“Ueber die Eide”: Zucht und Kritik im Preussen der Aufklärung by Marcus Twellmann (review)

With a nod to Friedrich Nietzsche’s famous claim that cultural practices such as making a promise and the administering of punishment consist of ever-changing interpretations and legitimations, Marcus Twellmann embarks on his investigation of the vicissitudes to which the oath was subject in Prussia during the Enlightenment. The oath emerges in the course of Twellmann’s lucid argument, which is related in refreshingly crisp and precise prose, as a point of intersection between state administration, religious practice, and philosophical critique. Because the taking of an oath traditionally involved the invocation of the divine, its study allows Twellmann to treat the Enlightenment as an age as characterized as much by continuity as by rupture. Twellmann’s leading surmise is that the emergence of the modern state as a pastoral force, as interested in the spiritual salvation of its citizens as much as in the preservation of peace, preserved, albeit under shifting terms, the religious significance of oath taking. Tracing a breathtaking arc from public ordinances at the turn of the eighteenth century to the seminal philosophical reflections on oaths by Moses Mendelssohn and Immanuel Kant, and then closing with a poignant reflection on the fashionably controversial Carl Schmitt, Twellmann shows that the oath was a procedure by means of which the emerging state order compelled its subjects to speak the truth. The culminating moment in Twellmann’s march toward modernity is, undoubtedly, the treatment of oaths in the philosophy of Kant. For this Prussian philosopher, above all others, spearheaded a conception of the oath as a relationship between a human being and his or her conscience, thereby jettisoning the traditional role of God as guarantor of truth.

The first chapter of the study investigates an anecdote published in the Prussian Annalen der Gesetzgebung und der Gelehrsamkeit from 1789. This seemingly minor anecdote of a clergyman who refuses to take an oath allows Twellmann to show that the Prussian state at the end of the eighteenth century still employed the oath as an educational and disciplinary practice intertwined with moralizing ambitions. Whatever transformations to which the oath was submitted in the course of the Enlightenment, it becomes clear from the anecdote that a false oath was still submitted before a “figure of the third,” before an instance of the divine that putatively bears greater authority. The second chapter takes up the role of the oath within tractates on ceremony (Zeremonia lwissenschaft), which proliferated in the eighteenth century. The author shows with great analytic precision that ceremony bridged political and ecclesiastical discourses, and the ritualistic dimensions of oath taking were, in fact, highly contested throughout the eighteenth century. The chapter ultimately shows that Mendelssohn and Kant articulated vastly different understandings of the importance of ritual; the former embraced ceremony on the basis of its importance to lawful Jewish practice, whereas the latter dismissed it as an instance of the primitive fetish of external objects.

At the end of these two chapters Twellmann delves into the material that, ultimately, constitutes the study’s most impressive contribution: his investigation of the role of oaths in Kant’s philosophy. In a masterful synthesis of Kant’s mature philosophical writings, Twellmann shows the ramifications for the traditionally theological inflection of the oath, when Kant installs philosophy as the ultimate authority over the rightfulness of laws and conventions. Kant is a particularly fascinating object of inquiry for Twellmann, because the philosopher from Königsberg does not fully rob the oath of all validity, even after he has reduced traditional conceptions of the divine to mere “rhetorical fictions.” Twellmann demonstrates, contrary to the predominant opinion in the existing research, that Kant is not dismissive of prayer, ritual, and the oath, but that he treats them primarily in terms of their impact on the moral psychology of the subject.

In the subsequent two chapters, Twellmann turns his eye to Friedrich Nicolai’s Sebaldus Nothanker and Moses Mendelssohn’s reflections on oaths. The author addresses with great...