The Critique of Practical Reason - Immanuel Kant (classic books to read .txt) 📗

life that even on this account alone the most prudent choice of a rational Epicurean reflecting on the greatest advantage of life would declare itself on the side of moral conduct, and it may even be advisable to join this prospect of a cheerful enjoyment of life with that supreme motive which is already sufficient of itself; but only as a counterpoise to the attractions which vice does not fail to exhibit on the opposite side, and not so as, even in the smallest degree, to place in this the proper moving power when duty is in question. For that would be just the same as to wish to taint the purity of the moral disposition in its source. The majesty of duty has nothing to do with enjoyment of life; it has its special law and its special tribunal, and though the two should be never so well shaken together to be given well mixed, like medicine, to the sick soul, yet they will soon separate of themselves; and if they do not, the former will not act; and although physical life might gain somewhat in force, the moral life would fade away irrecoverably.

{BOOK_1|CHAPTER_3 ^paragraph 35}

Critical Examination of the Analytic of Pure Practical Reason.

By the critical examination of a science, or of a portion of it, which constitutes a system by itself, I understand the inquiry and proof why it must have this and no other systematic form, when we compare it with another system which is based on a similar faculty of knowledge. Now practical and speculative reason are based on the same faculty, so far as both are pure reason. Therefore the difference in their systematic form must be determined by the comparison of both, and the ground of this must be assigned.

The Analytic of pure theoretic reason had to do with the knowledge of such objects as may have been given to the understanding, and was obliged therefore to begin from intuition and consequently (as this is always sensible) from sensibility; and only after that could advance to concepts (of the objects of this intuition), and could only end with principles after both these had preceded. On the contrary, since practical reason has not to do with objects so as to know them, but with its own faculty of realizing them (in accordance with the knowledge of them), that is, with a will which is a causality, inasmuch as reason contains its determining principle; since, consequently, it has not to furnish an object of intuition, but as practical reason has to furnish only a law (because the notion of causality always implies the reference to a law which determines the existence of the many in relation to one another); hence a critical examination of the Analytic of reason, if this is to be practical reason (and this is properly the problem), must begin with the possibility of practical principles a priori. Only after that can it proceed to concepts of the objects of a practical reason, namely, those of absolute good and evil, in order to assign them in accordance with those principles (for prior to those principles they cannot possibly be given as good and evil by any faculty of knowledge), and only then could the section be concluded with the last chapter, that, namely, which treats of the relation of the pure practical reason to the sensibility and of its necessary influence thereon, which is a priori cognisable, that is, of the moral sentiment. Thus the Analytic of the practical pure reason has the whole extent of the conditions of its use in common with the theoretical, but in reverse order. The Analytic of pure theoretic reason was divided into transcendental Aesthetic and transcendental Logic, that of the practical reversely into Logic and Aesthetic of pure practical reason (if I may, for the sake of analogy merely, use these designations, which are not quite suitable). This logic again was there divided into the Analytic of concepts and that of principles: here into that of principles and concepts. The Aesthetic also had in the former case two parts, on account of the two kinds of sensible intuition; here the sensibility is not considered as a capacity of intuition at all, but merely as feeling (which can be a subjective ground of desire), and in regard to it pure practical reason admits no further division.

It is also easy to see the reason why this division into two parts with its subdivision was not actually adopted here (as one might have been induced to attempt by the example of the former critique).

For since it is pure reason that is here considered in its practical use, and consequently as proceeding from a priori principles, and not from empirical principles of determination, hence the division of the analytic of pure practical reason must resemble that of a syllogism; namely, proceeding from the universal in the major premiss (the moral principle), through a minor premiss containing a subsumption of possible actions (as good or evil) under the former, to the conclusion, namely, the subjective determination of the will (an interest in the possible practical good, and in the maxim founded on it). He who has been able to convince himself of the truth of the positions occurring in the Analytic will take pleasure in such comparisons; for they justly suggest the expectation that we may perhaps some day be able to discern the unity of the whole faculty of reason (theoretical as well as practical) and be able to derive all from one principle, which, is what human reason inevitably demands, as it finds complete satisfaction only in a perfectly systematic unity of its knowledge.

{BOOK_1|CHAPTER_3 ^paragraph 40}

If now we consider also the contents of the knowledge that we can have of a pure practical reason, and by means of it, as shown by the Analytic, we find, along with a remarkable analogy between it and the theoretical, no less remarkable differences. As regards the theoretical, the faculty of a pure rational cognition a priori could be easily and evidently proved by examples from sciences (in which, as they put their principles to the test in so many ways by methodical use, there is not so much reason as in common knowledge to fear a secret mixture of empirical principles of cognition). But, that pure reason without the admixture of any empirical principle is practical of itself, this could only be shown from the commonest practical use of reason, by verifying the fact, that every man’s natural reason acknowledges the supreme practical principle as the supreme law of his will-a law completely a priori and not depending on any sensible data. It was necessary first to establish and verify the purity of its origin, even in the judgement of this common reason, before science could take it in hand to make use of it, as a fact, that is, prior to all disputation about its possibility, and all the consequences that may be drawn from it. But this circumstance may be readily explained from what has just been said; because practical pure reason must necessarily begin with principles, which therefore must be the first data, the foundation of all science, and cannot be derived from it. It was possible to effect this verification of moral principles as principles of a pure reason quite well, and with sufficient certainty, by a single appeal to the judgement of common sense, for this reason, that anything empirical which might slip into our maxims as a determining principle of the will can be detected at once by the feeling of pleasure or pain which necessarily attaches to it as exciting desire; whereas pure practical reason positively refuses to admit this feeling into its principle as a condition. The heterogeneity of the determining principles (the empirical and rational) is clearly detected by this resistance of a practically legislating reason against every admixture of inclination, and by a peculiar kind of sentiment, which, however, does not precede the legislation of the practical reason, but, on the contrary, is produced by this as a constraint, namely, by the feeling of a respect such as no man has for inclinations of whatever kind but for the law only; and it is detected in so marked and prominent a manner that even the most uninstructed cannot fail to see at once in an example presented to him, that empirical principles of volition may indeed urge him to follow their attractions, but that he can never be expected to obey anything but the pure practical law of reason alone.

The distinction between the doctrine of happiness and the doctrine of morality, in the former of which empirical principles constitute the entire foundation, while in the second they do not form the smallest part of it, is the first and most important office of the Analytic of pure practical reason; and it must proceed in it with as much exactness and, so to speak, scrupulousness, as any geometer in his work. The philosopher, however, has greater difficulties to contend with here (as always in rational cognition by means of concepts merely without construction), because he cannot take any intuition as a foundation (for a pure noumenon). He has, however, this advantage that, like the chemist, he can at any time make an experiment with every man’s practical reason for the purpose of distinguishing the moral (pure) principle of determination from the empirical; namely, by adding the moral law (as a determining principle) to the empirically affected will (e.g., that of the man who would be ready to lie because he can gain something thereby). It is as if the analyst added alkali to a solution of lime in hydrochloric acid, the acid at once forsakes the lime, combines with the alkali, and the lime is precipitated. just in the same way, if to a man who is otherwise honest (or who for this occasion places himself only in thought in the position of an honest man), we present the moral law by which he recognises the worthlessness of the liar, his practical reason (in forming a judgement of what ought to be done) at once forsakes the advantage, combines with that which maintains in him respect for his own person (truthfulness), and the advantage after it has been separated and washed from every particle of reason (which is altogether on the side of duty) is easily weighed by everyone, so that it can enter into combination with reason in other cases, only not where it could be opposed to the moral law, which reason never forsakes, but most closely unites itself with.

But it does not follow that this distinction between the principle of happiness and that of morality is an opposition between them, and pure practical reason does not require that we should renounce all claim to happiness, but only that the moment duty is in question we should take no account of happiness. It may even in certain respects be a duty to provide for happiness; partly, because (including skill, wealth, riches) it contains means for the fulfilment of our duty; partly, because the absence of it (e.g., poverty) implies temptations to transgress our duty. But it can never be an immediate duty to promote our happiness, still less can it be the principle of all duty. Now, as all determining principles of the will, except the law of pure practical reason alone (the moral law), are all empirical and, therefore, as such, belong to the principle of happiness, they must all be kept apart from the supreme principle of morality and never be incorporated with it as a condition; since this would be to destroy all moral worth just as much as any empirical admixture with geometrical principles would destroy the certainty of mathematical evidence, which in Plato’s opinion is the most excellent thing in mathematics, even surpassing their utility.

Instead, however, of the deduction of the supreme principle of pure