Martin Sticker’s Rationalizing (Vernünfteln) is an addition to Cambridge University Press’s ‘Elements’ series on the philosophy of Immanuel Kant. Like other elements in this series, Sticker’s piece is positioned as an intermediary in two senses. First, at roughly 70 pages, its length is between that of an article and a book. Second, and more importantly, Sticker’s piece serves as a synopsis of an existing trend in contemporary Kant scholarship while also providing a novel take on that trend. As the title makes clear, the existing scholarly trend Sticker focuses on is increasing attention in a series of articles and recent monographs to rationalization or self-deception in Kant’s moral theory. Sticker’s contribution to this burgeoning literature is invaluable. In what follows, I will first explain the role I see his book playing in Kant studies. I will then provide an overview of Sticker’s own account of rationalizing, ending with some comments on what’s likely the most distinctive and most controversial aspect of his account.

While interest in Kant’s account of self-deception and related issues of self-knowledge, self-conceit and moral opacity has been growing for some time – in the English literature we have, among others, Henry Allison (Reference Allison1990: 158–60), Jeanine Grenberg (Reference Grenberg and Denis2010) and Pablo Muchnik (Reference Muchnik, Muchnik and Anderson-Gold2010) to credit for this – it has accelerated in the past five or so years in particular. Much of this attention has come in the form of innovative articles focused on some particular facet of Kant’s theory of self-deception. Examples are: Anna Wehofsits’ recent account of the relation between the passions and self-deception (Wehofsits Reference Wehofsitsforthcoming), Jessica Tizzard’s piece on the distinction between moral weakness and self-deception (Tizzard Reference Tizzard2021), Anastasia Berg on moral opacity (Berg Reference Berg2020), and both Kate Moran and Francey Russell on self-conceit and its illusory character (Moran Reference Moran2014; Russell Reference Russell2020). In addition, some fairly recent monographs (my Papish Reference Papish2018 being an example) treat Kant’s theory of self-deception in meaningful detail while also branching out to nearby topics like Kant’s theory of evil and his account of self-cognition.

Sticker’s piece fills a gap this landscape has created. The aforementioned articles focus narrowly on some particular feature of self-deception and do not aim to provide a broader account of self-deception in Kant; they also do not account for Kant’s preferred emphasis on the concept of Vernünfteln in his practical philosophy. Sticker’s book does exactly that, while also keeping the attention strictly on Vernünfteln in a way that my book did not. In addition, Sticker aims to provide an account of Kantian rationalization that is different from my own in some key ways. I will note these shortly, but first it is necessary to give an overview of what Sticker’s view is and how he develops it.

Sticker argues that rationalizing is self-deception in relation to specifically moral matters (p. 6). While leaving it open that we can engage in self-deception in other areas as well – we can deceive ourselves about what’s in our self-interest, about our standing among our peers and perhaps more theoretical questions too – rationalizing in moral affairs is distinctive, at least for Kant, because it is driven by a rational interest in seeing oneself as morally justified (pp. 6, 29). Sticker also aims to show, in detail, how rationalizing works. More specifically, he discusses at length the sources of rationalization, the strategies used in rationalization and, most notably, the scope of rationalization.

With respect to its sources, in addition to the way that pure practical reason or our interest in being moral can fuel not only action from duty but also self-deception in cases where we fail to act well, Sticker highlights how common human reason, theoretical reason, and, most of all, empirical practical reason ‘enable and even motivate’ self-deception (p. 26). This account helps us appreciate the way that self-deception is not merely a failure of reason but simultaneously a perverted application of our rational faculties. Importantly, this account contains some helpful comments regarding how rationalizing relates to dialectic: while a ‘dialectical tension’ between duty and happiness is natural and unavoidable (p. 16), rationalizing is not similarly unavoidable (p. 50).

Concerning the strategies used in rationalization, Sticker differentiates between the different ways we can challenge either the purity or the strictness of the moral law. Purity, Sticker argues, is compromised when we introduce irrelevant criteria either into our moral assessments or our motives for action (p. 18), whereas strictness is violated when we advocate the idea that duty allows for exceptions (p. 19). As an especially interesting upshot of the way Sticker reconstructs this distinction, it turns out that impurity and laxity expose us to different sorts of moral hazards. In allowing irrelevant criteria, such as the requirement that an action satisfy inclination, to inform our moral deliberations or motives, we transform what was a pure moral principle into an impure one. This, Sticker notes, is especially dangerous, since impurity thus results in changes to our very conception of the principle of morality (p. 21). An agent can then see themselves as morally justified for all kinds of transgressions, so long as those transgressions are sanctioned by the criteria included into the now-impure moral principle. Strictness also has its dangers, even if these, since they do not damage our understanding of morality, seem a bit less alarming. Laxity involves a permissive attitude toward excusing oneself from the moral law, and so when strictness falls by the wayside, an agent’s sense of morality will remain intact but they will nonetheless feel emboldened to find excuses for their deviations (p. 22).

Finally, there is Sticker’s discussion of the scope of rationalization, which is the most novel – and probably the most controversial – element of the book. To the extent that there is a mainstream position regarding how extensively we can rationalize or self-deceive with respect to moral matters, that position puts a fairly narrow limit on self-deception. While we can rationalize with respect to what our maxims are in a given case, or what motive is determining us to act, it is often agreed that rationalization cannot go further than this without undermining Kant’s repeat claim that we always know, and that conscience continually alerts us to, what the moral law demands of us. While acknowledging this limit, Sticker also wants to argue that Kant’s notion of moral ‘corruption’ shows that rationalization can lead to a deeper and more ‘systematically distorted sense of right and wrong’ than has yet been recognized in the literature (p. 3). Given the cognitive pressure human beings are under to see themselves as morally justified in our actions, there is a meaningful risk that we will transform our episodic attempts to justify this or that particular wrongdoing into a more comprehensive sort of moral ‘ideology’, one that poses a significant threat to a proper conception of the moral law (pp. 38–9) For a compelling example, Sticker uses Kant’s own example of Christian Garve, whose eudaimonism is plausibly diagnosed as a more developed offshoot of rationalistic quibbling in favour of personal happiness (p. 41).

What will make this argument controversial is the question of whether Sticker can stay within the tight space to which Kant, and the norms of philosophical engagement with Kant, confine him. On the one hand, Sticker is right to want a more expansive account of rationalization than the one currently on offer in existing Kant scholarship. Anyone at all convinced, in ordinary life, of our talents for self-deception, as well as our ability to get so many things wrong in moral matters, will want to find as expansive an account of rationalization as possible in Kant. On the other hand, readers may wonder how far Sticker can really push a Kantian account of rationalization. As Sticker himself notes, rationalization against the moral law can never be ‘all-encompassing’ (p. 42). To quote: ‘An ideology is not adopted instead of the moral law, but as an addition’ or ‘modification’ (p. 42; Sticker’s emphasis). But does it make sense to think of Garve’s eudaimonism as an ‘addition’ to the categorical imperative? Or, consider another fascinating example from the very end of Sticker’s book, namely a moral ideology according to which our duty to be philanthropic is so demanding that we can lie, cheat and steal in the name of benevolence (p. 55). Such an extreme morality admittedly contains vestiges of a Kantian conception of duty insofar as it acknowledges the importance of helping others. But I am less confident than Sticker that this form of altruism would count as a distortion of morality that only ‘adds’ to our representation of the moral law. Nonetheless, Sticker’s challenge to Kantians to widen the scope of rationalization is a well-taken one that anyone writing on self-deception in Kant will have to wrestle with. And overall, his book is a first-rate philosophical work and an extremely important contribution to the field.