are determinations of assent which differ not merely in degree but in kind), in order to present plainly the state of the mind in this proof in its whole clearness, and to be able to subject it frankly to the closest examination.
But a proof which is intended to convince, can again be of two kinds; either deciding what the object is _in itself_, or what it is _for us_ (for men in general) according to our necessary rational principles of judgement (proof κατ’ ἀλήθειαν or κατ’ ἄνθρωπον, the last word being taken in its universal signification of man in general). In the first case it is based on adequate principles for the determinant Judgement, in the second for the reflective Judgement. In the latter case it can never, when resting on merely theoretical principles, tend to conviction; but if a practical principle of Reason (which is therefore universally and necessarily valid) lies at its basis, it may certainly lay claim to conviction adequate in a pure practical point of view, _i.e._ to moral conviction. But a proof _tends to conviction_, though without convincing, if it is [merely][139] brought on the way thereto; _i.e._ if it contains in itself only objective grounds, which although not attaining to certainty are yet of such a kind that they do not serve merely for persuasion as subjective grounds of the judgement.[140] All theoretical grounds of proof resolve themselves either into: (1) Proofs by logically strict _Syllogisms of Reason_; or where this is not the case, (2) _Conclusions_ according to _analogy_; or where this also has no place, (3) _Probable opinion_; or finally, which has the least weight, (4) Assumption of a merely possible ground of explanation, _i.e._ _Hypothesis_.--Now I say that all grounds of proof in general, which aim at theoretical conviction, can bring about no belief of this kind from the highest to the lowest degree, if there is to be proved the proposition of the _existence_ of an original Being, as a God, in the signification adequate to the whole content of this concept; viz. a _moral_ Author of the world, by whom the final purpose of creation is at the same time supplied.
(1.) As to the _logically accurate_ proof proceeding from universal to particular, we have sufficiently established in the Critique the following: Since no intuition possible for us corresponds to the concept of a Being that is to be sought beyond nature--whose concept therefore, so far as it is to be theoretically determined by synthetical predicates, remains always problematical for us--there is absolutely no cognition of it to be had (by which the extent of our theoretical knowledge is in the least enlarged). The particular concept of a supersensible Being cannot be subsumed under the universal principles of the nature of things, in order to conclude from them to it, because those principles are valid simply for nature, as an object of sense.
(2.) We can indeed _think_ one of two dissimilar things, even in the very point of their dissimilarity, in accordance with the _analogy_[141] of the other; but we cannot, from that wherein they are dissimilar, _conclude_ from the one to the other by analogy, _i.e._ transfer from the one to the other this sign of specific distinction.
Thus I can, according to the analogy of the law of the equality of action and reaction in the mutual attraction and repulsion of bodies, also conceive of the association of the members of a commonwealth according to rules of right; but I cannot transfer to it those specific determinations (material attraction or repulsion), and ascribe them to the citizens in order to constitute a system called a state.--Just so we can indeed conceive of the causality of the original Being in respect of the things of the world, as natural purposes, according to the analogy of an Understanding, as ground of the forms of certain products which we call works of art (for this only takes place on behalf of the theoretical or practical use that we have to make by our cognitive faculty of this concept in respect of the natural things in the world according to a certain principle). But we can in no way conclude according to analogy, because in the case of beings of the world Understanding must be ascribed to the cause of an effect which is judged artificial, that in respect of nature the same causality which we perceive in men attaches also to the Being which is quite distinct from nature. For this concerns the very point of dissimilarity which is thought between a cause sensibly conditioned in respect of its effects and the supersensible original Being itself in our concept of it, and which therefore cannot be transferred from one to the other.-- In the very fact that I must conceive the divine causality only according to the analogy of an Understanding (which faculty we know in no other being than in sensibly-conditioned man) lies the prohibition to ascribe to it this Understanding in its peculiar signification.[142] (3.) _Opinion_ finds in _a priori_ judgements no place whatever, for by them we either cognise something as quite certain or else cognise nothing at all. But if the given grounds of proof from which we start (as here from the purposes in the world) are empirical, then we cannot even with their aid form any opinion as to anything beyond the world of sense, nor can we concede to such venturesome judgements the smallest claim to probability. For probability is part of a certainty possible in a certain series of grounds (its grounds compare with the sufficient ground as parts with a whole), the insufficient ground of which must be susceptible of completion. But since, as determining grounds of one and the same judgement, they must be of the same kind, for otherwise they would not together constitute a whole (such as certainty is), one part of them cannot lie within the bounds of possible experience and another outside all possible experience. Consequently, since merely empirical grounds of proof lead to nothing supersensible, and since what is lacking in the series of them cannot in any way be completed, we do not approach in the least nearer in our attempt to attain by their means to the supersensible and to a cognition thereof. Thus in any judgement about the latter by means of arguments derived from experience, probability has no place.
(4.) If an _hypothesis_ is to serve for the explanation of the possibility of a given phenomenon, at least its possibility must be completely certain.[143] It is sufficient that in an hypothesis I disclaim any cognition of actuality (which is claimed in an opinion given out as probable); more than this I cannot give up. The possibility of that which I place at the basis of my explanation, must at least be exposed to no doubt; otherwise there would be no end of empty chimeras. But to assume the possibility of a supersensible Being determined according to certain concepts would be a completely groundless supposition. For here none of the conditions requisite for cognition, as regards that in it which rests upon intuition, is given, and so the sole criterion of possibility remaining is the mere principle of Contradiction (which can only prove the possibility of the thought, not of the object thought).
The result then is this. For the existence [Dasein] of the original Being, as a Godhead, or of the soul as an immortal spirit, absolutely no proof in a theoretical point of view is possible for the human Reason, which can bring about even the least degree of belief. The ground of this is quite easy to comprehend. For determining our Ideas of the supersensible we have no material whatever, and we must derive this latter from things in the world of sense, which is absolutely inadequate for such an Object. Thus, in the absence of all determination of it, nothing remains but the concept of a non-sensible something which contains the ultimate ground of the world of sense, but which does not furnish any knowledge (any amplification of the concept) of its inner constitution.
§ 91. _Of the kind of belief produced by a practical faith_ If we look merely to the way in which anything can be _for us_ (according to the subjective constitution of our representative powers) an Object of knowledge (_res cognoscibilis_), then our concepts will not cohere with Objects, but merely with our cognitive faculties and the use which they can make of a given representation (in a theoretical or practical point of view). Thus the question whether anything is or is not a cognisable being is not a question concerning the possibility of things but of our knowledge of them.
_Cognisable_ things are of three kinds: _things of opinion_ (_mere credibile_).
(1.) Objects of mere rational Ideas, which for theoretical knowledge cannot be presented in any possible experience, are so far not _cognisable_ things, and consequently in respect of them we can form no _opinion_; for to form an opinion _a priori_ is absurd in itself and the straight road to mere chimeras. Either then our proposition is certain _a priori_ or it contains nothing for belief. Therefore _things of opinion_ are always Objects of an empirical cognition at least possible in itself (objects of the world of sense); but, which, on account merely of the [low] degree of this faculty that we possess, is _for us_ impossible. Thus the ether of the new physicists,[144] an elastic fluid pervading all other matter (mingled intimately with it) is a mere thing of opinion, yet is such that, if our external senses were sharpened to the highest degree, it could be perceived; though it can never be presented in any observation or experiment.
To assume [the existence of] rational inhabitants of other planets is a thing of opinion; for if we could come closer to them, which is in itself possible, we should decide by experience whether they did or did not exist; but as we shall never come so near, it remains in the region of opinion. But to hold the opinion that there are in the material universe pure thinking spirits without bodies (viz. if we dismiss as unworthy of our notice certain phenomena which have been published as actual[145]) is to be called poetic fiction. This is no thing of opinion, but a mere Idea which remains over, when we remove from a thinking being everything material, and only leave thought to it. Whether then the latter (which we know only in man, that is, in combination with a body) does survive, we cannot decide. Such a _rational being_ (_ens rationis ratiocinatae_)[146]; of which latter it is possible to show conclusively, the objective reality of its concept; at least for the practical use of Reason, because this which has its peculiar and apodictically certain principles _a priori_, demands (postulates) it.
(2.) Objects for concepts, whose objective reality can be proved (whether through pure Reason or through experience, and, in the first case, from its theoretical or practical data, in all cases by means of a corresponding intuition) are _things of fact_ (_res facti_).[147] Of this kind are the mathematical properties of magnitudes (in geometry), because they are susceptible of a _presentation a priori_ for the theoretical use of Reason. Further, things or their characteristics, which can be exhibited in experience (either our own or that of others through the medium of testimony) are likewise things of fact.--And, what is very remarkable, there is one rational Idea (susceptible in itself of no presentation in intuition, and consequently, of no theoretical proof of its possibility) which also comes under things of fact. This is the Idea of _freedom_, whose reality, regarded as that of a particular kind of causality (of which the concept, theoretically considered, would be transcendent), may be exhibited by means of practical laws of pure Reason, and conformably to this, in actual actions, and, consequently, in experience.--This is the only one of all the Ideas of pure Reason, whose object is a thing of fact, and to be reckoned under the _scibilia_.
(3.) Objects, which in reference to the use of pure practical Reason that is in conformity with duty must be thought _a priori_ (whether as consequences or as grounds), but which are transcendent for its theoretical use, are mere _things of faith_. Of this kind is the _highest good_ in the world, to be brought about by freedom.[148] The concept of this cannot be established as regards its objective reality in any experience possible for us and thus adequately for the theoretical use of Reason; but its use is commanded by practical pure Reason [in reference to the best possible working out of that purpose],[149] and it consequently must be assumed possible. This commanded effect, _together with the only conditions of its possibility thinkable by us_, viz. the Being of God and the immortality of the soul, are _things of faith_ (_res fidei_), and of all objects are the only ones which can be so called.[150] For though what we learn by _testimony_ from the experience of others must be believed by us, yet it is not therefore a thing of faith; for it was the proper experience of some _one_ witness and so a thing of fact, or is presupposed as such. Again it must be possible by this path (that of historical faith) to arrive at knowledge; and the Objects of history and geography, like everything in general which it is at least possible to know by the constitution of our cognitive faculties, belong not to things of faith but to things of fact. It is only objects of pure Reason which can be things of faith at all, though not as objects of the mere pure speculative Reason: for then they could not be reckoned with certainty among things, _i.e._ Objects of that cognition which is possible for us. They are Ideas, _i.e._ concepts of the objective reality of which we cannot theoretically be certain. On the other hand, the highest final purpose to be worked out by us, by which alone we can become worthy of being ourselves the final purpose of creation, is an Idea which has in a practical reference objective reality for us, and is also a thing. But because we cannot furnish such reality to this concept in a theoretical point of view, it is a mere thing of faith of the pure Reason, along with God and Immortality, as the conditions under which alone we, in accordance with the constitution of our (human) Reason, can conceive the possibility of that effect of the use of our freedom in conformity with law. But belief in things of faith is a belief in a pure practical point of view, _i.e._ a moral faith, which proves nothing for theoretical pure rational cognition, but only for that which is practical and directed to the fulfilment of its duties; it in no way extends speculation or the practical rules of prudence in accordance with the principle of self-love. If the supreme principle of all moral laws is a postulate, so is also the possibility of its highest Object; and consequently, too, the condition under which we can think this possibility is postulated along with it and by it.
Thus the cognition of the latter is neither knowledge nor opinion of the being and character of these conditions, regarded as theoretical cognition; but is a mere assumption in a reference which is practical and commanded for the moral use of our Reason.
If we were able also plausibly to base upon the purposes of nature, which physical Teleology presents to us in such rich abundance, a _determinate_ concept of an intelligent World-Cause, then the existence [Dasein] of this Being would not be a thing of faith. For since this would not be assumed on behalf of the performance of my duty, but only in reference to the explanation of nature, it would be merely the opinion and hypothesis most conformable to our Reason. Now such Teleology leads in no way to a determinate concept of God; on the contrary, this can only be found in the concept of a moral Author of the World, because this alone furnishes the final purpose to which we can only reckon ourselves [as attached] if we behave conformably to what the moral law prescribes as final purpose and consequently obliges us [to do]. Hence it is only by its reference to the Object of our duty, as the condition of the possibility of attaining the final purpose of the same, that the concept of God attains the privilege of counting as a thing of faith, in our belief; but on the other hand, this same concept cannot make its Object valid as a thing of fact. For, although the necessity of duty is very plain for practical Reason, yet the attainment of its final purpose, so far as it is not altogether in our own power, is only assumed on behalf of the practical use of Reason, and therefore is not so practically necessary as duty itself.[151] _Faith_ (as _habitus_, not as _actus_) is the moral attitude of Reason as to belief in that which is unattainable by theoretical cognition.
It is therefore the constant principle of the mind, to assume as true, on account of the obligation in reference to it, that which it is necessary to presuppose as condition of the possibility of the highest moral final purpose[152]; although its possibility or impossibility be alike impossible for us to see into. Faith (absolutely so called) is trust in the attainment of a design, the promotion of which is a duty, but the possibility of the fulfilment of which (and consequently also that of the only conditions of it thinkable by us) is not to be _comprehended_ by us. Faith, then, that refers to particular objects, which are not objects of possible knowledge or opinion (in which latter case it ought to be called, especially in historical matters, credulity and not faith), is quite moral. It is a free belief, not in that for which dogmatical proofs for the theoretically determinant Judgement are to be found, or in that to which we hold ourselves bound, but in that which we assume on behalf of a design in accordance with laws of freedom. This, however, is not, like opinion, without any adequate ground; but, is grounded as in Reason (although only in respect of its practical employment), and _adequately for its design_. For without this, the moral attitude of thought in its repudiation of the claim of the theoretical Reason for proofs (of the possibility of the Objects of morality) has no permanence; but wavers between practical commands and theoretical doubts. To be _incredulous_ means to cling to maxims, and not to believe testimony in general; but he is _unbelieving_, who denies all validity to rational Ideas, because there is wanting a _theoretical_ ground of their reality.[154] He judges therefore dogmatically. A dogmatical _unbelief_ cannot subsist together with a moral maxim dominant in the mental attitude (for Reason cannot command one to follow a purpose, which is cognised as nothing more than a chimera); but a _doubtful faith_ can. To this the absence of conviction by grounds of speculative Reason is only a hindrance, the influence of which upon conduct a critical insight into the limits of this faculty can remove, while it substitutes by way of compensation a paramount practical belief.
* * * * * If, in place of certain mistaken attempts, we wish to introduce a different principle into philosophy and to promote its influence, it makes us highly contented to see how and why those attempts must have disappointed us.
_God_, _freedom_, and _immortality_, are the problems at the solution of which all the equipments of Metaphysic aim, as their ultimate and unique purpose. Now it was believed that the doctrine of freedom is needed for practical philosophy only as its negative condition; but that on the other hand the doctrine of God and of the constitution of the soul, as belonging to theoretical philosophy, must be established for themselves and separately, in order afterwards to unite both with that which the moral law (possible only under the condition of freedom) commands, and so to constitute a religion. But we can easily see that these attempts must fail. For from mere ontological concepts of things in general, or of the existence of a necessary Being, it is possible to form absolutely no determinate concept of an original Being by means of predicates which can be given in experience and can therefore serve for cognition. Again a concept based on experience of the physical purposiveness of nature could furnish no adequate proof for morality, or consequently for cognition of a Deity. Just as little could the cognition of the soul by means of experience (which we only apply in this life) supply us with a concept of its spiritual immortal nature, a concept which would be adequate for morality. _Theology_ and _Pneumatology_, regarded as problems of the sciences of a speculative Reason, can be established by no empirical data and predicates, because the concept of them is transcendent for our whole cognitive faculty.--The determination of both concepts, God and the soul (in respect of its immortality) alike, can only take place by means of predicates, which, although they are only possible from a supersensible ground, must yet prove their reality in experience; for thus alone can they make possible a cognition of a quite supersensible Being.--The only concept of this kind to be met with in human Reason is that of the freedom of men under moral laws, along with the final purpose which Reason prescribes by these laws. Of these two [the moral laws and the final purpose] the first are useful for ascribing to the Author of Nature, the second for ascribing to man, those properties which contain the necessary condition of the possibility of both [God and the soul]; so that from this Idea a conclusion can be drawn as to the existence and constitution of these beings which are otherwise quite hidden from us.
Thus the ground of the failure of the attempt to prove God and immortality by the merely theoretical path lies in this, that no cognition whatever is possible of the supersensible in this way (of natural concepts). The ground of its success by the moral way (of the concept of freedom) is as follows. Here the supersensible (freedom), which in this case is fundamental, by a determinate law of causality that springs from it, not only supplies material for cognition of other supersensibles (the moral final purpose and the conditions of its attainability), but also establishes its reality in actions as a fact; though at the same time it can furnish a valid ground of proof in no other than a practical point of view (the only one, however, of which Religion has need).
It is thus very remarkable that of the three pure rational Ideas, _God_, _freedom_, and _immortality_, that of freedom is the only concept of the supersensible which (by means of the causality that is thought in it) proves its objective reality in nature by means of the effects it can produce there; and thus renders possible the connexion of both the others with nature, and of all three together with Religion. We have therefore in us a principle capable of determining the Idea of the supersensible within us, and thus also that of the supersensible without us, for knowledge, although only in a practical point of view; a principle this of which mere speculative philosophy (which could give a merely negative concept of freedom) must despair.
Consequently the concept of freedom (as fundamental concept of all unconditioned practical laws) can extend Reason beyond those bounds, within which every natural (theoretical) concept must remain hopelessly limited.
_General remark on Teleology_ If the question is, what rank the moral argument, which proves the Being of God only as a thing of faith for the practical pure Reason, maintains among the other arguments in philosophy, it is easy to set aside the whole achievement of this last; by which it appears that there is no choice, but that our theoretical faculty must give up all its pretensions before an impartial criticism.
All belief must in the first place be grounded upon facts, if it is not to be completely groundless; and therefore the only distinction in proofs that there can be is that belief in the consequence derived therefrom can either be grounded on this fact as _knowledge_ for theoretical cognition, or merely as _faith_ for practical. All facts belong either to the _natural concept_ which proves its reality in the objects of sense, given (or which may possibly be given) before all natural concepts; or to the _concept of freedom_, which sufficiently establishes its reality through the causality of Reason in regard of certain effects in the world of sense, possible through it, which it incontrovertibly postulates in the moral law. The natural concept (merely belonging to theoretical cognition) is now either metaphysical and thinkable completely _a priori_, or physical, _i.e._ thinkable _a posteriori_ and as necessary only through determinate experience.
The metaphysical natural concept (which presupposes no determinate experience) is therefore ontological.
The _ontological_ proof of the being of God from the concept of an original Being is either that which from ontological predicates, by which alone it can be thought as completely determined, infers absolutely necessary being; or that which, from the absolute necessity of the being somewhere of some thing, whatever it be, infers the predicates of the original Being. For there belongs to the concept of an original Being, inasmuch as it is not derived from anything, the unconditioned necessity of its presence, and (in order to represent this) its complete determination by its [mere][155] concept. It was believed that both requirements were found in the concept of the ontological Idea of a _Being the most real of all_; and thus two metaphysical proofs originated.
The proof (properly called ontological) resting upon a merely metaphysical natural concept concludes from the concept of the Being the most real of all, its absolutely necessary existence; for (it is said), if it did not exist, a reality would be wanting to it, viz. existence.--The other (which is also called the metaphysico-_cosmological_ proof) concludes from the necessity of the existence somewhere of a thing (which must be conceded, for a being is given to us in self-consciousness), its complete determination as that of a Being the most real of all; for everything existing must be completely determined, but the absolutely necessary (_i.e._ that which _we_ ought to cognise as such and consequently _a priori_) must be completely determined _by means of its own concept_. But this is only the case with the concept of a thing the most real of all. It is not needful to expose here the sophistry in both arguments, which has been already done elsewhere;[156] it is only needful to remark that neither proof, even if they could be defended by all manner of dialectical subtlety, could ever pass from the schools into the world, or have the slightest influence on the mere sound Understanding.
The proof, which rests on a natural concept that can only be empirical and yet is to lead us beyond the bounds of nature regarded as the complex of the objects of sense, can be no other than that derived from the _purposes_ of nature. The concept of these cannot, it is true, be given _a priori_ but only through experience; but yet it promises such a concept of the original ground of nature as alone, among all those which we can conceive, is suited to the supersensible, viz. that of a highest Understanding as Cause of the world. This, in fact, it completely performs in accordance with principles of the reflective Judgement, _i.e._ in accordance with the constitution of our (human) faculty of cognition.--But whether or not it is in a position to supply from the same data this concept of a _supreme_, _i.e._ independent intelligent Being, in short of a God or Author of a world under moral laws, and consequently as sufficiently determined for the Idea of a final purpose of the being of the world--this is the question upon which everything depends, whether we desire a theoretically adequate concept of the Original Being on behalf of our whole knowledge of nature, or a practical concept for religion.
This argument derived from physical Teleology is worthy of respect. It produces a similar effect in the way of conviction upon the common Understanding as upon the subtlest thinker; and a _Reimarus_[157] has acquired immortal honour in his work (not yet superseded), in which he abundantly develops this ground of proof with his peculiar thoroughness and lucidity.--But how does this proof acquire such mighty influence upon the mind? How does a judgement by cold reason (for we might refer to persuasion the emotion and elevation of reason produced by the wonders of nature) issue thus in a calm and unreserved assent? It is not the physical purposes, which all indicate in the World Cause an unfathomable intelligence; these are inadequate thereto, because they do not satisfy the need of the inquiring Reason. For, wherefore (it asks) are all those natural things that exhibit art? Wherefore is man himself, whom we must regard as the ultimate purpose of nature thinkable by us? Wherefore is this collective Nature here, and what is the final purpose of such great and manifold art? Reason cannot be contented with enjoyment or with contemplation, observation, and admiration (which, if it stops there, is only enjoyment of a particular kind) as the ultimate final purpose for the creation of the world and of man himself; for this presupposes a personal worth, which man alone can give himself, as the condition under which alone he and his being can be the final purpose. Failing this (which alone is susceptible of a definite concept), the purposes of nature do not satisfactorily answer our questions; especially because they cannot furnish any _determinate_ concept of the highest Being as an all-sufficient (and therefore unique and so properly called _highest_) being, and of the laws according to which an Understanding is Cause of the world.
Hence that the physico-teleological proof convinces, just as if it were a theological proof, does not arise from our availing ourselves of the Ideas of purposes of nature as so many empirical grounds of proof of a _highest_ Understanding. But it mingles itself unnoticed with that moral ground of proof, which dwells in every man and influences him secretly, in the conclusion by which we ascribe to the Being, which manifests itself with such incomprehensible art in the purposes of nature, a final purpose and consequently wisdom (without however being justified in doing so by the perception of the former); and by which therefore we arbitrarily fill up the lacunas of the [design] argument.
In fact it is only the moral ground of proof which produces conviction, and that only in a moral reference with which every man feels inwardly his agreement. But the physico-teleological proof has only the merit of leading the mind, in its consideration of the world, by the way of purposes and through them to an _intelligent_ Author of the world. The moral reference to purposes and the Idea of a moral legislator and Author of the world, as a theological concept, seem to be developed of themselves out of that ground of proof, although they are in truth pure additions.
Henceforward we may allow the customary statement to stand. For it is generally difficult (if the distinction requires much reflection) for ordinary sound Understanding to distinguish from one another as heterogeneous the different principles which it confuses, and from one of which alone it actually draws conclusions with correctness. The moral ground of proof of the Being of God, properly speaking, does not merely _complete_ and render perfect the physico-teleological proof; but it is a special proof that _supplies_ the conviction which is wanting in the latter. This latter in fact can do nothing more than guide Reason, in its judgements upon the ground of nature and that contingent but admirable order of nature only known to us by experience, to the causality of a Cause containing the ground of the same in accordance with purposes (which we by the constitution of our cognitive faculties must think as an intelligent cause); and thus by arresting the attention of Reason it makes it more susceptible of the moral proof. For what is requisite to the latter concept is so essentially different from everything which natural concepts contain and can teach, that there is need of a particular ground of proof quite independent of the former, in order to supply the concept of the original Being adequately for Theology and to infer its existence.--The moral proof (which it is true only proves the Being of God in a practical though indispensable aspect of Reason) would preserve all its force, if we found in the world no material, or only that which is doubtful, for physical Teleology. It is possible to conceive rational beings surrounded by a nature which displayed no clear trace of organisation but only the effects of a mere mechanism of crude matter; on behalf of which and amid the changeability of some merely contingent purposive forms and relations there would appear to be no ground for inferring an intelligent Author. In such case there would be no occasion for a physical Teleology; and yet Reason, which here gets no guidance from natural concepts, would find in the concept of freedom and in the moral Ideas founded thereon a practically sufficient ground for postulating the concept of the original Being in conformity with these, _i.e._ as a Deity, and for postulating nature (even the nature of our own being) as a final purpose in accordance with freedom and its laws--and all this in reference to the indispensable command of practical Reason.--However the fact that there is in the actual world for the rational beings in it abundant material for physical Teleology (even though this is not necessary) serves as a desirable confirmation of the moral argument, as far as nature can exhibit anything analogous to the (moral) rational Ideas. For the concept of a supreme Cause possessing intelligence (though not reaching far enough for a Theology) thus acquires sufficient reality for the reflective Judgement, but it is not required as the basis of the moral proof; nor does this latter serve to complete as a proof the former, which does not by itself point to morality at all, by means of an argument developed according to a single principle. Two such heterogeneous principles as nature and freedom can only furnish two different kinds of proof; and the attempt to derive one from the other is found unavailing as regards that which is to be proved.
If the physico-teleological ground of proof sufficed for the proof which is sought, it would be very satisfactory for the speculative Reason; for it would furnish the hope of founding a Theosophy (for so we must call the theoretical cognition of the divine nature and its existence which would suffice at once for the explanation of the constitution of the world and for the determination of moral laws).