§ 88. Limitation of the validity of the moral proof
Pure Reason, as a practical faculty, i.e. as the faculty of determining the free use of our causality by Ideas (pure rational concepts), not only comprises in the moral law a regulative principle of our actions, but supplies us at the same time with a subjective constitutive principle in the concept of an Object which Reason alone can think, and which is to be actualised by our actions in the world according to that law. The Idea of a final purpose in the employment of freedom according to moral laws has therefore subjective practical reality. We are a priori determined by Reason to promote with all our powers the summum bonum [Weltbeste] which consists in the combination of the greatest welfare of rational beings with the highest condition of the good in itself, i.e. in universal happiness conjoined with morality most accordant to law. In this final purpose the possibility of one part, happiness, is empirically conditioned, i.e. dependent on the constitution of nature (which may or may not agree with this purpose) and is in a theoretical aspect problematical; whilst the other part, morality, in respect of which we are free from the effects of nature, stands fast a priori as to its possibility, and is dogmatically certain. It is then requisite for the objective theoretical reality of the concept of the final purpose of rational beings, that we should not only have a priori presupposed a final purpose for ourselves, but also that the creation, i.e. the world itself, should have as regards its existence a final purpose, which if it could be proved a priori would add objectivity to the subjective reality of the final purpose [of rational beings]. For if the creation has on the whole a final purpose, we cannot think it otherwise than as harmonising with the moral purpose (which alone makes the concept of a purpose possible). Now we find without doubt purposes in the world, and physical Teleology exhibits them in such abundance, that if we judge in accordance with Reason, we have ground for assuming as a principle in the investigation of nature that nothing in nature is without a purpose; but the final purpose of nature we seek there in vain. This can and must therefore, as its Idea only lies in Reason, be sought as regards its objective possibility only in rational beings. And the practical Reason of these latter not only supplies this final purpose; it also determines this concept in respect of the conditions under which alone a final purpose of creation can be thought by us.
The question is now, whether the objective reality of the concept of a final purpose of creation cannot be exhibited adequately to the theoretical requirements of pure Reason—if not apodictically for the determinant Judgement yet adequately for the maxims of the theoretical reflective Judgement? This is the least one could expect from theoretical philosophy, which undertakes to combine the moral purpose with natural purposes by means of the Idea of one single purpose; but yet this little is far more than it can accomplish.
According to the principle of the theoretical reflective Judgement we should say: if we have ground for assuming for the purposive products of nature a supreme Cause of nature—whose causality in respect of the actuality of creation is of a different kind from that required for the mechanism of nature, i.e. must be thought as the causality of an Understanding—we have also sufficient ground for thinking in this original Being not merely the purposes everywhere in nature but also a final purpose. This is not indeed a final purpose by which we can explain the presence of such a Being, but one of which we may at least convince ourselves (as was the case in physical Teleology) that we can make the possibility of such a world conceivable, not merely according to purposes, but only through the fact that we ascribe to its existence a final purpose.
But a final purpose is merely a concept of our practical Reason, and can be inferred from no data of experience for the theoretical judging of nature, nor can it be applied to the cognition of nature. No use of this concept is possible except its use for practical Reason according to moral laws; and the final purpose of creation is that constitution of the world which harmonises with that which alone we can put forward definitely according to laws, viz. the final purpose of our pure practical Reason, in so far as it is to be practical.— Now we have in the moral law, which enjoins on us in a practical point of view the application of our powers to the accomplishment of this final purpose, a ground for assuming its possibility and practicability, and consequently too (because without the concurrence of nature with a condition not in our power, its accomplishment would be impossible) a nature of things harmonious with it. Hence we have a moral ground for thinking in a world also a final purpose of creation.
We have not yet advanced from moral Teleology to a Theology, i.e. to the being of a moral Author of the world, but only to a final purpose of creation which is determined in this way. But in order to account for this creation, i.e. the existence of things, in accordance with a final purpose, we must assume not only first an intelligent Being (for the possibility of things of nature which we are compelled to judge of as purposes), but also a moral Being, as author of the world, i.e. a God. This second conclusion is of such a character that we see it holds merely for the Judgement according to concepts of practical Reason, and as such for the reflective and not the determinant Judgement. It is true that in us morally practical Reason is essentially different in its principles from technically practical Reason. But we cannot assume that it must be so likewise in the supreme World-Cause, regarded as Intelligence, and that a peculiar mode of its causality is requisite for the final purpose, different from that which is requisite merely for purposes of nature. We cannot therefore assume that in our final purpose we have not merely a moral ground for admitting a final purpose of creation (as an effect), but also for admitting a moral Being as the original ground of creation. But we may well say, that, according to the constitution of our rational faculty, we cannot comprehend the possibility of such a purposiveness in respect of the moral law, and its Object, as there is in this final purpose, apart from an Author and Governor of the world, who is at the same time its moral Lawgiver.
The actuality of a highest morally-legislating Author is therefore sufficiently established merely for the practical use of our Reason, without determining anything theoretically as regards its being. For Reason requires, in respect of the possibility of its purpose, which is given to us independently by its own legislation, an Idea through which the inability to follow up this purpose, according to the mere natural concepts of the world, is removed (sufficiently for the reflective Judgement). Thus this Idea gains practical reality, although all means of creating such for it in a theoretical point of view, for the explanation of nature and determination of the supreme Cause, are entirely wanting for speculative cognition. For the theoretical reflective Judgement physical Teleology sufficiently proves from the purposes of nature an intelligent World-Cause; for the practical Judgement moral Teleology establishes it by the concept of a final purpose, which it is forced to ascribe to creation in a practical point of view. The objective reality of the Idea of God, as moral Author of the world, cannot, it is true, be established by physical purposes alone. But nevertheless, if the cognition of these purposes is combined with that of the moral purpose, they are, by virtue of the maxim of pure Reason which bids us seek unity of principles so far as is possible, of great importance for the practical reality of that Idea, by bringing in the reality which it has for the Judgement in a theoretical point of view.
To prevent a misunderstanding which may easily arise, it is in the highest degree needful to remark that, in the first place, we can think these properties of the highest Being only according to analogy. How indeed could we explore the nature of that, to which experience can show us nothing similar? Secondly, in this way we only think the supreme Being; we cannot thereby cognise Him and ascribe anything theoretically to Him. It would be needful for the determinant Judgement in the speculative aspect of our Reason, to consider what the supreme World-Cause is in Himself. But here we are only concerned with the question what concept we can form of Him, according to the constitution of our cognitive faculties; and whether we have to assume His existence in order merely to furnish practical reality to a purpose, which pure Reason without any such presupposition enjoins upon us a priori to bring about with all our powers, i.e. in order to be able to think as possible a designed effect. Although that concept may be transcendent for the speculative Reason, and the properties which we ascribe to the Being thereby thought may, objectively used, conceal an anthropomorphism in themselves; yet the design of its use is not to determine the nature of that Being which is unattainable by us, but to determine ourselves and our will accordingly. We may call a cause after the concept which we have of its effect (though only in reference to this relation), without thereby meaning to determine internally its inner constitution, by means of the properties which can be made known to us solely by similar causes and must be given in experience. For example, amongst other properties we ascribe to the soul a vis locomotiva because bodily movements actually arise whose cause lies in the representation of them; without therefore meaning to ascribe to it the only mode [of action] that we know in moving forces (viz. by attraction, pressure, impulse, and consequently motion, which always presuppose an extended being). Just so we must assume something, which contains the ground of the possibility and practical reality, i.e. the practicability, of a necessary moral final purpose; but we can think of this, in accordance with the character of the effect expected of it, as a wise Being governing the world according to moral laws, and, conformably to the constitution of our cognitive faculties, as a cause of things distinct from nature, only in order to express the relation of this Being (which transcends all our cognitive faculties) to the Objects of our practical Reason. We do not pretend thus to ascribe to it theoretically the only causality of this kind known to us, viz. an Understanding and a Will: we do not even pretend to distinguish objectively the causality thought in this Being, as regards what is for us final purpose, from the causality thought in it as regards nature (and its purposive determinations in general). We can only assume this distinction as subjectively necessary by the constitution of our cognitive faculties, and as valid for the reflective, not for the objectively determinant Judgement. But if we come to practice, then such a regulative principle (of prudence or wisdom) [commanding us] to act conformably to that as purpose, which by the constitution of our cognitive faculties can only be thought as possible in a certain way, is at the same constitutive, i.e. practically determinant. Nevertheless, as a principle for judging of the objective possibility of things, it is no way theoretically determinant (i.e. it does not say that the only kind of possibility which belongs to the Object is that which belongs to our thinking faculty), but is a mere regulative principle for the reflective Judgement.
Remark
This moral proof is not one newly discovered, although perhaps its basis is newly set forth; since it has lain in man’s rational faculty from its earliest germ, and is only continually developed with its advancing cultivation. So soon as men begin to reflect upon right and wrong—at a time when, quite indifferent as to the purposiveness of nature, they avail themselves of it without thinking anything more of it than that it is the accustomed course of nature—this judgement is inevitable, viz. that the issue cannot be the same, whether a man has behaved candidly or falsely, fairly or violently, even though up to his life’s end, as far as can be seen, he has met with no happiness for his virtues, no punishment for his vices. It is as if they perceived a voice within [saying] that the issue must be different. And so there must lie hidden in them a representation, however obscure, of something after which they feel themselves bound to strive; with which such a result would not agree,—with which, if they looked upon the course of the world as the only order of things, they could not harmonise that inner purposive determination of their minds. Now they might represent in various rude fashions the way in which such an irregularity could be adjusted (an irregularity which must be far more revolting to the human mind than the blind chance that we are sometimes willing to use as a principle for judging of nature). But they could never think any other principle of the possibility of the unification of nature with its inner ethical laws, than a supreme Cause governing the world according to moral laws; because a final purpose in them proposed as duty, and a nature without any final purpose beyond them in which that purpose might be actualised, would involve a contradiction. As to the [inner][136] constitution of that World-Cause they could contrive much nonsense. But that moral relation in the government of the world would remain always the same, which by the uncultivated Reason, considered as practical, is universally comprehensible, but with which the speculative Reason can make far from the like advance.—And in all probability attention would be directed first by this moral interest to the beauty and the purposes in nature, which would serve excellently to strengthen this Idea though they could not be the foundation of it. Still less could that moral interest be dispensed with, because it is only in reference to the final purpose that the investigation of the purposes of nature acquires that immediate interest which displays itself in such a great degree in the admiration of them without any reference to the advantage to be derived from them.