Yvonne Unna

: The article provides an introduction to an autograph draft of a letter on dietetics Kant wrote to the physician Christoph Wilhelm Hufeland and uses it as a springboard for the critical discussion of Kant’s dietetics as well as its systematic place in his philosophy. The final draft of Kant’s letter to Hufeland became the third part of The Conflict of the Faculties. The article argues that Kant assigns dietetics, understood as the regulation of the traditional nonnaturals, to philosophy and not to medicine; that he regards moral health as the basis for physical health; and that his view of the systematic place of dietetics in his philosophy is inconsistent.

The goal of this dissertation is two-fold. It is, first, to reconstruct Kant's argument against self-murder, and, second, to analyze the function of the principle of self-preservation of reason with regard to the prohibition of self-murder. I argue that self-murder is contrary to the principle of self-preservation of reason and violates the trustee-relationship between the homo phaenomenon and the homo noumenon. The analysis shows that moral self-preservation in Kant is a rational principle which serves to secure the possibility of moral faith and self-perfection. ;In the first part of the dissertation, I provide a comprehensive analysis of Kant's argument against self-murder by examining all of the relevant statements in his works, the Nachlass, as well as the lectures recorded by Herder, Powalski, Collins, and Vigilantius. Since self-murder violates a perfect duty to oneself, key-topics of the analysis are: the dual status of the duty of self-preservation as both inner duty of right and duty of virtue, the right and end of humanity, as well as Kant's model of self-possession in terms of proprietas. The analysis makes clear that self-murder destroys the moral self and must be distinguished from sacrificing one's life in order to preserve one's moral integrity. ;In the second part of the dissertation, I interpret the duty of self-preservation and the prohibition of self-murder in the context of Kant's doctrine of the faith of reason and the principle of self-preservation of reason. I first provide an overview of the debate on self-preservation and its implications for an understanding of modern rationality and summarize the different meanings of -preservation in Kant. I then argue that the "principle of self-preservation of reason" consists in what Kant calls "the maxim of healthy reason" and that it grounds the faith and the unity of reason. Against the background of this analysis, I interpret the trustee-relationship between the homo phaenomenon and the homo noumenon as a model of moral self-obligation. Entrusting the homo phaenomenon to the homo noumenon, I contend, means to entrust life to practical reason and to subject oneself to the moral law