas other sciences were understood as occasions of human rationality applied to some distinct subject matter, philosophical inquiry was properly understood as rationality inquiring into itself. Philosophy’s inherently self-regarding character, so long a ground of suspicion against it, was now the very thing that entailed that metaphysics could occupy the highest position in the hierarchy of the sciences.
At the heart of Kant’s Critical project then is the drama of that inquiry as the exercise of rationality’s ‘self-cognition’ [Selbsterkenntnis] (Axi, A735/B763, A849/B877). It is this exercise of rationality in general that is the topic of Karl Schafer’s excellent book. Kant’s Reason is part of a relatively recent trend in Kant scholarship towards more general thematic approaches, offering to reframe how we understand Kant’s thought overall. Schafer sets out an overview of Kantian rationality that—amongst many other things—makes sense of the differentiation between theoretical and practical rationality; the way in which both are nevertheless in an important sense united in a single conception of rationality; how despite this, practical reason can be granted a kind of primacy over the theoretical; and in so doing he includes a reading of Kantian rationality’s inherent limitations. As well as all this, and although he is not offering an overall philosophical defence, Schafer also details much that he regards to be of contemporary value in Kant’s conception of rationality.
After setting out the project in an extended introduction, the book proceeds in seven chapters. Ch. 1 outlines the broadly constitutivist ‘capacities-first’ framework within which Schafer works; Ch. 2 outlines the type of capacity at play, and argues that it is one whereby a capacity aims at cognition [Erkenntnis] alongside a self-conscious, if often implicit, awareness of the standards for correctness for that cognition; Ch. 3 describes how this position is properly characterized as meta-normative constitutivism and how it differs from some other versions of constitutivism; Ch. 4 argues that the form of cognition involved in Kant’s capacity-first constitutivism ought to be specified to the epistemic achievement of comprehension (of which more below) and that comprehension is relative to the ends of rationality, which thereby allows for different capacities to be viewed as both unified and suitably differentiated; Ch. 5 argues that Kant’s ‘supreme principle of reason’, which expresses the demand for something unconditioned that grounds everything conditioned, and which articulates this end of comprehension, can be thought of as a variant of the Principle of Sufficient Reason (PSR). Schafer claims that in the theoretical context Kant argues for a positive, if modest, epistemic attitude towards the existence of something unconditioned; in Ch. 6 Schafer extends this analysis to the practical domain, showing how the Kantian variant of the PSR leads to Kant’s formulas of universal law and of humanity; in Ch. 7 he claims that the unity of these different manifestations of the Kantian supreme principle can be secured if both are considered as expressions of human rationality’s autonomy in securing comprehension; Kant’s Reason concludes with a discussion of some of the prospects and potential limitations of this conception of rationality.
Because of the sweep of the project and the density of the subject matter, substantive signposting and frequent recapitulation of results is necessitated, but the clarity of Schafer’s writing keeps things moving along nicely.[1] One other feature of Schafer’s writing that must be noted is his assiduous and generous acknowledgement of intellectual debts and alignments of position within a crowded academic landscape. Kant’s Reason manages to be both wide-ranging and intellectually dense simultaneously. As can be seen, there is a huge range of topics explored and argued for in this work, and it will certainly be relied upon for years to come as required reading. Any review will have to ignore more of the details than it ought, and I’ll also take a thematic approach for the general reader and will pick one issue that struck me as being of particular interest. This concerns the methodological question of how one reads the First Critique and how this might relate to how one subsequently interprets Kant’s relationship with rationalist metaphysics, and in particular his attitude toward the PSR.
Since at least the time of Jacobi’s ‘Über das Unternehmen des Kriticismus, die Vernunft zu Verstande zu bringen, und der Philosophie überhaupt eine neue Absicht zu geben’ in 1802, there has been a concern regarding Kant’s conception of rationality relating to his division of labour between the individual cognitive faculties of understanding and reason. Understanding is that faculty which (in combination with the faculty of sensibility) secures theoretical a priori cognition, and in so doing also sets demanding restrictions on the status of metaphysical claims, restricting propositions with ‘sense and significance’ [Sinn und Bedeutung] to applications of concepts within the spatiotemporal domain. Concepts such as causation find full expression just when reconceptualized as nomological characterizations of phenomena, much as a post-Newtonian model of inquiry might have seemed to invite. Reason is a higher-order capacity that through more elaborate inferential activity sets ends for human inquiry, represents nature as a whole rather than as a mere aggregate of law-like generalizations, and reveals to the inquirer prospects for grasping the overall sense and value of that inquiry.
A quick bit of internal critique threatens to reveal a dilemma regarding the normative authority of the faculties. On the one hand, it seems that understanding is superior to reason, since reason’s reachings are denied the status of a priori cognition by virtue of epistemic restrictions set by understanding; on the other hand, it seems that reason’s demands are the trumping ones, since although only understanding can secure such epistemic results, it looks as if only reason can articulate just what these results are for (so to speak), since it is reason that articulates the value and purpose of such achievements, as well as being the capacity that puts those achievements into some systematic order such that we can make sense of those achievements considered collectively. For example, if understanding really has the whip hand, then it denies ‘sense and significance’ to teleological representations. Although reason should be permitted such representations perhaps (since according to Kant the representation of ends emerges naturally from that capacity’s structure and activity) it’s harder to see why understanding should really feel bound to obey them. On the other hand, if reason really has the whip hand, and if understanding should in some sense be subordinated to reason’s demands, then it’s hard to see why one should have felt quite so strongly about all those apparent epistemic and semantic restrictions previously set by the understanding.
Although Schafer’s work does not proceed on the basis of negotiating this dilemma, it might provide a useful context for considering some aspects of the original and wide-ranging interpretation that he offers. Schafer claims that for Kant reason was a capacity for a specific kind of epistemic achievement, namely, a form of systematic understanding Kant calls ‘comprehension’. ‘Comprehension’ is a technical term for Kant, one that occupies the top of a hierarchy of ideal human cognitive achievements. The hierarchy, it seems, is progressive such that comprehension entails having secured the lower stages of epistemic relations to its target. The point is important, because it means that comprehension of x, which is a form of understanding, entails cognition of x. Whereas ‘cognition’ [Erkenntnis] isn’t synonymous with ‘knowledge’ [Wissen] for Kant, the former involves some positive aspects of what contemporary conceptions of knowledge include—cognition involves the direct presentation to consciousness of some kind of object in a way that puts the subject in an epistemic position that enables what we would call knowledge and understanding. Schafer’s interpretation could perhaps defuse Jacobi’s concern by virtue of its compelling stress upon the ‘end-relative’ nature of Kantian rationality (120). Each of the faculties secures its own normative authority by virtue of there being different goals for comprehension set by our epistemic and existential interests. The powers of Kantian rationality aim at comprehension in different fields, and when this is understood, its operations can be understood as compatible and, moreover, unified. For example—and skipping over the details considerably—it emerges on Schafer’s view that although we cannot theoretically comprehend our freedom we can practically comprehend it, which is to grasp freedom’s explanatory value relative to our moral ends.
This understanding of Kant’s position might seem unfamiliar to those used to traditional pictures of Kant as primarily a scourge of rationalist metaphysical visions of powers. For Schafer, the ‘power’ involved with capacities-first constitutivism brings with it no particular ontological commitments, however. In keeping with some more recent scholarship, however, Schafer takes a ‘Dialectic-first’ interpretive approach (1, fn. 2, following Kreines 2002). On such a reading issues concerned with the positive operations of reason in the Transcendental Dialectic (found later in the text of the Critique) are nevertheless given interpretive priority in terms of one’s view of the overall project. Such a reading allows the reader to consider Kant’s talk of reason’s powers and ends not as an extended afterthought to the main event but rather as central to Kant’s original Critical vision.
One thing that, perhaps inevitably, gets downplayed with such an approach is the degree to which Kant’s transcendental critique can be seen as inviting a metaphilosophical re-conceptualisation of metaphysical principles via considerations of the philosophy of mind. On what one might call an ‘Analytic-first’ approach, one reads the text progressively, taking later sections in the light of the results of earlier ones. On this reading Kant is first offering a regimented philosophical semantics based on the constraints of a mind’s possible spatiotemporal representation, and any subsequent philosophical assertions—including Kant’s own in the Transcendental Dialectic—must be read under those same constraints. What this might mean is that when, for instance, Kant talks about reason as committing us to a mere ‘object in the idea’ (A671/B699) he is offering an account of how the content of whatever it is that is being asserted there should be reassessed. Moreover, he is saying it ought to be reassessed as in fact expressing something about the human mind’s activities. On a Dialectic-first approach, such semantic constraints are superseded by higher interests, and so the subjectivity of talk of ‘object in the idea’, etc. affects not the content of the idea, which one can now rather take at face value, but instead only the status of the epistemic grounds upon which that content can be asserted. On the Dialectic-first approach that Schafer supports, Kant’s attack on rationalism is primarily an attack on its epistemology, not its metaphysics.
One question is whether this approach does due justice to the re-conceptualization of metaphysics Kant may have intended. In uncovering the principle of causality as a principle of experience, i.e., of the time-determination of spatial representation, Kant invites the reader to think a more radical thought, which is the genealogical dimension to Kant’s account of metaphysical theorizing. Were his account correct, then all we might have ever perspicuously meant when deploying the PSR in metaphysics was some misguided extension of our causal thinking in experience (as Schafer notes, possible gestures at this thought can be found at e.g., A201/B245 and at A217/B265). One could alternatively take it to be the case that Kant has an independent commitment to the variant of the PSR and is in the Second Analogy merely stipulating the conditions under which an application of that principle can generate certain specific epistemic returns. However, Kant identifies his ‘supreme principle of reason’ as relating to a logical principle that is not itself identical to the PSR, and he makes no similar gesture relating the PSR to the supreme principle, as one might have thought he would. Given that Schafer acknowledges that Kant’s variant involves deviation from the PSR as rationalist metaphysicians would recognize it, one wonders what would be lost from Schafer’s overall view if his claims regarding the PSR were rejected. From this perspective, the main appeal of seeing the supreme principle of reason as a version of the PSR is that it chimes with a Dialectic-first approach and a willingness to see continuities between Kant and his rationalist predecessors.
Resistance to this Analytic-first reading perhaps stems from a worry that it seems to attribute to Kant a verificationism regarding meaning that he didn’t hold. Another reason to resist this reading is that it threatens to attribute to the Critiquean overpowered debunking agenda. This seems true, though Kant’s Critical approach can just as surely seem overpowered despite itself if Kant’s own end was that we accept reason’s core recommendations without suspicion. For example, in the Groundwork, Kant says that ‘where determination by laws of nature cease, there all explanation ceases as well’ (4: 459), yet this must not be strictly true if reason’s capacity for comprehension explains something when practical comprehension is achieved. It’s similarly unclear as to why the supreme principle of reason itself can be admitted as synthetic a priori, if all synthetic a priori principles are valid only by appeal to the possibility of spatiotemporal experience. A more positive reason to resist the Analytic-first reading is that it perhaps puts Kant in keeping with a lineage of a kind of perennial philosophy, where reason, truth, fundamental reality, the good, and self-knowledge are all in some way aligned concepts. Yet, whatever the appeal of such a reading, it surely needs to be qualified by making good sense of how Kant’s project aims for a rejection of transcendental realism (one of the few core Kantian concepts not extensively discussed in Schafer’s work), the metaphilosophical presupposition that gives the inquirer such alignments for free. On Dialectic-first readings, the human mind seems to get most of the mind-reality alignments that the rationalist originally envisaged, just with a humble readjustment of the epistemic relations one is enjoying when one is so aligned.
I have tried to raise some Jacobi-like questions regarding Schafer’s approach in Kant’s Reason. It is to ask too much, given its focus, to inquire as to what Schafer might have said about the prospects for Kantian rationality outside of the test case of contemporary metaethics (and also with regard to social and political critique, where he also sees some promise). Certainly, Kant himself saw such practical payoffs, but he seems to have also been motivated by the prospects for accommodating the reality of post-Newtonian scientific practice, not to mention securing the unity of the sciences. It would be interesting to think about whether or how this Kantian model of rationality might accommodate in an illuminating way cases where other forms of reasoning appear central, such as with statistical reasoning in quantum mechanics, etc. If one would like the metaethical payoffs without the ambitions that might now strike us as grandiose, one would then be seeking the advantages of Kantian rationality without the broader applications or the triumphalist status of metaphysics that Kant thought that it entailed. This, though, is to mention just one of the core themes in Kant’s thought brilliantly explored in Schafer’s book.
REFERENCES
Kreines, James (2022). For a Dialectic-First Approach to Kant’s Critique of Pure Reason. Open Philosophy 5 (1):490–509.
[1] Some tighter copy-editing by OUP would have been preferable however—for one example, two sentences from pages 147–8 are repeated again on page 148.
Reviewed by John Callanan, King’s College London