Are Kant's First Two Moral Principles Equivalent? JOHN E. ATWELL "AcT m SUCHA WAY that you always treat humanity, whether in your own person or in the person of any other, never merely as a means, but always at the same time as an end." 1 By referring to this moral principle (hereafter, the principle of personality ) as the se~:ond formula of the moral law, Kant suggests the view, later made explicit, that it is in some sense equivalent with the first formula, that is, the principle of universality (or the categorical imperative): "Act only on that maxim through which you can at the same time will that it should become a universal law." 2 Writers on Kant's moral theory disagree, notoriously, on many points of interpretation and criticism, but most of them agree in objecting to the claim that the two aforementioned principles are equivalent, s (I am leaving out of consideration the third principle, as well as variations on the first and second.) In the main, however, these critics fail to support fully their objection, for they neither examine closely the second principle nor explain what it means (in general or for Kant) for two moral principles to be equivalent or nonequivalent. I intend to do both, in hopes of determining whether or not the objection is valid. First, however, a qualification. I shall interpret the principle of personality as if it read: "Act in such a way that you always treat other persons never merely as means, but always at the same time as ends." There are two main reasons for this reformulation. First, it allows me to ignore the question of what Kant meant by the phrase "treat humanity." This is a troublesome notion even when supplemented by "in your own person or in the person of any other," and since: it tends to obscure an already "dark saying" (Carritt's expression) without adding anything that "'person" cannot be construed to signify, I shall omit it. Secondly, the reformulation serves to exclude from consideration so-called "duties to oneself." I doubt that there are any such duties (unless "duties" in "duties to oneself" is understood as For discussing with me the contents of this paper I am especially indebted to my former colleague, Donald E. Salter, and my wife. Grundlegung zur Metaphysik tier Sitten, Academy eel., IV, 429. I am using, with occasional alteration, the translation by H. ]. Paton, The Moral Law (London: Hutchinson Univ. Library, 1948). Hereafter, references to the Grundlegung axe cited as "Gr" followed by the Academy ed. page number in IV. = Gr, 421. = Kant doesn't use the term "equivalent," but he does say, referring to the three main principles, "The aforesaid three ways of r~presenting the principle of morality axe at bottom so many formulations of precisely the same law... (Gr, 436). That most critics do object to this contention needs no citation. [273] 274 HISTORY OF PHILOSOPHY having quite a different meaning than it has in "duties to others"). But if there are, they do not fall within the province of the principle to be dealt with here. Besides, it is not at all clear how one could possibly violate a duty to oneself when this means, as here it must, treating oneself merely as a means. In order to determine whether two moral principles are equivalent or not, we must first come to some understanding as to what a moral principle is. I emphasize "some" because I am not prepared to state the nature of a moral principle (if there is one), nor do I see any need to try. It is sufficient for my purposes to say something in general about the task of a moral principle, about the setting in which it is used, about the primary user, and so on. Because one might claim that two principles are not equivalent when actually they were simply employed differently, this discussion is at the same time indispensable. Speaking generally now, a moral principle is meant to be (or to provide), in varying degrees of specificity, a moral criterion, that is, a criterion for deciding what one ought and ought not to do. When faced...