of causality as freedom with causality as rational mechanism, the former established by the moral law, the latter by the law of nature in the same subject, namely, man, is impossible, unless we conceive him with reference to the former as a being in himself, and with reference to the latter as a phenomenon- the former in pure consciousness, the latter in empirical consciousness. Otherwise reason inevitably contradicts itself.
3
A reviewer who wanted to find some fault with this work has hit the truth better, perhaps, than he thought, when he says that no new principle of morality is set forth in it, but only a new formula. But who would think of introducing a new principle of all morality and making himself as it were the first discoverer of it, just as if all the world before him were ignorant what duty was or had been in thorough-going error? But whoever knows of what importance to a mathematician a formula is, which defines accurately what is to be done to work a problem, will not think that a formula is insignificant and useless which does the same for all duty in general.
4
[See Kant's "Das mag in der Theoric ricktig seyn," etc. Werke, vol. vii, p. 182.]
5
(2) It might also have been objected to me that I have not first defined the notion of the faculty of desire, or of the feeling of Pleasure, although this reproach would be unfair, because this definition might reasonably be presupposed as given in psychology. However, the definition there given might be such as to found the determination of the faculty of desire on the feeling of pleasure (as is commonly done), and thus the supreme principle of practical philosophy would be necessarily made empirical, which, however, remains to be proved and in this critique is altogether refuted. It will, therefore, give this definition here in such a manner as it ought to be given, in order to leave this contested point open at the beginning, as it should be. LIFE is the faculty a being has of acting according to laws of the faculty of desire. The faculty of DESIRE is the being's faculty of becoming by means of its ideas the cause of the actual existence of the objects of these ideas. PLEASURE is the idea of the agreement of the object, or the action with the subjective conditions of life, i.e., with the faculty of causality of an idea in respect of the actuality of its object (or with the determination of the forces of the subject to action which produces it). I have no further need for the purposes of this critique of notions borrowed from psychology; the critique itself supplies the rest. It is easily seen that the question whether the faculty of desire is always based on pleasure, or whether under certain conditions pleasure only follows the determination of desire, is by this definition left undecided, for it is composed only of terms belonging to the pure understanding, i.e., of categories which contain nothing empirical. Such precaution is very desirable in all philosophy and yet is often neglected; namely, not to prejudge questions by adventuring definitions before the notion has been completely analysed, which is often very late. It may be observed through the whole course of the critical philosophy (of the theoretical as well as the practical reason) that frequent opportunity offers of supplying defects in the old dogmatic method of philosophy, and of correcting errors which are not observed until we make such rational use of these notions viewing them as a whole.
6
I am more afraid in the present treatise of occasional misconception in respect of some expressions which I have chosen with the greatest care in order that the notion to which they point may not be missed. Thus, in the table of categories of the Practical reason under the title of Modality, the Permitted, and forbidden (in a practical objective point of view, possible and impossible) have almost the same meaning in common language as the next category, duty and contrary to duty. Here, however, the former means what coincides with, or contradicts, a merely possible practical precept (for example, the solution of all problems of geometry and mechanics); the latter, what is similarly related to a law actually present in the reason; and this distinction is not quite foreign even to common language, although somewhat unusual. For example, it is forbidden to an orator, as such, to forge new words or constructions; in a certain degree this is permitted to a poet; in neither case is there any question of duty. For if anyone chooses to forfeit his reputation as an orator, no one can prevent him. We have here only to do with the distinction of imperatives into problematical, assertorial, and apodeictic. Similarly in the note in which I have pared the moral ideas of practical perfection in different philosophical schools, I have distinguished the idea of wisdom from that of holiness, although I have stated that essentially and objectively they are the same. But in that place I understand by the former only that wisdom to which man (the Stoic) lays claim; therefore I take it subjectively as an attribute alleged to belong to man. (Perhaps the expression virtue, with which also the Stoic made great show, would better mark the characteristic of his school.) The expression of a postulate of pure practical reason might give most occasion to misapprehension in case the reader confounded it with the signification of the postulates in pure mathematics, which carry apodeictic certainty with them. These, however, postulate the possibility of an action, the object of which has been previously recognized a priori in theory as possible, and that with perfect certainty. But the former postulates the possibility of an object itself (God and the immortality of the soul) from apodeictic practical laws, and therefore only for the purposes of a practical reason. This certainty of the postulated possibility then is not at all theoretic, and consequently not apodeictic; that is to say, it is not a known necessity as regards the object, but a necessary supposition as regards the subject, necessary for the obedience to its objective but practical laws. It is, therefore, merely a necessary hypothesis. I could find no better expression for this rational necessity, which is subjective, but yet true and unconditional.
7
Names that designate the followers of a sect have always been accompanied with much injustice; just as if one said, "N is an Idealist." For although he not only admits, but even insists, that our ideas of external things have actual objects of external things corresponding to them, yet he holds that the form of the intuition does not depend on them but on the human mind.
8
Propositions which in mathematics or physics are called practical ought properly to be called technical. For they have nothing to do with the determination of the will; they only point out how a certain effect is to be produced and are, therefore, just as theoretical as any propositions which express the connection of a cause with an effect. Now whoever chooses the effect must also choose the cause.
