More refined, though equally false, is the theory of those who suppose a certain special moral sense, which sense and not reason determines the moral law, and in consequence of which the consciousness of virtue is supposed to be directly connected with contentment and pleasure; that of vice, with mental dissatisfaction and pain; thus reducing the whole to the desire of private happiness. Without repeating what has been said above, I will here only remark the fallacy they fall into. In order to imagine the vicious man as tormented with mental dissatisfaction by the consciousness of his transgressions, they must first represent him as in the main basis of his character, at least in some degree, morally good; just as he who is pleased with the consciousness of right conduct must be conceived as already virtuous. The notion of morality and duty must, therefore, have preceded any regard to this satisfaction, and cannot be derived from it. A man must first appreciate the importance of what we call duty, the authority of the moral law, and the immediate dignity which the following of it gives to the person in his own eyes, in order to feel that satisfaction in the consciousness of his conformity to it and the bitter remorse that accompanies the consciousness of its transgression. It is, therefore, impossible to feel this satisfaction or dissatisfaction prior to the knowledge of obligation, or to make it the basis of the latter. A man must be at least half honest in order even to be able to form a conception of these feelings. I do not deny that as the human will is, by virtue of liberty, capable of being immediately determined by the moral law, so frequent practice in accordance with this principle of determination can, at least, produce subjectively a feeling of satisfaction; on the contrary, it is a duty to establish and to cultivate this, which alone deserves to be called properly the moral feeling; but the notion of duty cannot be derived from it, else we should have to suppose a feeling for the law as such, and thus make that an object of sensation which can only be thought by the reason; and this, if it is not to be a flat contradiction, would destroy all notion of duty and put in its place a mere mechanical play of refined inclinations sometimes contending with the coarser.

If now we compare our formal supreme principle of pure practical reason (that of autonomy of the will) with all previous material principles of morality, we can exhibit them all in a table in which all possible cases are exhausted, except the one formal principle; and thus we can show visibly that it is vain to look for any other principle than that now proposed. In fact all possible principles of determination of the will are either merely subjective, and therefore empirical, or are also objective and rational; and both are either external or internal.

Practical Material Principles of Determination taken as the Foundation of Morality, are:

{BOOK_1|CHAPTER_1 ^paragraph 105}

SUBJECTIVE

EXTERNAL INTERNAL

Education Physical feeling

{BOOK_1|CHAPTER_1 ^paragraph 110}

(Montaigne) (Epicurus)

The civil Moral feeling

Constitution (Hutcheson)

(Mandeville)

{BOOK_1|CHAPTER_1 ^paragraph 115}

OBJECTIVE

INTERNAL EXTERNAL

Perfection Will of God

(Wolf and the (Crusius and other {BOOK_1|CHAPTER_1 ^paragraph 120} Stoics) theological Moralists)

Those of the upper table are all empirical and evidently incapable of furnishing the universal principle of morality; but those in the lower table are based on reason (for perfection as a quality of things, and the highest perfection conceived as substance, that is, God, can only be thought by means of rational concepts). But the former notion, namely, that of perfection, may either be taken in a theoretic signification, and then it means nothing but the completeness of each thing in its own kind (transcendental), or that of a thing merely as a thing (metaphysical); and with that we are not concerned here. But the notion of perfection in a practical sense is the fitness or sufficiency of a thing for all sorts of purposes. This perfection, as a quality of man and consequently internal, is nothing but talent and, what strengthens or completes this, skill. Supreme perfection conceived as substance, that is God, and consequently external (considered practically), is the sufficiency of this being for all ends. Ends then must first be given, relatively to which only can the notion of perfection (whether internal in ourselves or external in God) be the determining principle of the will. But an end- being an object which must precede the determination of the will by a practical rule and contain the ground of the possibility of this determination, and therefore contain also the matter of the will, taken as its determining principle- such an end is always empirical and, therefore, may serve for the Epicurean principle of the happiness theory, but not for the pure rational principle of morality and duty. Thus, talents and the improvement of them, because they contribute to the advantages of life; or the will of God, if agreement with it be taken as the object of the will, without any antecedent independent practical principle, can be motives only by reason of the happiness expected therefrom. Hence it follows, first, that all the principles here stated are material; secondly, that they include all possible material principles; and, finally, the conclusion, that since material principles are quite incapable of furnishing the supreme moral law (as has been shown), the formal practical principle of the pure reason (according to which the mere form of a universal legislation must constitute the supreme and immediate determining principle of the will) is the only one possible which is adequate to furnish categorical imperatives, that is, practical laws (which make actions a duty), and in general to serve as the principle of morality, both in criticizing conduct and also in its application to the human will to determine it.

I. Of the Deduction of the Fundamental Principles of Pure Practical Reason.

{BOOK_1|CHAPTER_1 ^paragraph 125}

This Analytic shows that pure reason can be practical, that is, can of itself determine the will independently of anything empirical; and this it proves by a fact in which pure reason in us proves itself actually practical, namely, the autonomy shown in the fundamental principle of morality, by which reason determines the will to action.

It shows at the same time that this fact is inseparably connected with the consciousness of freedom of the will, nay, is identical with it; and by this the will of a rational being, although as belonging to the world of sense it recognizes itself as necessarily subject to the laws of causality like other efficient causes; yet, at the same time, on another side, namely, as a being in itself, is conscious of existing in and being determined by an intelligible order of things; conscious not by virtue of a special intuition of itself, but by virtue of certain dynamical laws which determine its causality in the sensible world; for it has been elsewhere proved that if freedom is predicated of us, it transports us into an intelligible order of things.

Now, if we compare with this the analytical part of the critique of pure speculative reason, we shall see a remarkable contrast. There it was not fundamental principles, but pure, sensible intuition (space and time), that was the first datum that made a priori knowledge possible, though only of objects of the senses. Synthetical principles could not be derived from mere concepts without intuition; on the contrary, they could only exist with reference to this intuition, and therefore to objects of possible experience, since it is the concepts of the understanding, united with this intuition, which alone make that knowledge possible which we call experience. Beyond objects of experience, and therefore with regard to things as noumena, all positive knowledge was rightly disclaimed for speculative reason. This reason, however, went so far as to establish with certainty the concept of noumena; that is, the possibility, nay, the necessity, of thinking them; for example, it showed against all objections that the supposition of freedom, negatively considered, was quite consistent with those principles and limitations of pure theoretic reason. But it could not give us any definite enlargement of our knowledge with respect to such objects, but, on the contrary, cut off all view of them altogether.

On the other hand, the moral law, although it gives no view, yet gives us a fact absolutely inexplicable from any data of the sensible world, and the whole compass of our theoretical use of reason, a fact which points to a pure world of the understanding, nay, even defines it positively and enables us to know something of it, namely, a law.

{BOOK_1|CHAPTER_1 ^paragraph 130}

This law (as far as rational beings are concerned) gives to the world of sense, which is a sensible system of nature, the form of a world of the understanding, that is, of a supersensible system of nature, without interfering with its mechanism. Now, a system of nature, in the most general sense, is the existence of things under laws. The sensible nature of rational beings in general is their existence under laws empirically conditioned, which, from the point of view of reason, is heteronomy. The supersensible nature of the same beings, on the other hand, is their existence according to laws which are independent of every empirical condition and, therefore, belong to the autonomy of pure reason. And, since the laws by which the existence of things depends on cognition are practical, supersensible nature, so far as we can form any notion of it, is nothing else than a system of nature under the autonomy of pure practical reason. Now, the law of this autonomy is the moral law, which, therefore, is the fundamental law of a supersensible nature, and of a pure world of understanding, whose counterpart must exist in the world of sense, but without interfering with its laws. We might call the former the archetypal world (natura archetypa), which we only know in the reason; and the latter the ectypal world (natura ectypa), because it contains the possible effect of the idea of the former which is the determining principle of the will. For the moral law, in fact, transfers us ideally into a system in which pure reason, if it were accompanied with adequate physical power, would produce the summum bonum, and it determines our will to give the sensible world the form of a system of rational beings.

The least attention to oneself proves that this idea really serves as the model for the determinations of our will.

When the maxim which I am disposed to follow in giving testimony is tested by the practical reason, I always consider what it would be if it were to hold as a universal law of nature. It is manifest that in this view it would oblige everyone to speak the truth. For it cannot hold as a universal law of nature that statements should be allowed to have the force of proof and yet to be purposely untrue. Similarly, the maxim which I adopt with respect to disposing freely of my life is at once determined, when I ask myself what it should be, in order that a system, of which it is the law, should maintain itself. It is obvious that in such a system no one could arbitrarily put an end to his own life, for such an arrangement would not be a permanent order of things. And so in all similar cases. Now, in nature, as it actually is an object of experience, the free will is not of itself determined to maxims which could of themselves be the foundation of a natural system of universal laws, or which could even be adapted to a system so constituted; on the contrary, its maxims are private inclinations which constitute, indeed, a natural whole in conformity with pathological (physical) laws, but could not form part of a system of nature, which would only be possible through our will acting in accordance with pure practical laws. Yet we are, through reason, conscious of a law to which all our maxims are subject, as though a natural order must be originated from our will. This law, therefore, must be the idea of a natural system not given in experience, and yet possible through freedom; a system, therefore, which is supersensible, and to which we give objective reality, at least in a practical point of view, since we look on it as an object of our will as pure rational beings.

Hence the distinction between the laws of a natural system to which the will is subject, and of a natural system which is subject to a will (as far as its relation to its free actions is concerned), rests on this, that in the former the objects must be causes of the ideas which determine the will; whereas in the latter the will is the cause of the objects; so that its causality has its determining principle solely in the pure faculty of reason, which may therefore be called a pure practical reason.

There are therefore two very distinct problems: how, on the one side, pure reason can cognise objects a priori, and how on the other side it can be an immediate determining principle of the will, that is, of the causality of the rational being with respect to the reality of objects (through the mere thought of the universal validity of its own maxims as laws).

{BOOK_1|CHAPTER_1 ^paragraph 135}

The former, which belongs to the critique of the pure speculative reason, requires a previous explanation, how intuitions without which no object can be given, and, therefore, none known synthetically, are possible a priori; and its solution turns out to be that these are all only sensible and, therefore, do not render possible any speculative knowledge which goes further than possible experience reaches; and that therefore all the principles of that pure speculative reason avail only to make experience possible; either experience of given objects or of those that may be given ad infinitum, but never are completely given.

The latter, which belongs to the critique of practical reason, requires no explanation how the objects of the faculty of desire are possible, for that being a problem of the theoretical knowledge of nature is left to the critique of the speculative reason, but only how reason can determine the maxims of the will; whether this takes place only by means of empirical ideas as principles of determination, or whether pure reason can be practical and be the law of a possible order of nature, which is not empirically knowable. The possibility of such a supersensible system of nature, the conception of which can also be the ground of its reality through our own free will, does not require any a priori intuition (of an intelligible world) which, being in this case supersensible, would be impossible for us. For the question is only as to the determining principle of volition in its maxims, namely, whether it is empirical, or is a conception of the pure reason (having the legal character belonging to it in general), and how it can be the latter. It is left to the theoretic principles of reason to decide whether the causality of the will suffices for the realization of the objects or not, this being an inquiry into the possibility of the objects of the volition. Intuition of these objects is therefore of no importance to the practical problem. We are here concerned only with the determination of the will and the determining principles of its maxims as a free will, not at all with the result. For, provided only that the will conforms to the law of pure reason, then let its power in execution be what it may, whether according to these maxims of legislation of a possible system of nature any such system really results or not, this is no concern of the critique, which only inquires whether, and in what way, pure reason can be practical, that is directly determine the will.