What the things in the world are mutually useful for; what good the manifold in a thing does for the thing; how we have ground to assume that nothing in the world is in vain, but that everything in nature is good for something,—the condition being granted that certain things are to exist (as purposes), whence our Reason has in its power for the Judgement no other principle of the possibility of the Object, which it inevitably judges teleologically, than that of subordinating the mechanism of nature to the Architectonic of an intelligent Author of the world—all this the teleological consideration of the world supplies us with excellently and to our extreme admiration. But because the data, and so the principles, for determining that concept of an intelligent World Cause (as highest artist) are merely empirical, they do not enable us to infer any of its properties beyond those which experience reveals in its effects. Now experience, since it can never embrace collective nature as a system, must often (apparently) happen upon this concept (and by mutually conflicting grounds of proof); but it can never, even if we had the power of surveying empirically the whole system as far as it concerns mere nature, raise us above nature to the purpose of its existence, and so to the determinate concept of that supreme Intelligence.
If we lessen the problem with the solution of which Physico-theology has to do, its solution appears easy. If we reduce the concept of a Deity to that of an intelligent being thought by us, of which there may be one or more, which possesses many and very great properties, but not all the properties which are requisite for the foundation of a nature in harmony with the greatest possible purpose; or if we do not scruple in a theory to supply by arbitrary additions what is deficient in the grounds of proof, and so, where we have only ground for assuming much perfection (and what is “much” for us?), consider ourselves entitled to presuppose all possible perfection; thus indeed physical Teleology may make weighty claims to the distinction of being the basis of a Theology. But if we are desired to point out what impels and moreover authorises us to add these supplements, then we shall seek in vain for a ground of justification in the principles of the theoretical use of Reason, which is ever desirous in the explanation of an Object of experience to ascribe to it no more properties than those for which empirical data of possibility are to be found. On closer examination we should see that properly speaking an Idea of a Supreme Being, which rests on a quite different use of Reason (the practical use), lies in us fundamentally a priori, impelling us to supplement, by the concept of a Deity, the defective representation, supplied by a physical Teleology, of the original ground of the purposes in nature; and we should not falsely imagine that we had worked out this Idea, and with it a Theology by means of the theoretical use of Reason in the physical cognition of the world—much less that we had proved its reality.
One cannot blame the ancients much, if they thought of their gods as differing much from each other both as regards their faculties and as regards their designs and volitions, but yet thought of all of them, the Supreme One not excepted, as always limited after human fashion. For if they considered the arrangement and the course of things in nature, they certainly found ground enough for assuming something more than mechanism as its cause, and for conjecturing behind the machinery of this world designs of certain higher causes, which they could not think otherwise than superhuman. But because they met with good and evil, the purposive and the unpurposive, mingled together (at least as far as our insight goes), and could not permit themselves to assume nevertheless that wise and benevolent purposes of which they saw no proof lay hidden at bottom, on behalf of the arbitrary Idea of a supremely perfect original Author, their judgement upon the supreme World Cause could hardly have been other than it was, so long as they proceeded consistently according to maxims of the mere theoretical use of Reason. Others, who wished to be theologians as well as physicists, thought to find contentment for the Reason by providing for the absolute unity of the principle of natural things which Reason demands, the Idea of a Being of which as sole Substance the things would be all only inherent determinations. This Substance would not be Cause of the World by means of intelligence, but in it all the intelligences of the beings in the world would be comprised. This Being consequently would produce nothing according to purposes; but in it all things, on account of the unity of the subject of which they are mere determinations, must necessarily relate themselves purposively to one another, though without purpose and design. Thus they introduced the Idealism of final causes, by changing the unity (so difficult to explain) of a number of purposively combined substances, from being the unity of causal dependence on one Substance to be the unity of inherence in one. This system—which in the sequel, considered on the side of the inherent world beings, becomes Pantheism, and (later) on the side of the Subject subsisting by itself as Original Being, becomes Spinozism,—does not so much resolve as explain away into nothing the question of the first ground of the purposiveness of nature; because this latter concept, bereft of all reality, must be taken for a mere misinterpretation of a universal ontological concept of a thing in general.
Hence the concept of a Deity, which would be adequate for our teleological judging of nature, can never be derived from mere theoretical principles of the use of Reason (on which Physico-theology alone is based). For as one alternative we may explain all Teleology as a mere deception of the Judgement in its judging of the causal combination of things, and fly to the sole principle of a mere mechanism of nature, which merely seems to us, on account of the unity of the Substance of whose determinations nature is but the manifold, to contain a universal reference to purposes. Or if, instead of this Idealism of final causes, we wish to remain attached to the principle of the Realism of this particular kind of causality, we may set beneath natural purposes many intelligent original beings or only a single one. But so far as we have for the basis of this concept [of Realism] only empirical principles derived from the actual purposive combination in the world, we cannot on the one hand find any remedy for the discordance that nature presents in many examples in respect of unity of purpose; and on the other hand, as to the concept of a single intelligent Cause, so far as we are authorised by mere experience, we can never draw it therefrom in a manner sufficiently determined for any serviceable Theology whatever (whether theoretical or practical).
Physical Teleology impels us, it is true, to seek a Theology; but it cannot produce one, however far we may investigate nature by means of experience and, in reference to the purposive combination apparent in it, call in Ideas of Reason (which must be theoretical for physical problems). What is the use, one might well complain, of placing at the basis of all these arrangements a great Understanding incommensurable by us, and supposing it to govern the world according to design, if nature does not and cannot tell us anything of the final design? For without this we cannot refer all these natural purposes to any common point, nor can we form any teleological principle, sufficient either for cognising the purposes collected in a system, or for forming a concept of the Supreme Understanding, as Cause of such a nature, that could serve as a standard for our Judgement reflecting teleologically thereon. I should thus have an artistic Understanding for scattered purposes, but no Wisdom for a final purpose, in which final purpose nevertheless must be contained the determining ground of the said Understanding. But in the absence of a final purpose which pure Reason alone can supply (because all purposes in the world are empirically conditioned, and can contain nothing absolutely good but only what is good for this or that regarded as a contingent design), and which alone would teach me what properties, what degree, and what relation of the Supreme Cause to nature I have to think in order to judge of nature as a teleological system; how and with what right do I dare to extend at pleasure my very limited concept of that original Understanding (which I can base on my limited knowledge of the world), of the Might of that original Being in actualising its Ideas, and of its Will to do so, and complete this into the Idea of an Allwise, Infinite Being? If this is to be done theoretically, it would presuppose omniscience in me, in order to see into the purposes of nature in their whole connexion, and in addition the power of conceiving all possible plans, in comparison with which the present plan would be judged on [sufficient] grounds as the best. For without this complete knowledge of the effect I can arrive at no determinate concept of the Supreme Cause, which can only be found in the concept of an Intelligence infinite in every respect, i.e. the concept of a Deity, and so I can supply no foundation for Theology.
Hence, with every possible extension of physical Teleology, according to the propositions above laid down we may say: By the constitution and the principles of our cognitive faculty we can think of nature, in its purposive arrangements which have become known to us, in no other way than as the product of an Understanding to which it is subject. But the theoretical investigation of nature can never reveal to us whether this Understanding may not also, with the whole of nature and its production, have had a final design (which would not lie in the nature of the sensible world). On the contrary, with all our knowledge of nature it remains undecided whether that Supreme Cause is its original ground according to a final purpose, or not rather by means of an Understanding determined by the mere necessity of its nature to produce certain forms (according to the analogy of what we call the art-instinct in animals); without it being necessary to ascribe to it even wisdom, much less the highest wisdom combined with all other properties requisite for the perfection of its product.
Hence Physico-theology is a misunderstood physical Teleology, only serviceable as a preparation (propaedeutic) for Theology; and it is only adequate to this design by the aid of a foreign principle on which it can rely, and not in itself, as its name would intimate.
§ 86. Of Ethico-theology
The commonest Understanding, if it thinks over the presence of things in the world, and the existence of the world itself, cannot forbear from the judgement that all the various creatures, no matter how great the art displayed in their arrangement, and how various their purposive mutual connexion,—even the complex of their numerous systems (which we incorrectly call worlds),—would be for nothing, if there were not also men (rational beings in general). Without men the whole creation would be a mere waste, in vain, and without final purpose. But it is not in reference to man’s cognitive faculty (theoretical Reason) that the being of everything else in the world gets its worth; he is not there merely that there may be some one to contemplate the world. For if the contemplation of the world only afforded a representation of things without any final purpose, no worth could accrue to its being from the mere fact that it is known; we must presuppose for it a final purpose, in reference to which its contemplation itself has worth. Again it is not in reference to the feeling of pleasure, or to the sum of pleasures, that we think a final purpose of creation as given; i.e. we do not estimate that absolute worth by well-being or by enjoyment (whether bodily or mental), or in a word, by happiness. For the fact that man, if he exists, takes this for his final design, gives us no concept as to why in general he should exist, and as to what worth he has in himself to make his existence pleasant. He must, therefore, be supposed to be the final purpose of creation, in order to have a rational ground for holding that nature must harmonise with his happiness, if it is considered as an absolute whole according to principles of purposes.—Hence there remains only the faculty of desire; not, however, that which makes man dependent (through sensuous impulses) upon nature, nor that in respect of which the worth of his being depends upon what he receives and enjoys. But the worth which he alone can give to himself, and which consists in what he does, how and according to what principles he acts, and that not as a link in nature’s chain but in the freedom of his faculty of desire—i.e. a good will—is that whereby alone his being can have an absolute worth, and in reference to which the being of the world can have a final purpose.