Karen Koch’s Denken in Zwecken is a masterful philosophical exploration of the issue of purposiveness (Zweckmässigkeit) in the theoretical philosophies of Kant and Hegel. Her book marks an important intervention in recent treatments of similar themes by scholars such as Thomas Khurana, Karen Ng, James Kreines, Hannah Ginsborg, Rachel Zuckert, and Ido Geiger. The philosophical problem that organizes the book is the existence of natural purposes. Is the description of organisms as purposive structures ontologically adequate? Or is it a category mistake to conceive of any natural entity as purposive? As Koch clarifies, how we answer the question has deep implications for our self-conception as thinking and acting beings. If we affirm the fundamental structure that nature does not involve purposes, then how do we understand ourselves, as ostensibly purposive beings, within such a framework?

Koch aims to defend a determinate perspective on purposiveness—one where purposes are crucial for our self-conception as subjects by examining and ultimately defending Hegel’s notion of purposiveness over Kant’s. As Koch argues, rather than being simply a better alternative, Hegel’s notion of purposiveness is a continuation of the project, which ends up offering a foundation for the Kantian conception. We cannot understand Hegel’s conception of purposiveness without Kant. But, while it is easy to show that Hegel considers his logical treatment of objectivity and the idea as solving difficulties of the Kantian conception, it is much harder to show that Hegel does indeed solve difficulties which are embedded in the Kantian conception.

Koch’s analysis does not disappoint in this respect. To summarize, she argues that Hegel shows objects to be individuated in terms of external purposiveness, and external purposiveness (and alongside judgements regarding teleological objects) to be grounded by inner purposiveness: without beings who are ends-in-themselves (understood not merely as analogies to artefacts, but as constitutively self-grounded) and who posit purposes based on their own impulses of self-maintenance and reproduction, there are no purposive objects such as tables and chairs. Furthermore, without teleological relations of external purposiveness (and, by implication, without inner purposiveness), there could not be even mechanical objects: teleology is the ‘truth’ of mechanism as mechanism is characterized by the indifference of its components to one another. This mechanical form of relation, as Koch claims Hegel shows, is too weak to supply the conditions for the individuation of anything. Insofar as Hegel’s arguments demonstrate that the individuality constitutive of objects (to which Kant grants reality) ultimately depends on inner purposiveness, it would be illegitimate not to grant a form of objective standing—actuality (Wirklichkeit)—to inner purposiveness. Although below I raise some concerns, I found Koch’s presentation of the argument insightful and plausible.

One of the most striking aspects of Koch’s work is her nuanced treatment of both Kant and Hegel. Whereas it is still not very common for Kant scholars to seriously engage with Hegel, Hegel-sympathizers often instrumentalize Kant for their own Hegelian purposes—either by taking Hegel’s criticisms of Kant as a ‘subjective idealist’ for granted to emphasize the distinctiveness of Hegel’s approach to philosophy, or by using Hegel’s intellectual proximity to Kant to grant Hegel’s philosophy a sense of stringency. None of this is by itself wrong, and much valuable scholarship has been produced through such instrumental contrast. After all, it is difficult to give both thinkers an equally nuanced consideration in a single work. Yet, nuanced treatment is precisely what Koch’s book achieves, and the reason why the book is equally valuable for Kant and Hegel scholars. Each chapter manages to mark a valuable intervention in some debate or another within the literature. The book is thus an apt example of what it means to interrogate historical figures with openness and curiosity regarding a philosophical problem, rather than using thinkers for the reconstruction or rationalization of a preferred position.

While contrasting the proposals of Kant and Hegel, Koch distances her reading of the Logic from those that she deems as ‘transcendental’ and ‘aprioristic’, such as Karen Ng’s and Robert Pippin’s. We ought not read the Logic as an examination the atemporal structures of thought, because such investigation presupposes a historical context and standpoint; the categories cannot be understood ‘a priori’ in the sense of being fixed forms in the human mind (cf. 272). But one might wonder if the disagreement here may not be merely terminological, and interpretations such as by Ng and Pippin might have a different understanding of the ‘a priori’ status of the Logic, perhaps one where it is to be equated with the Logic’s claim to purity, that it examines concepts ‘without sensuous substrata’ (GW 21:43 and SL transl. by Giovanni). And this possibility raises the question of how Koch understands Hegel’s claims of the Logic’s ‘purity’ as compatible with the historicity of thought-determinations.

I now turn to two critical questions for Koch’s reading of Kant and Hegel. Koch’s reading of Kant holds that both the systematic principle of reason and the principle of the purposiveness of nature are transcendental regulative principles. It is clear that Kant considers these principles to be necessary for empirical science, but the further claim that the principles of systematicity and purposiveness are transcendental is controversial in the literature. Koch’s argument for the transcendental status of the principles of reason rests on the fact that these are the conditions for empirical truth and empirical concepts. Due to Kant’s often conflicting uses of ‘experience’ and ‘transcendental’, I do not think a purely exegetical argument will suffice to settle the matter regarding the question of whether there is experience without empirical concepts and empirical truth. The philosophical dilemma faced by interpreters arguing for the transcendental status of such principles seems to be: either deflating our notion of ‘transcendental’ (such that X—in this case, the principles of reason—being a necessary condition for Y—in this case, empirical science, empirical truth) is sufficient to label X as ‘transcendental’, or we inflate our notion of experience such that it is always already an inferentially articulated whole that enables empirical concepts and empirical truth. Koch opts for this second version, which seems to signal she understands there is no possible experience without inferences and empirical concepts (81–82). Importantly, she denies such transcendental status to the principle of inner purposiveness, which suggests that her notion of ‘experience’ for Kant does not necessarily include organisms. But she also claims their transcendental status remains regulative, not constitutive of the objects of experience. These principles are a necessary condition for experience in that ‘without empirical concepts [there is no] empirical cognition’ (‘ohne empirische Begriffe keine empirische Erkenntnis)’ (82). Again, the question is: is empirical cognition a priori necessary for experience? Can we not conceive of experience without empirical cognition? I fear answering in the affirmative sets the bar for experience quite high. It makes sense to me that a non-systematic experience could still be experience, insofar as sensibility and the understanding a priori guarantee a minimal unity and capacity to form representations of objects.

I would have liked Koch to further defend her understanding of ‘experience’ for Kant, since that would have helped clarify her argument regarding the ‘transcendental’ status of the principles of reason.

Turning to a question for Koch’s insightful reading of Hegel, a core aim of Koch’s intervention, as outlined above, rests in her argument that shows how Hegel can account for purposiveness as possessing a certain ontological status which is more consistent than Kant’s ‘agnosticism’. Crucially, Hegel argues, according to Koch, that ‘in any sketch of actuality [Wirklichkeitsentwurf] where the actuality of inner purposiveness […] is denied, we ourselves as purposeful beings cannot occur in it at all’ (235). Hegel thus provides ‘a weighty argument against reductive naturalism and for the reality of inner purposiveness’ (235). If successful (which I think it is), Koch’s argument shows that if we understand ourselves as thinking and acting in accordance with purposes, then we must grant the actuality of inner purposiveness in nature. But an argument in the shape of a conditional is dangerous, as the argument’s force dissolves by a simple rejection of the antecedent. And indeed, many philosophers and philosophically-minded scientists do not seem to identify any great sacrifice in renouncing the existence of ‘the self’ as a purposive agent, or even the existence of objects. So, if the argument demonstrates that we require purposiveness to have ‘us’ qua ‘zwecktätige Wesen’ or individuated objects, a reductive naturalist could still say: ‘well, so much worse for “us” and the “objects.”’

A seemingly stronger point is that denying the actuality of purposiveness constitutes a ‘performative self-contradiction’ (204). One cannot claim to have a theory of reality that does not include purposive beings, since the very possibility of creating a theory of reality presupposes purposiveness. But one might reject the ‘performative contradiction’ argument as unconvincing. Many people do not believe entities such as ‘money’ or ‘gender’ fundamentally exist, and such rejection does not hinder them from still acting as if such entities existed. Further to the point, often acting as if such entities existed (say, asking one’s institution for research funds to fund a project about how money is illusory) is a condition of possibility of us creating theories about how those entities are not fundamental. I see nothing wrong or impossible there. Perhaps the argument is that purposiveness is different, for every action is predicated on its existence, so one could not even act as if believing purposiveness existed while claiming it does not, for the very capacity to act as such is already a purposive action—to which the purpose-denialist could reply: ‘fine, strictly speaking, I am not “acting”, I am moving under the illusion of action. Or better: there is something that moves under the illusion that it is acting as if it believed purpose existed.’ What would the Hegelian friend of purpose reply to this objection?

It is here, I believe, that the limitations of this conditional form of argument come to the fore. Unless we are willing to discount the testimony of many thinkers and claim all reductive naturalist metaphysical proposals are incoherent, reality and experience seem to be perfectly thinkable and explainable without having to grant the existence of purpose. Nothing forces us to theoretically accept the existence of intentions or actions or even individuated objects, if such acceptance conflicts with a deeper commitment to, say, the fundamentality of the physical. But I do not think this is a problem for Hegel. For, I think, Hegel thinks the truth of inner purposiveness (the truth of the idea, and with it the legitimacy of the form of absolute cognition Koch nicely outlines in chapter 8) does not rely on showing it to be the necessary condition for the constitution or explanation of experience or reality. Rather, Hegel is committed to the claim that the true validation of the categories would exhibit them as true ‘in and for themselves’, rather than presupposing a realm of validity that the categories must measure up to exhibit their worth and value (GW 21:35). If, as I hold, Hegel’s Logic is modelled after the requirement to examine the truth of categories ‘in and for themselves’, then a category’s truth would constitute an achievement of pure thought in its proper development, rather than it being something true because, were we not to accept its truth (actuality, objective standing), a presupposed reality would be unintelligible (unverständlich) or incomprehensible (unbegreiflich).

Of course, it is easy to nitpick, much harder would it be to propose an alternative account of exactly how Hegel demonstrates the truth of inner purposiveness independently of any presupposed commitments, such as the claim that we think and act in purposes—a claim which many contemporary thinkers do not seem to regard as a great sacrifice for the sake of consistent metaphysical naturalism. And Koch’s book sets the bar for any alternative proposal quite high. There is much more to Koch’s important book that merits discussion. The work is an excellent piece of scholarship, forcefully defending many original insights with an exceptional mastery of the primary texts, the secondary literature, and the contemporary debates going well beyond Kant and Hegel. The book is a concrete example of a work that exhibits the value of historical thinkers for philosophical problems that are very much alive today. Anyone interested in Kant, Hegel, or the philosophical problems surrounding teleology and purposiveness will greatly benefit from reading Karen Koch’s book.