[3] It was published in 1785: _The Kritik der Reinen Vernunft,_ first edition, in 1781.--(_Translator_.)
[4] His analysis is really derived from myself, but in this place I am speaking incognito.
ON THE IMPERATIVE FORM OF THE KANTIAN ETHICS.
Kant's _πρῶτον ψεῡδος_ (first false step) lies in his conception of Ethics itself, and this is found very clearly expressed on page 62 (R., p. 54): "In a system of practical philosophy we are not concerned with adducing reasons for that which takes place, but with formulating laws regarding that which =ought to take place, even if it never does take place=." This is at once a distinct _petitio principii._ Who tells you that there are laws to which our conduct =ought= to be subject? Who tells you that that =ought to take place, which in fact never does take place=? What justification have you for making this assumption at the outset, and consequently for forcing upon us, as the only possible one, a system of Ethics couched in the imperative terms of legislation? I say, in contradistinction to Kant, that the student of Ethics, and no less the philosopher in general, must content himself with explaining and interpreting that which is given, in other words, that which really is, or takes place, so as to obtain an =understanding= of it, and I maintain furthermore that there is plenty to do in this direction, much more than has hitherto been done, after the lapse of thousands of years. Following the above _petitio principii_, Kant straightway, without any previous investigation, assumes in the preface (which is entirely devoted to the subject), that purely moral laws exist; and this assumption remains thenceforth undisturbed, and forms the very foundation of his whole system. We, however, prefer first of all to examine the conception denoted by the word "law." The true and original meaning of the term is limited to law as between citizens; it is the _lex_, _νόμος_, of the Romans and Greeks, a human institution, and depending on human volition. It has a secondary, derived, figurative, metaphorical meaning, when applied to Nature, whose operations, partly known _a priori_, partly learnt by experience, and which are always constant, we call natural laws. Only a very small portion of these natural laws can be discerned _a priori_, and with admirable acuteness, Kant set them apart, and classed them under the name "Metaphysics of Nature." There is also undoubtedly a law for the human will, in so far as man belongs to Nature; and this law is strictly provable, admits of no exception, is inviolable, and immovable as the mountains, and does not, like the Categorical Imperative, imply a quasi-necessity, but rather a complete and absolute one. It is the law of motivation, a form of the law of causation; in other words, it is the causation which is brought about by the medium of the understanding. It is the sole demonstrable law to which the human will =as such= is subject. It means that every action can only take place in consequence of a sufficient motive. Like causality in general, it is a natural law. On the other hand, moral laws, apart from human institution, state ordinance, or religious doctrine, cannot rightly be assumed as existing without proof. Kant, therefore, by taking such laws for granted, is guilty of a _petitio principii_, which is all the bolder, in that he at once adds (page vi of the preface) that a moral law ought to imply "=absolute necessity=." But "absolute necessity" is everywhere characterised by an inevitable chain of consequence; how, then, can such a conception be attached to these alleged moral laws (as an instance of which he adduces "thou shalt not lie"[1])? Every one knows, and he himself admits, that no such consecution for the most part takes place; the reverse, indeed, is the rule.