Immanuel Kant: Critique of Practical Reason (excerpt, part 2)

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Critical Elucidation of the Analytic of Pure Practical Reason

The notion of causality as physical necessity, in opposition to the same notion as freedom, concerns only the existence of things so far as it is determinable in time, and, consequently, as phenomena, in opposition to their causality as things in themselves. Now if we take the attributes of existence of things in time for attributes of things in themselves (which is the common view), then it is impossible to reconcile the necessity of the causal relation with freedom; they are contradictory. For from the former it follows that every event, and consequently every action that takes place at a certain point of time, is a necessary result of what existed in time preceding. Now as time past is no longer in my power, hence every action that I perform must be the necessary result of certain determining grounds which are not in my power, that is, at the moment in which I am acting I am never free. Nay, even if I assume that my whole existence is independent on any foreign cause (for instance, God), so that the determining principles of my causality, and even of my whole existence, were not outside myself, yet this would not in the least transform that physical necessity into freedom. For at every moment of time I am still under the necessity of being determined to action by that which is not in my power, and the series of events infinite a parte priori, which I only continue according to a pre-determined order and could never begin of myself, would be a continuous physical chain, and therefore my causality would never be freedom.

If, then, we would attribute freedom to a being whose existence is determined in time, we cannot except him from the law of necessity as to all events in his existence and, consequently, as to his actions also; for that would be to hand him over to blind chance. Now as this law inevitably applies to all the causality of things, so far as their existence is determinable in time, it follows that if this were the mode in which we had also to conceive the existence of these things in themselves, freedom must be rejected as a vain and impossible conception. Consequently, if we would still save it, no other way remains but to consider that the existence of a thing, so far as it is determinable in time, and therefore its causality, according to the law of physical necessity, belong to appearance, and to attribute freedom to the same being as a thing in itself. This is certainly inevitable, if we would retain both these contradictory concepts together; but in application, when we try to explain their combination in one and the same action, great difficulties present themselves which seem to render such a combination impracticable.

When I say of a man who commits a theft that, by the law of causality, this deed is a necessary result of the determining causes in preceding time, then it was impossible that it could not have happened; how then can the judgement, according to the moral law, make any change, and suppose that it could have been omitted, because the law says that it ought to have been omitted; that is, how can a man be called quite free at the same moment, and with respect to the same action in which he is subject to an inevitable physical necessity? Some try to evade this by saying that the causes that determine his causality are of such a kind as to agree with a comparative notion of freedom. According to this, that is sometimes called a free effect, the determining physical cause of which lies within the acting thing itself, e.g., that which a projectile performs when it is in free motion, in which case we use the word freedom, because while it is in flight it is not urged by anything external; or as we call the motion of a clock a free motion, because it moves its hands itself, which therefore do not require to be pushed by external force; so although the actions of man are necessarily determined by causes which precede in time, we yet call them free, because these causes are ideas produced by our own faculties, whereby desires are evoked on occasion of circumstances, and hence actions are wrought according to our own pleasure. This is a wretched subterfuge with which some persons still let themselves be put off, and so think they have solved, with a petty word- jugglery, that difficult problem, at the solution of which centuries have laboured in vain, and which can therefore scarcely be found so completely on the surface. In fact, in the question about the freedom which must be the foundation of all moral laws and the consequent responsibility, it does not matter whether the principles which necessarily determine causality by a physical law reside within the subject or without him, or in the former case whether these principles are instinctive or are conceived by reason, if, as is admitted by these men themselves, these determining ideas have the ground of their existence in time and in the antecedent state, and this again in an antecedent, etc. Then it matters not that these are internal; it matters not that they have a psychological and not a mechanical causality, that is, produce actions by means of ideas and not by bodily movements; they are still determining principles of the causality of a being whose existence is determinable in time, and therefore under the necessitation of conditions of past time, which therefore, when the subject has to act, are no longer in his power. This may imply psychological freedom (if we choose to apply this term to a merely internal chain of ideas in the mind), but it involves physical necessity and, therefore, leaves no room for transcendental freedom, which must be conceived as independence on everything empirical, and, consequently, on nature generally, whether it is an object of the internal sense considered in time only, or of the external in time and space. Without this freedom (in the latter and true sense), which alone is practical a priori, no moral law and no moral imputation are possible. just for this reason the necessity of events in time, according to the physical law of causality, may be called the mechanism of nature, although we do not mean by this that things which are subject to it must be really material machines. We look here only to the necessity of the connection of events in a time-series as it is developed according to the physical law, whether the subject in which this development takes place is called automaton materiale when the mechanical being is moved by matter, or with Leibnitz spirituale when it is impelled by ideas; and if the freedom of our will were no other than the latter (say the psychological and comparative, not also transcendental, that is, absolute), then it would at bottom be nothing better than the freedom of a turnspit, which, when once it is wound up, accomplishes its motions of itself.

Now, in order to remove in the supposed case the apparent contradiction between freedom and the mechanism of nature in one and the same action, we must remember what was said in the Critique of Pure Reason, or what follows therefrom; viz., that the necessity of nature, which cannot co-exist with the freedom of the subject, appertains only to the attributes of the thing that is subject to time-conditions, consequently only to those of the acting subject as a phenomenon; that therefore in this respect the determining principles of every action of the same reside in what belongs to past time and is no longer in his power (in which must be included his own past actions and the character that these may determine for him in his own eyes as a phenomenon). But the very same subject, being on the other side conscious of himself as a thing in himself, considers his existence also in so far as it is not subject to time-conditions, and regards himself as only determinable by laws which he gives himself through reason; and in this his existence nothing is antecedent to the determination of his will, but every action, and in general every modification of his existence, varying according to his internal sense, even the whole series of his existence as a sensible being is in the consciousness of his supersensible existence nothing but the result, and never to be regarded as the determining principle, of his causality as a noumenon. In this view now the rational being can justly say of every unlawful action that he performs, that he could very well have left it undone; although as appearance it is sufficiently determined in the past, and in this respect is absolutely necessary; for it, with all the past which determines it, belongs to the one single phenomenon of his character which he makes for himself, in consequence of which he imputes the causality of those appearances to himself as a cause independent of sensibility.

With this agree perfectly the judicial sentences of that wonderful faculty in us which we call conscience. A man may use as much art as he likes in order to paint to himself an unlawful act, that he remembers, as an unintentional error, a mere oversight, such as one can never altogether avoid, and therefore as something in which he was carried away by the stream of physical necessity, and thus to make himself out innocent, yet he finds that the advocate who speaks in his favour can by no means silence the accuser within, if only he is conscious that at the time when he did this wrong he was in his senses, that is, in possession of his freedom; and, nevertheless, he accounts for his error from some bad habits, which by gradual neglect of attention he has allowed to grow upon him to such a degree that he can regard his error as its natural consequence, although this cannot protect him from the blame and reproach which he casts upon himself.


On the Dialectic of Pure Reason in Defining
the Conception of the Summum Bonum [“Highest Good”]

The conception of the summum itself contains an ambiguity which might occasion needless disputes if we did not attend to it. The summum may mean either the supreme (supremum) or the perfect (consummatum). The former is that condition which is itself unconditioned, i.e., is not subordinate to any other (originarium); the second is that whole which is not a part of a greater whole of the same kind (perfectissimum). It has been shown in the Analytic that virtue (as worthiness to be happy) is the supreme condition of all that can appear to us desirable, and consequently of all our pursuit of happiness, and is therefore the supreme good. But it does not follow that it is the whole and perfect good as the object of the desires of rational finite beings; for this requires happiness also, and that not merely in the partial eyes of the person who makes himself an end, but even in the judgement of an impartial reason, which regards persons in general as ends in themselves. For to need happiness, to deserve it, and yet at the same time not to participate in it, cannot be consistent with the perfect volition of a rational being possessed at the same time of all power, if, for the sake of experiment, we conceive such a being. Now inasmuch as virtue and happiness together constitute the possession of the summum bonum in a person, and the distribution of happiness in exact proportion to morality (which is the worth of the person, and his worthiness to be happy) constitutes the summum bonum of a possible world; hence this summum bonum expresses the whole, the perfect good, in which, however, virtue as the condition is always the supreme good, since it has no condition above it; whereas happiness, while it is pleasant to the possessor of it, is not of itself absolutely and in all respects good, but always presupposes morally right behaviour as its condition.

When two elements are necessarily united in one concept, they must be connected as reason and consequence, and this either so that their unity is considered as analytical (logical connection), or as synthetical (real connection) the former following the law of identity, the latter that of causality. The connection of virtue and happiness may therefore be understood in two ways: either the endeavour to be virtuous and the rational pursuit of happiness are not two distinct actions, but absolutely identical, in which case no maxim need be made the principle of the former, other than what serves for the latter; or the connection consists in this, that virtue produces happiness as something distinct from the consciousness of virtue, as a cause produces an effect.

The ancient Greek schools were, properly speaking, only two, and in determining the conception of the summum bonum these followed in fact one and the same method, inasmuch as they did not allow virtue and happiness to be regarded as two distinct elements of the summum bonum, and consequently sought the unity of the principle by the rule of identity; but they differed as to which of the two was to be taken as the fundamental notion. The Epicurean said: "To be conscious that one's maxims lead to happiness is virtue"; the Stoic said: "To be conscious of one's virtue is happiness." With the former, Prudence was equivalent to morality; with the latter, who chose a higher designation for virtue, morality alone was true wisdom.

While we must admire the men who in such early times tried all imaginable ways of extending the domain of philosophy, we must at the same time lament that their acuteness was unfortunately misapplied in trying to trace out identity between two extremely heterogeneous notions, those of happiness and virtue. But it agrees with the dialectical spirit of their times (and subtle minds are even now sometimes misled in the same way) to get rid of irreconcilable differences in principle by seeking to change them into a mere contest about words, and thus apparently working out the identity of the notion under different names, and this usually occurs in cases where the combination of heterogeneous principles lies so deep or so high, or would require so complete a transformation of the doctrines assumed in the rest of the philosophical system, that men are afraid to penetrate deeply into the real difference and prefer treating it as a difference in questions of form.

While both schools sought to trace out the identity of the practical principles of virtue and happiness, they were not agreed as to the way in which they tried to force this identity, but were separated infinitely from one another, the one placing its principle on the side of sense, the other on that of reason; the one in the consciousness of sensible wants, the other in the independence of practical reason on all sensible grounds of determination. According to the Epicurean, the notion of virtue was already involved in the maxim: "To promote one's own happiness"; according to the Stoics, on the other hand, the feeling of happiness was already contained in the consciousness of virtue. Now whatever is contained in another notion is identical with part of the containing notion, but not with the whole, and moreover two wholes may be specifically distinct, although they consist of the same parts; namely if the parts are united into a whole in totally different ways. The Stoic maintained that the virtue was the whole summum bonum, and happiness only the consciousness of possessing it, as making part of the state of the subject. The Epicurean maintained that happiness was the whole summum bonum, and virtue only the form of the maxim for its pursuit; viz., the rational use of the means for attaining it.

Now it is clear from the Analytic that the maxims of virtue and those of private happiness are quite heterogeneous as to their supreme practical principle, and, although they belong to one summum bonum which together they make possible, yet they are so far from coinciding that they restrict and check one another very much in the same subject. Thus the question: "How is the summum bonum practically possible?" still remains an unsolved problem, notwithstanding all the attempts at coalition that have hitherto been made. The Analytic has, however, shown what it is that makes the problem difficult to solve; namely, that happiness and morality are two specifically distinct elements of the summum bonum and, therefore, their combination cannot be analytically cognised (as if the man that seeks his own happiness should find by mere analysis of his conception that in so acting he is virtuous, or as if the man that follows virtue should in the consciousness of such conduct find that he is already happy ipso facto), but must be a synthesis of concepts. Now since this combination is recognised as a priori, and therefore as practically necessary, and consequently not as derived from experience, so that the possibility of the summum bonum does not rest on any empirical principle, it follows that the deduction [legitimation] of this concept must be transcendental. It is a priori (morally) necessary to produce the summum bonum by freedom of will: therefore the condition of its possibility must rest solely on a priori principles of cognition.

The Antinomy of Practical Reason

In the summum bonum which is practical for us, i.e., to be realized by our will, virtue and happiness are thought as necessarily combined, so that the one cannot be assumed by pure practical reason without the other also being attached to it. Now this combination (like every other) is either analytical or synthetical. It bas been shown that it cannot be analytical; it must then be synthetical and, more particularly, must be conceived as the connection of cause and effect, since it concerns a practical good, i.e., one that is possible by means of action; consequently either the desire of happiness must be the motive to maxims of virtue, or the maxim of virtue must be the efficient cause of happiness. The first is absolutely impossible, because (as was proved in the Analytic) maxims which place the determining principle of the will in the desire of personal happiness are not moral at all, and no virtue can be founded on them. But the second is also impossible, because the practical connection of causes and effects in the world, as the result of the determination of the will, does not depend upon the moral dispositions of the will, but on the knowledge of the laws of nature and the physical power to use them for one's purposes; consequently we cannot expect in the world by the most punctilious observance of the moral laws any necessary connection of happiness with virtue adequate to the summum bonum. Now, as the promotion of this summum bonum, the conception of which contains this connection, is a priori a necessary object of our will and inseparably attached to the moral law, the impossibility of the former must prove the falsity of the latter. If then the supreme good is not possible by practical rules, then the moral law also which commands us to promote it is directed to vain imaginary ends and must consequently be false.

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