While most work on Kant’s final, unpublished manuscript, the so-called Opus Postumum (OP) has focused on its relationship to his theoretical philosophy, and especially his philosophy of nature, Thorndike’s book instead uses an early section of OP (i.e. those leaves written between 1796 and 1798) to argue that Kant’s ‘Transition from the Metaphysical Foundations of Natural Science to Physics’ can help us to understand another transition, one within the practical sphere, that Kant was working on at the same time.
As his starting point, Thorndike uses a passage from the Metaphysics of Morals (MM) where Kant talks about both transition projects as analogous to one another (MM, 6: 468–9). Where the transition in the theoretical domain is from the metaphysical foundations of nature to empirical phenomena and aims to systematize empirical phenomena through the application of mediating concepts that schematize these metaphysical foundations, the transition in the practical domain is from the universal moral law to an agent’s diverse moral commitments and it aims to systematize these moral commitments through the application of mediating concepts that schematize the moral law. For Thorndike, the systematic goal of the transition project is not new, but rather lies ‘at the heart of the Critical Philosophy and had occupied Kant for many years’ (p. 237). Kant wants to establish the scientific status of both physics and ethics, but this requires demonstrating not only that their laws are apodictically certain, but also that their cognitions can be systematically unified (pp. 132–3).
These universal laws cannot apply directly to the particular and diverse phenomena they govern, however, and so must be schematized in the appropriate ways. When trying to understand what this schematism might involve, Thorndike cautions against relying on Kant’s account of the schematized categories in the Transcendental Analytic of the Critique of Pure Reason, but rather suggests that we examine the Transcendental Dialectic’s account of how the idea of a divine intellect schematizes the regulative principle of the systematic unity of nature allowing us to approach nature as if it were systematically unified (p. 86). As a continuation of Kant’s project in the Critique of Judgement, Thorndike argues that the transition schematizes these regulative principles through the use of reflecting rather than determining judgment (pp. 88–9). There is a gap between the metaphysical principles and the empirical phenomena that determining judgment cannot bridge. Reflecting judgement is necessary to generate the schemata that can bridge this gap. Unfortunately, according to Thorndike, Kant fails to bridge this gap either in the theoretical or practical domains. Both transitions fail since Kant can only stipulate, through reflecting judgement, how what is universal and necessary can be schematized in terms of the categories (either of understanding or of freedom) in order to systematize that which is particular and contingent (either empirical phenomena or individual moral commitments).
The failure of the transition in the practical philosophy is particularly disappointing. If successful, it would have shown how ‘agents determine the latitude of ethical duties and prioritize among them in cases of conflict’ (p. 163). How to resolve conflicts between ethical duties on Kantian grounds is one of the perennial problems of Kant scholarship and it would have been fantastic if OP shed new light on how these conflicts could be resolved. What light is shed, however, does not rely specifically on the analogy with the transition project in the OP, but rather with Kant’s scattered remarks in MM. These are brought together in such a way as to suggest that I resolve ethical conflicts by ‘reflecting on my web of maxims’ and ‘judging conscientiously’ on how the relationships I have to others would be affected by acting on one maxim rather than another (p. 215). Thorndike notes that Barbara Herman has already proposed such a ‘relationship sensitive’ account of moral obligation (cf. p. 215 n.). Going a step further, insofar as Kant relies on considered judgement to resolve conflicts between what would now seem to be conditional duties, it is unclear how Kant’s view (in this crucial practical respect) is all that different from W. D. Ross – a result that both philosophers would likely find surprising.
A lack of originality, however, is not itself a failure. The practical transition fails because it mirrors the theoretical transition which is also unsuccessful. According to Thorndike, the theoretical transition fails to connect the fundamental forces that constitute matter (attraction and repulsion) to the empirical phenomena they are intended to systematically explain (density, cohesion, elasticity and chemical forces) through the table of categories. As mentioned above, these connections ‘remain mere stipulations’ with the result that ‘Kant cannot inject the right kind of necessity into his mediating concepts of the Transition’ (p. 231). Likewise, the mediating concepts (moral feeling, conscience, love of human beings and respect for oneself) that one would presumably rely upon when making a considered judgement in the practical domain are not convincingly connected to the moral law through the categories of freedom.
Although these results are disappointing, they are not unexpected given the way Thorndike has set up his project. According to Thorndike, the mediating concepts of transition are the result of reflecting judgement although the metaphysical foundations (whether theoretical or practical) from which the transition sets off are delivered by determining judgement (p. 89). This creates an inherent problem of methodological coordination (reflecting vs. determining judgement). In fact, Michael Friedman has argued that this very problem constitutes the gap in Kant’s Critical philosophy (Friedman 1992: 254–6), a gap that Friedman likewise believes Kant fails to bridge in OP. Given the amount of time that Thorndike dedicates to discussing Friedman’s views, it is surprising that he does not dedicate any time to discussing this particular worry since it cuts to the very heart of his own approach. More troubling, however, is that there is scant textual evidence that Kant was at all concerned with the distinction between determining and reflecting judgement in OP, which poses a problem for Friedman and by extension for Thorndike. Another concern with Thorndike’s approach is one that he does recognize. Commentators dating back to Erich Adickes in the 1920s have noted that Kant’s attempt to connect empirical phenomena to the categories is ‘forced and arbitrary’ (cf. Thorndike, p. 110) and that Kant may well be chasing a ‘fata morgana’ in the early leaves of OP (p. 76). Insofar as the practical transition is structurally isomorphic with the theoretical transition in these early leaves, would it be surprising if Kant were chasing a practical fata morgana as well?
Even if Thorndike’s book fails to solve the problems it raises, it puts one in a position to see what problems scholars ought to tackle. I will suggest three lines of inquiry, though given the paucity of scholarship on OP, the options are almost limitless. The first is that more work should be done on the relationship between OP and Kant’s practical philosophy. Kant articulates a doctrine of practical self-positing in the later phases of OP (Convolut 7 from 1800) and at the end of the manuscript (Convolut 1 from 1800–3) also considers how God could connect both the theoretical and practical domains. Perhaps, these later leaves can offer additional clues as to how the practical gap Thorndike identifies could be bridged. Although scholars like Eckart Förster and Paul Guyer have written a modest amount on these themes (see, for instance, Förster 1993 and Guyer 2005), they warrant more ink being spilled on their behalf.
The second is that scholars should reassess whether the systematic perspective of Kant’s transition project stays the same or changes over time. Although Thorndike is generally careful to limit his claims concerning OP to the leaves written between 1796 and 1798, Kant’s perspective seems to change even in those leaves. Thorndike rightly notes that in the Octaventwurf section of OP, Kant is continuing a project that he started in the General Remark to the Dynamics in the Metaphysical Foundations of Natural Sciences, namely to show how specific empirical phenomena can be explained in terms of the metaphysics of matter (fundamental forces). Even though the ‘Octaventwurf’ label only rightly designates a small subset of the earliest leaves, Thorndike uses this label to refer to all of the leaves written from 1796–8, some of which pose problems for his interpretation. For example, in a passage that Thorndike quotes from Farrago 1 (p. 92), which Kant began in December of 1798, Kant holds that the gap is in ‘the pure science of nature’ (OP, 21: 640). This suggests that the gap lies not in a failure to apply metaphysical foundations to empirical phenomena (Thorndike’s view), but rather within the metaphysical foundations themselves.
Finally, scholars need to think more carefully about the interpretative principles they will use when approaching OP. I have said elsewhere that OP is like a philosophical Rorschach test (Hall 2015: 8). Given the structure of the manuscript – or lack thereof – it is easy for scholars to see what they want to see and usually they see quite different things. Thorndike should be praised for generally making clear that what he ‘sees’, i.e. his particular conception of the transition project, is limited to a certain phase in the development of the manuscript and does not necessarily reflect its final form (p. 225). Recognizing the developmental nature of the manuscript is a good principle of interpretation, one that Thorndike implicitly endorses though other scholars often ignore. Elsewhere, I suggest a few other principles that could be used to distinguish good interpretations from bad ones (Hall 2015: 5–6). One is particularly relevant to the present case: ceteris paribus, interpretations that fail to solve the philosophical problems they identify should be rejected in favour of interpretations that are philosophically coherent and fruitful. Although Thorndike’s interpretation of the practical transition holds that it fails to solve its intended philosophical problem, Kantians should hope that another interpretation is possible that solves this problem. Thorndike rightly notes that if we are unable to organize our moral commitments under the moral law, we will experience a loss of autonomy – moral agency – since our moral commitments will lose that connection with the moral law that rationally justifies them and renders them certain (pp. 178, 193). The stakes could not be higher for Kant and the failure of this transition project would leave a massive gap in the practical philosophy, one that we as moral agents once occupied.
