No More Learning

The Critique of Practical Reason
The Metaphysical Elements of Ethics
and
Fundamental Principles of the Metaphysic of Morals
by
Immanuel Kant Translation by Thomas Kingsmill Abbott
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Contents
THE CRITIQUE OF PRACTICAL REASON . . . . . . . . . . . . . . . . . . . . . . . . 4 THE METAPHYSICAL ELEMENTS OF ETHICS . . . . . . . . . . . . 165
FUNDAMENTAL PRINCIPLES OF THE METAPHYSIC OF MORALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202
Immanuel Kant
3
The Critique of Practical Reason
THE CRITIQUE
OF PRACTICAL
REASON
by
Immanuel Kant
translated by Thomas Kingsmill Abbott 1788
PREFACE
THIS WORK IS CALLED the Critique of Practical Reason, not of the pure practical reason, although its parallelism with the speculative critique would seem to require the latter term. The reason of this appears sufficiently from the treatise itself. Its business is to show that there is pure practical reason, and for this purpose it criticizes the entire practical faculty of reason. If it succeeds in this, it has no
4
need to criticize the pure faculty itself in order to see whether reason in making such a claim does not presumptuously overstep itself (as is the case with the speculative reason). For if, as pure reason, it is actually practical, it proves its own reality and that of its concepts by fact, and all disputation against the possibility of its being real is futile.
With this faculty, transcendental freedom is also established; free- dom, namely, in that absolute sense in which speculative reason required it in its use of the concept of causality in order to escape the antinomy into which it inevitably falls, when in the chain of cause and effect it tries to think the unconditioned. Speculative rea- son could only exhibit this concept (of freedom) problematically as not impossible to thought, without assuring it any objective reality, and merely lest the supposed impossibility of what it must at least allow to be thinkable should endanger its very being and plunge it into an abyss of scepticism.
Inasmuch as the reality of the concept of freedom is proved by an apodeictic law of practical reason, it is the keystone of the whole system of pure reason, even the speculative, and all other concepts (those of God and immortality) which, as being mere ideas, remain in it unsupported, now attach themselves to this concept, and by it obtain consistence and objective reality; that is to say, their possibil- ity is proved by the fact that freedom actually exists, for this idea is revealed by the moral law.
Freedom, however, is the only one of all the ideas of the specula- tive reason of which we know the possibility a priori (without, how- ever, understanding it), because it is the condition of the moral law which we know. * The ideas of God and immortality, however, are
* Lest any one should imagine that he finds an inconsistency here when I call freedom the condition of the moral law, and hereafter maintain in the treatise itself that the moral law is the condition under which we can first become conscious of freedom, I will merely remark that freedom is the ratio essendi of the moral law, while the moral law is the ratio cognoscendi of freedom. For Pad not the moral law been previously distinctly thought in our reason, we should never consider ourselves justified in assuming such a thing as freedom, although it be not contradictory. But were there no free- dom it would be impossible to trace the moral law in ourselves at all.
Immanuel Kant
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The Critique of Practical Reason
not conditions of the moral law, but only conditions of the neces- sary object of a will determined by this law; that is to say, conditions of the practical use of our pure reason. Hence, with respect to these ideas, we cannot affirm that we know and understand, I will not say the actuality, but even the possibility of them. However they are the conditions of the application of the morally determined will to its object, which is given to it a priori, viz. , the summum bonum. Con- sequently in this practical point of view their possibility must be assumed, although we cannot theoretically know and understand it. To justify this assumption it is sufficient, in a practical point of view, that they contain no intrinsic impossibility (contradiction). Here we have what, as far as speculative reason is concerned, is a merely subjective principle of assent, which, however, is objectively valid for a reason equally pure but practical, and this principle, by means of the concept of freedom, assures objective reality and au- thority to the ideas of God and immortality. Nay, there is a subjec- tive necessity (a need of pure reason) to assume them. Nevertheless the theoretical knowledge of reason is not hereby enlarged, but only the possibility is given, which heretofore was merely a problem and now becomes assertion, and thus the practical use of reason is con- nected with the elements of theoretical reason. And this need is not a merely hypothetical one for the arbitrary purposes of speculation, that we must assume something if we wish in speculation to carry reason to its utmost limits, but it is a need which has the force of law to assume something without which that cannot be which we must inevitably set before us as the aim of our action.
It would certainly be more satisfactory to our speculative reason if it could solve these problems for itself without this circuit and pre- serve the solution for practical use as a thing to be referred to, but in fact our faculty of speculation is not so well provided. Those who boast of such high knowledge ought not to keep it back, but to exhibit it publicly that it may be tested and appreciated. They want to prove: very good, let them prove; and the critical philosophy lays its arms at their feet as the victors. Quid statis? Nolint. Atqui licet esse beatis. As they then do not in fact choose to do so, probably because they cannot, we must take up these arms again in order to seek in the mortal use of reason, and to base on this, the notions of
6
God, freedom, and immortality, the possibility of which specula- tion cannot adequately prove.
Here first is explained the enigma of the critical philosophy, viz. : how we deny objective reality to the supersensible use of the catego- ries in speculation and yet admit this reality with respect to the ob- jects of pure practical reason. This must at first seem inconsistent as long as this practical use is only nominally known. But when, by a thorough analysis of it, one becomes aware that the reality spoken of does not imply any theoretical determination of the categories and extension of our knowledge to the supersensible; but that what is meant is that in this respect an object belongs to them, because either they are contained in the necessary determination of the will a priori, or are inseparably connected with its object; then this inconsistency disappears, because the use we make of these concepts is different from what speculative reason requires. On the other hand, there now appears an unexpected and very satisfactory proof of the consistency of the speculative critical philosophy. For whereas it insisted that the objects of experience as such, including our own subject, have only the value of phenomena, while at the same time things in themselves must be supposed as their basis, so that not everything supersensible was to be regarded as a fiction and its concept as empty; so now prac- tical reason itself, without any concert with the speculative, assures reality to a supersensible object of the category of causality, viz. , free- dom, although (as becomes a practical concept) only for practical use; and this establishes on the evidence of a fact that which in the former case could only be conceived. By this the strange but certain doctrine of the speculative critical philosophy, that the thinking subject is to itself in internal intuition only a phenomenon, obtains in the critical examination of the practical reason its full confirmation, and that so thoroughly that we should be compelled to adopt this doctrine, even if the former had never proved it at all. *
* The union 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.
Immanuel Kant
? 7
The Critique of Practical Reason
By this also I can understand why the most considerable objec- tions which I have as yet met with against the Critique turn about these two points, namely, on the one side, the objective reality of the categories as applied to noumena, which is in the theoretical department of knowledge denied, in the practical affirmed; and on the other side, the paradoxical demand to regard oneself qua subject of freedom as a noumenon, and at the same time from the point of view of physical nature as a phenomenon in one's own empirical consciousness; for as long as one has formed no definite notions of morality and freedom, one could not conjecture on the one side what was intended to be the noumenon, the basis of the alleged phenomenon, and on the other side it seemed doubtful whether it was at all possible to form any notion of it, seeing that we had pre- viously assigned all the notions of the pure understanding in its theoretical use exclusively to phenomena. Nothing but a detailed criticism of the practical reason can remove all this misapprehen- sion and set in a clear light the consistency which constitutes its greatest merit.
So much by way of justification of the proceeding by which, in this work, the notions and principles of pure speculative reason which have already undergone their special critical examination are, now and then, again subjected to examination. This would not in other cases be in accordance with the systematic process by which a sci- ence is established, since matters which have been decided ought only to be cited and not again discussed. In this case, however, it was not only allowable but necessary, because reason is here consid- ered in transition to a different use of these concepts from what it had made of them before. Such a transition necessitates a compari- son of the old and the new usage, in order to distinguish well the new path from the old one and, at the same time, to allow their connection to be observed. Accordingly considerations of this kind, including those which are once more directed to the concept of freedom in the practical use of the pure reason, must not be re- garded as an interpolation serving only to fill up the gaps in the critical system of speculative reason (for this is for its own purpose complete), or like the props and buttresses which in a hastily con- structed building are often added afterwards; but as true members
8
which make the connexion of the system plain, and show us con- cepts, here presented as real, which there could only be presented problematically. This remark applies especially to the concept of freedom, respecting which one cannot but observe with surprise that so many boast of being able to understand it quite well and to explain its possibility, while they regard it only psychologically, whereas if they had studied it in a transcendental point of view, they must have recognized that it is not only indispensable as a problem- atical concept, in the complete use of speculative reason, but also quite incomprehensible; and if they afterwards came to consider its practical use, they must needs have come to the very mode of deter- mining the principles of this, to which they are now so loth to as- sent. The concept of freedom is the stone of stumbling for all em- piricists, but at the same time the key to the loftiest practical prin- ciples for critical moralists, who perceive by its means that they must necessarily proceed by a rational method. For this reason I beg the reader not to pass lightly over what is said of this concept at the end of the Analytic.
I must leave it to those who are acquainted with works of this kind to judge whether such a system as that of the practical reason, which is here developed from the critical examination of it, has cost much or little trouble, especially in seeking not to miss the true point of view from which the whole can be rightly sketched. It pre- supposes, indeed, the Fundamental Principles of the Metaphysic of Morals, but only in so far as this gives a preliminary acquaintance with the principle of duty, and assigns and justifies a definite for- mula thereof; in other respects it is independent. * It results from
* 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 prin- ciple 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 who- ever 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.
Immanuel Kant
? 9
The Critique of Practical Reason
the nature of this practical faculty itself that the complete classifica- tion of all practical sciences cannot be added, as in the critique of the speculative reason. For it is not possible to define duties spe- cially, as human duties, with a view to their classification, until the subject of this definition (viz. , man) is known according to his ac- tual nature, at least so far as is necessary with respect to duty; this, however, does not belong to a critical examination of the practical reason, the business of which is only to assign in a complete manner the principles of its possibility, extent, and limits, without special reference to human nature. The classification then belongs to the system of science, not to the system of criticism.
In the second part of the Analytic I have given, as I trust, a suffi- cient answer to the objection of a truth-loving and acute critic* of the Fundamental Principles of the Metaphysic of Morals- a critic always worthy of respect- the objection, namely, that the notion of good was not established before the moral principle, as he thinks it ought to have been. ** I have also had regard to many of the objec-
* [See Kant's "Das mag in der Theoric ricktig seyn," etc. Werke, vol. vii, p. 182. ] ** 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 prin- ciple 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 be- coming by means of its ideas the cause of the actual existence of the ob- jects 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
10
? tions which have reached me from men who show that they have at heart the discovery of the truth, and I shall continue to do so (for those who have only their old system before their eyes, and who have already settled what is to be approved or disapproved, do not desire any explanation which might stand in the way of their own private opinion. )
When we have to study a particular faculty of the human mind in its sources, its content, and its limits; then from the nature of hu- man knowledge we must begin with its parts, with an accurate and complete exposition of them; complete, namely, so far as is possible in the present state of our knowledge of its elements. But there is another thing to be attended to which is of a more philosophical and architectonic character, namely, to grasp correctly the idea of the whole, and from thence to get a view of all those parts as mutu- ally related by the aid of pure reason, and by means of their deriva- tion from the concept of the whole. This is only possible through the most intimate acquaintance with the system; and those who find the first inquiry too troublesome, and do not think it worth their while to attain such an acquaintance, cannot reach the second stage, namely, the general view, which is a synthetical return to that which had previously been given analytically. It is no wonder then if they find inconsistencies everywhere, although the gaps which these indicate are not in the system itself, but in their own incoherent train of thought.
I have no fear, as regards this treatise, of the reproach that I wish to introduce a new language, since the sort of knowledge here in
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 con- tain nothing empirical.
And this need is not a merely hypothetical one for the arbitrary purposes of speculation, that we must assume something if we wish in speculation to carry reason to its utmost limits, but it is a need which has the force of law to assume something without which that cannot be which we must inevitably set before us as the aim of our action.
It would certainly be more satisfactory to our speculative reason if it could solve these problems for itself without this circuit and pre- serve the solution for practical use as a thing to be referred to, but in fact our faculty of speculation is not so well provided. Those who boast of such high knowledge ought not to keep it back, but to exhibit it publicly that it may be tested and appreciated. They want to prove: very good, let them prove; and the critical philosophy lays its arms at their feet as the victors. Quid statis? Nolint. Atqui licet esse beatis. As they then do not in fact choose to do so, probably because they cannot, we must take up these arms again in order to seek in the mortal use of reason, and to base on this, the notions of
6
God, freedom, and immortality, the possibility of which specula- tion cannot adequately prove.
Here first is explained the enigma of the critical philosophy, viz. : how we deny objective reality to the supersensible use of the catego- ries in speculation and yet admit this reality with respect to the ob- jects of pure practical reason. This must at first seem inconsistent as long as this practical use is only nominally known. But when, by a thorough analysis of it, one becomes aware that the reality spoken of does not imply any theoretical determination of the categories and extension of our knowledge to the supersensible; but that what is meant is that in this respect an object belongs to them, because either they are contained in the necessary determination of the will a priori, or are inseparably connected with its object; then this inconsistency disappears, because the use we make of these concepts is different from what speculative reason requires. On the other hand, there now appears an unexpected and very satisfactory proof of the consistency of the speculative critical philosophy. For whereas it insisted that the objects of experience as such, including our own subject, have only the value of phenomena, while at the same time things in themselves must be supposed as their basis, so that not everything supersensible was to be regarded as a fiction and its concept as empty; so now prac- tical reason itself, without any concert with the speculative, assures reality to a supersensible object of the category of causality, viz. , free- dom, although (as becomes a practical concept) only for practical use; and this establishes on the evidence of a fact that which in the former case could only be conceived. By this the strange but certain doctrine of the speculative critical philosophy, that the thinking subject is to itself in internal intuition only a phenomenon, obtains in the critical examination of the practical reason its full confirmation, and that so thoroughly that we should be compelled to adopt this doctrine, even if the former had never proved it at all. *
* The union 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.
Immanuel Kant
? 7
The Critique of Practical Reason
By this also I can understand why the most considerable objec- tions which I have as yet met with against the Critique turn about these two points, namely, on the one side, the objective reality of the categories as applied to noumena, which is in the theoretical department of knowledge denied, in the practical affirmed; and on the other side, the paradoxical demand to regard oneself qua subject of freedom as a noumenon, and at the same time from the point of view of physical nature as a phenomenon in one's own empirical consciousness; for as long as one has formed no definite notions of morality and freedom, one could not conjecture on the one side what was intended to be the noumenon, the basis of the alleged phenomenon, and on the other side it seemed doubtful whether it was at all possible to form any notion of it, seeing that we had pre- viously assigned all the notions of the pure understanding in its theoretical use exclusively to phenomena. Nothing but a detailed criticism of the practical reason can remove all this misapprehen- sion and set in a clear light the consistency which constitutes its greatest merit.
So much by way of justification of the proceeding by which, in this work, the notions and principles of pure speculative reason which have already undergone their special critical examination are, now and then, again subjected to examination. This would not in other cases be in accordance with the systematic process by which a sci- ence is established, since matters which have been decided ought only to be cited and not again discussed. In this case, however, it was not only allowable but necessary, because reason is here consid- ered in transition to a different use of these concepts from what it had made of them before. Such a transition necessitates a compari- son of the old and the new usage, in order to distinguish well the new path from the old one and, at the same time, to allow their connection to be observed. Accordingly considerations of this kind, including those which are once more directed to the concept of freedom in the practical use of the pure reason, must not be re- garded as an interpolation serving only to fill up the gaps in the critical system of speculative reason (for this is for its own purpose complete), or like the props and buttresses which in a hastily con- structed building are often added afterwards; but as true members
8
which make the connexion of the system plain, and show us con- cepts, here presented as real, which there could only be presented problematically. This remark applies especially to the concept of freedom, respecting which one cannot but observe with surprise that so many boast of being able to understand it quite well and to explain its possibility, while they regard it only psychologically, whereas if they had studied it in a transcendental point of view, they must have recognized that it is not only indispensable as a problem- atical concept, in the complete use of speculative reason, but also quite incomprehensible; and if they afterwards came to consider its practical use, they must needs have come to the very mode of deter- mining the principles of this, to which they are now so loth to as- sent. The concept of freedom is the stone of stumbling for all em- piricists, but at the same time the key to the loftiest practical prin- ciples for critical moralists, who perceive by its means that they must necessarily proceed by a rational method. For this reason I beg the reader not to pass lightly over what is said of this concept at the end of the Analytic.
I must leave it to those who are acquainted with works of this kind to judge whether such a system as that of the practical reason, which is here developed from the critical examination of it, has cost much or little trouble, especially in seeking not to miss the true point of view from which the whole can be rightly sketched. It pre- supposes, indeed, the Fundamental Principles of the Metaphysic of Morals, but only in so far as this gives a preliminary acquaintance with the principle of duty, and assigns and justifies a definite for- mula thereof; in other respects it is independent. * It results from
* 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 prin- ciple 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 who- ever 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.
Immanuel Kant
? 9
The Critique of Practical Reason
the nature of this practical faculty itself that the complete classifica- tion of all practical sciences cannot be added, as in the critique of the speculative reason. For it is not possible to define duties spe- cially, as human duties, with a view to their classification, until the subject of this definition (viz. , man) is known according to his ac- tual nature, at least so far as is necessary with respect to duty; this, however, does not belong to a critical examination of the practical reason, the business of which is only to assign in a complete manner the principles of its possibility, extent, and limits, without special reference to human nature. The classification then belongs to the system of science, not to the system of criticism.
In the second part of the Analytic I have given, as I trust, a suffi- cient answer to the objection of a truth-loving and acute critic* of the Fundamental Principles of the Metaphysic of Morals- a critic always worthy of respect- the objection, namely, that the notion of good was not established before the moral principle, as he thinks it ought to have been. ** I have also had regard to many of the objec-
* [See Kant's "Das mag in der Theoric ricktig seyn," etc. Werke, vol. vii, p. 182. ] ** 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 prin- ciple 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 be- coming by means of its ideas the cause of the actual existence of the ob- jects 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
10
? tions which have reached me from men who show that they have at heart the discovery of the truth, and I shall continue to do so (for those who have only their old system before their eyes, and who have already settled what is to be approved or disapproved, do not desire any explanation which might stand in the way of their own private opinion. )
When we have to study a particular faculty of the human mind in its sources, its content, and its limits; then from the nature of hu- man knowledge we must begin with its parts, with an accurate and complete exposition of them; complete, namely, so far as is possible in the present state of our knowledge of its elements. But there is another thing to be attended to which is of a more philosophical and architectonic character, namely, to grasp correctly the idea of the whole, and from thence to get a view of all those parts as mutu- ally related by the aid of pure reason, and by means of their deriva- tion from the concept of the whole. This is only possible through the most intimate acquaintance with the system; and those who find the first inquiry too troublesome, and do not think it worth their while to attain such an acquaintance, cannot reach the second stage, namely, the general view, which is a synthetical return to that which had previously been given analytically. It is no wonder then if they find inconsistencies everywhere, although the gaps which these indicate are not in the system itself, but in their own incoherent train of thought.
I have no fear, as regards this treatise, of the reproach that I wish to introduce a new language, since the sort of knowledge here in
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 con- tain nothing empirical. Such precaution is very desirable in all philosophy and yet is often neglected; namely, not to prejudge questions by adventur- ing 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.
Immanuel Kant
? 11
The Critique of Practical Reason
question has itself somewhat of an everyday character. Nor even in the case of the former critique could this reproach occur to anyone who had thought it through and not merely turned over the leaves. To invent new words where the language has no lack of expressions for given notions is a childish effort to distinguish oneself from the crowd, if not by new and true thoughts, yet by new patches on the old garment. If, therefore, the readers of that work know any more familiar expressions which are as suitable to the thought as those seem to me to be, or if they think they can show the futility of these thoughts themselves and hence that of the expression, they would, in the first case, very much oblige me, for I only desire to be under- stood: and, in the second case, they would deserve well of philoso- phy. But, as long as these thoughts stand, I very much doubt that suitable and yet more common expressions for them can be found. *
* 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 pre- cept (for example, the solution of all problems of geometry and mechan- ics); the latter, what is similarly related to a law actually present in the reason; and this distinction is not quite foreign even to common lan- guage, 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
? 12
In this manner, then, the a priori principles of two faculties of the mind, the faculty of cognition and that of desire, would be found and determined as to the conditions, extent, and limits of their use, and thus a sure foundation be paid for a scientific system of phi- losophy, both theoretic and practical.
Nothing worse could happen to these labours than that anyone should make the unexpected discovery that there neither is, nor can be, any a priori knowledge at all. But there is no danger of this. This would be the same thing as if one sought to prove by reason that there is no reason. For we only say that we know something by reason, when we are conscious that we could have known it, even if it had not been given to us in experience; hence rational knowledge and knowledge a priori are one and the same. It is a clear contradic- tion to try to extract necessity from a principle of experience (ex pumice aquam), and to try by this to give a judgement true univer- sality (without which there is no rational inference, not even infer- ence from analogy, which is at least a presumed universality and objective necessity). To substitute subjective necessity, that is, cus- tom, for objective, which exists only in a priori judgements, is to deny to reason the power of judging about the object, i. e. , of know- ing it, and what belongs to it. It implies, for example, that we must
which also the 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 postu- lates 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 practi- cal 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.
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not say of something which often or always follows a certain ante- cedent state that we can conclude from this to that (for this would imply objective necessity and the notion of an a priori connexion), but only that we may expect similar cases (just as animals do), that is that we reject the notion of cause altogether as false and a mere delusion. As to attempting to remedy this want of objective and consequently universal validity by saying that we can see no ground for attributing any other sort of knowledge to other rational beings, if this reasoning were valid, our ignorance would do more for the enlargement of our knowledge than all our meditation. For, then, on this very ground that we have no knowledge of any other ratio- nal beings besides man, we should have a right to suppose them to be of the same nature as we know ourselves to be: that is, we should really know them. I omit to mention that universal assent does not prove the objective validity of a judgement (i. e. , its validity as a cognition), and although this universal assent should accidentally happen, it could furnish no proof of agreement with the object; on the contrary, it is the objective validity which alone constitutes the basis of a necessary universal consent.
Hume would be quite satisfied with this system of universal empiri- cism, for, as is well known, he desired nothing more than that, in- stead of ascribing any objective meaning to the necessity in the con- cept of cause, a merely subjective one should be assumed, viz. , cus- tom, in order to deny that reason could judge about God, freedom, and immortality; and if once his principles were granted, he was cer- tainly well able to deduce his conclusions therefrom, with all logical coherence. But even Hume did not make his empiricism so universal as to include mathematics. He holds the principles of mathematics to be analytical; and if his were correct, they would certainly be apodeictic also: but we could not infer from this that reason has the faculty of forming apodeictic judgements in philosophy also- that is to say, those which are synthetical judgements, like the judgement of causality. But if we adopt a universal empiricism, then mathematics will be included.
Now if this science is in contradiction with a reason that admits only empirical principles, as it inevitably is in the antinomy in which mathematics prove the infinite divisibility of space, which empiri-
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cism cannot admit; then the greatest possible evidence of demon- stration is in manifest contradiction with the alleged conclusions from experience, and we are driven to ask, like Cheselden's blind patient, "Which deceives me, sight or touch? " (for empiricism is based on a necessity felt, rationalism on a necessity seen). And thus universal empiricism reveals itself as absolute scepticism. It is erro- neous to attribute this in such an unqualified sense to Hume,* since he left at least one certain touchstone (which can only be found in a priori principles), although experience consists not only of feelings, but also of judgements.
However, as in this philosophical and critical age such empiricism can scarcely be serious, and it is probably put forward only as an intellectual exercise and for the purpose of putting in a clearer light, by contrast, the necessity of rational a priori principles, we can only be grateful to those who employ themselves in this otherwise unin- structive labour.
Immanuel Kant
? * Names that designate the followers of a sect have always been accompa- nied with much injustice; just as if one said, "N is an Idealist. " For al- though 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.
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The Critique of Practical Reason
INTRODUCTION
Of the Idea of a Critique of Practical Reason
THE THEORETICAL USE of reason was concerned with objects of the cognitive faculty only, and a critical examination of it with refer- ence to this use applied properly only to the pure faculty of cogni- tion; because this raised the suspicion, which was afterwards con- firmed, that it might easily pass beyond its limits, and be lost among unattainable objects, or even contradictory notions. It is quite dif- ferent with the practical use of reason. In this, reason is concerned with the grounds of determination of the will, which is a faculty either to produce objects corresponding to ideas, or to determine ourselves to the effecting of such objects (whether the physical power is sufficient or not); that is, to determine our causality. For here, reason can at least attain so far as to determine the will, and has always objective reality in so far as it is the volition only that is in question. The first question here then is whether pure reason of itself alone suffices to determine the will, or whether it can be a ground of determination only as dependent on empirical condi- tions. Now, here there comes in a notion of causality justified by the critique of the pure reason, although not capable of being presented empirically, viz. , that of freedom; and if we can now discover means of proving that this property does in fact belong to the human will (and so to the will of all rational beings), then it will not only be shown that pure reason can be practical, but that it alone, and not reason empirically limited, is indubitably practical; consequently, we shall have to make a critical examination, not of pure practical reason, but only of practical reason generally. For when once pure
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reason is shown to exist, it needs no critical examination. For reason itself contains the standard for the critical examination of every use of it. The critique, then, of practical reason generally is bound to prevent the empirically conditioned reason from claiming exclu- sively to furnish the ground of determination of the will. If it is proved that there is a [practical] reason, its employment is alone immanent; the empirically conditioned use, which claims supremacy, is on the contrary transcendent and expresses itself in demands and precepts which go quite beyond its sphere. This is just the opposite of what might be said of pure reason in its speculative employment.
However, as it is still pure reason, the knowledge of which is here the foundation of its practical employment, the general outline of the classification of a critique of practical reason must be arranged in accordance with that of the speculative. We must, then, have the Elements and the Methodology of it; and in the former an Analytic as the rule of truth, and a Dialectic as the exposition and dissolu- tion of the illusion in the judgements of practical reason. But the order in the subdivision of the Analytic will be the reverse of that in the critique of the pure speculative reason. For, in the present case, we shall commence with the principles and proceed to the con- cepts, and only then, if possible, to the senses; whereas in the case of the speculative reason we began with the senses and had to end with the principles. The reason of this lies again in this: that now we have to do with a will, and have to consider reason, not in its relation to objects, but to this will and its causality. We must, then, begin with the principles of a causality not empirically conditioned, after which the attempt can be made to establish our notions of the determin- ing grounds of such a will, of their application to objects, and fi- nally to the subject and its sense faculty. We necessarily begin with the law of causality from freedom, that is, with a pure practical prin- ciple, and this determines the objects to which alone it can be ap- plied.
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The Critique of Practical Reason
FIRST PART ELEMENTS OF
PURE PRACTICAL REASON
BOOK I. The Analytic of Pure Practical Reason.
CHAPTER I
Of the Principles of Pure Practical Reason.
I. DEFINITION.
PRACTICAL PRINCIPLES are propositions which contain a general de- termination of the will, having under it several practical rules. They are subjective, or maxims, when the condition is regarded by the subject as valid only for his own will, but are objective, or practical laws, when the condition is recognized as objective, that is, valid for the will of every rational being.
REMARK.
Supposing that pure reason contains in itself a practical motive, that is, one adequate to determine the will, then there are practical laws; otherwise all practical principles will be mere maxims. In case the will of a rational being is pathologically affected, there may occur a conflict of the maxims with the practical laws recognized by itself. For example, one may make it his maxim to let no injury pass unrevenged, and yet he may see that this is not a practical law, but
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only his own maxim; that, on the contrary, regarded as being in one and the same maxim a rule for the will of every rational being, it must contradict itself. In natural philosophy the principles of what happens, e. g. , the principle of equality of action and reaction in the communication of motion) are at the same time laws of nature; for the use of reason there is theoretical and determined by the nature of the object. In practical philosophy, i. e. , that which has to do only with the grounds of determination of the will, the principles which a man makes for himself are not laws by which one is inevitably bound; because reason in practical matters has to do with the sub- ject, namely, with the faculty of desire, the special character of which may occasion variety in the rule. The practical rule is always a prod- uct of reason, because it prescribes action as a means to the effect. But in the case of a being with whom reason does not of itself deter- mine the will, this rule is an imperative, i. e. , a rule characterized by "shall," which expresses the objective necessitation of the action and signifies that, if reason completely determined the will, the action would inevitably take place according to this rule. Imperatives, there- fore, are objectively valid, and are quite distinct from maxims, which are subjective principles. The former either determine the condi- tions of the causality of the rational being as an efficient cause, i. e. , merely in reference to the effect and the means of attaining it; or they determine the will only, whether it is adequate to the effect or not. The former would be hypothetical imperatives, and contain mere precepts of skill; the latter, on the contrary, would be categori- cal, and would alone be practical laws. Thus maxims are principles, but not imperatives. Imperatives themselves, however, when they are conditional (i. e. , do not determine the will simply as will, but only in respect to a desired effect, that is, when they are hypotheti- cal imperatives), are practical precepts but not laws. Laws must be sufficient to determine the will as will, even before I ask whether I have power sufficient for a desired effect, or the means necessary to produce it; hence they are categorical: otherwise they are not laws at all, because the necessity is wanting, which, if it is to be practical, must be independent of conditions which are pathological and are therefore only contingently connected with the will. Tell a man, for example, that he must be industrious and thrifty in youth, in order
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that he may not want in old age; this is a correct and important practical precept of the will. But it is easy to see that in this case the will is directed to something else which it is presupposed that it desires; and as to this desire, we must leave it to the actor himself whether he looks forward to other resources than those of his own acquisition, or does not expect to be old, or thinks that in case of future necessity he will be able to make shift with little. Reason, from which alone can spring a rule involving necessity, does, indeed, give necessity to this precept (else it would not be an imperative), but this is a necessity dependent on subjective conditions, and cannot be sup- posed in the same degree in all subjects. But that reason may give laws it is necessary that it should only need to presuppose itself, because rules are objectively and universally valid only when they hold with- out any contingent subjective conditions, which distinguish one ra- tional being from another. Now tell a man that he should never make a deceitful promise, this is a rule which only concerns his will, whether the purposes he may have can be attained thereby or not; it is the volition only which is to be determined a priori by that rule. If now it is found that this rule is practically right, then it is a law, because it is a categorical imperative. Thus, practical laws refer to the will only, without considering what is attained by its causality, and we may disregard this latter (as belonging to the world of sense) in order to have them quite pure.
II. THEOREM I.
All practical principles which presuppose an object (matter) of the faculty of desire as the ground of determination of the will are em- pirical and can furnish no practical laws.
By the matter of the faculty of desire I mean an object the realiza- tion of which is desired. Now, if the desire for this object precedes the practical rule and is the condition of our making it a principle, then I say (in the first place) this principle is in that case wholly empirical, for then what determines the choice is the idea of an object and that relation of this idea to the subject by which its fac- ulty of desire is determined to its realization. Such a relation to the
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subject is called the pleasure in the realization of an object. This, then, must be presupposed as a condition of the possibility of deter- mination of the will. But it is impossible to know a priori of any idea of an object whether it will be connected with pleasure or pain, or be indifferent. In such cases, therefore, the determining principle of the choice must be empirical and, therefore, also the practical material principle which presupposes it as a condition.
In the second place, since susceptibility to a pleasure or pain can be known only empirically and cannot hold in the same degree for all rational beings, a principle which is based on this subjective condi- tion may serve indeed as a maxim for the subject which possesses this susceptibility, but not as a law even to him (because it is wanting in objective necessity, which must be recognized a priori); it follows, therefore, that such a principle can never furnish a practical law.
III. THEOREM II.
All material practical principles as such are of one and the same kind and come under the general principle of self-love or private happiness.
Pleasure arising from the idea of the idea of the existence of a thing, in so far as it is to determine the desire of this thing, is founded on the susceptibility of the subject, since it depends on the presence of an object; hence it belongs to sense (feeling), and not to under- standing, which expresses a relation of the idea to an object accord- ing to concepts, not to the subject according to feelings. It is, then, practical only in so far as the faculty of desire is determined by the sensation of agreeableness which the subject expects from the actual existence of the object. Now, a rational being's consciousness of the pleasantness of life uninterruptedly accompanying his whole exist- ence is happiness; and the principle which makes this the supreme ground of determination of the will is the principle of self-love. All material principles, then, which place the determining ground of the will in the pleasure or pain to be received from the existence of any object are all of the same kind, inasmuch as they all belong to the principle of self-love or private happiness.
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The Critique of Practical Reason
COROLLARY.
All material practical rules place the determining principle of the will in the lower desires; and if there were no purely formal laws of the will adequate to determine it, then we could not admit any higher desire at all.
REMARK I.
It is surprising that men, otherwise acute, can think it possible to distinguish between higher and lower desires, according as the ideas which are connected with the feeling of pleasure have their origin in the senses or in the understanding; for when we inquire what are the determining grounds of desire, and place them in some expected pleasantness, it is of no consequence whence the idea of this pleas- ing object is derived, but only how much it pleases. Whether an idea has its seat and source in the understanding or not, if it can only determine the choice by presupposing a feeling of pleasure in the subject, it follows that its capability of determining the choice depends altogether on the nature of the inner sense, namely, that this can be agreeably affected by it. However dissimilar ideas of ob- jects may be, though they be ideas of the understanding, or even of the reason in contrast to ideas of sense, yet the feeling of pleasure, by means of which they constitute the determining principle of the will (the expected satisfaction which impels the activity to the pro- duction of the object), is of one and the same kind, not only inas- much as it can only be known empirically, but also inasmuch as it affects one and the same vital force which manifests itself in the faculty of desire, and in this respect can only differ in degree from every other ground of determination. Otherwise, how could we compare in respect of magnitude two principles of determination, the ideas of which depend upon different faculties, so as to prefer that which affects the faculty of desire in the highest degree. The same man may return unread an instructive book which he cannot
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again obtain, in order not to miss a hunt; he may depart in the midst of a fine speech, in order not to be late for dinner; he may leave a rational conversation, such as he otherwise values highly, to take his place at the gaming-table; he may even repulse a poor man whom he at other times takes pleasure in benefiting, because he has only just enough money in his pocket to pay for his admission to the theatre. If the determination of his will rests on the feeling of the agreeableness or disagreeableness that he expects from any cause, it is all the same to him by what sort of ideas he will be affected. The only thing that concerns him, in order to decide his choice, is, how great, how long continued, how easily obtained, and how often re- peated, this agreeableness is. just as to the man who wants money to spend, it is all the same whether the gold was dug out of the moun- tain or washed out of the sand, provided it is everywhere accepted at the same value; so the man who cares only for the enjoyment of life does not ask whether the ideas are of the understanding or the senses, but only how much and how great pleasure they will give for the longest time. It is only those that would gladly deny to pure reason the power of determining the will, without the presupposition of any feeling, who could deviate so far from their own exposition as to describe as quite heterogeneous what they have themselves previ- ously brought under one and the same principle.