We deal with a concept dogmatically (even though it should be empirically conditioned) if we consider it as contained under another concept of the Object which constitutes a principle[113] of Reason, and determine it in conformity with this. But we deal with it merely critically, if we consider it only in reference to our cognitive faculties and consequently to the subjective conditions of thinking it, without undertaking to decide anything about its Object. Dogmatic procedure with a concept is then that which is conformable to law for the determinant Judgement, critical procedure for the reflective Judgement.
Now the concept of a thing as a natural purpose is a concept which subsumes nature under a causality only thinkable through Reason, in order to judge in accordance with this principle about that which is given of the Object in experience. But in order to use it dogmatically for the determinant Judgement, we must be assured first of the objective reality of this concept, because otherwise we could subsume no natural thing under it. Again, the concept of a thing as a natural purpose is, no doubt, empirically conditioned, i.e. only possible under certain conditions given in experience, though not to be abstracted therefrom; but it is a concept only possible in accordance with a rational principle in the judgement about the object. Its objective reality, therefore (i.e. that an object in conformity with it is possible), cannot be comprehended and dogmatically established as such a principle; and we do not know whether it is merely a sophistical and objectively empty concept (conceptus ratiocinans), or a rational concept, establishing a cognition and confirmed by Reason (conceptus ratiocinatus).[114] Therefore it cannot be dogmatically treated for the determinant Judgement, i.e. it is not only impossible to decide whether or not things of nature considered as natural purposes require for their production a causality of a quite peculiar kind (that acting on design); but the question cannot even be put, because the concept of a natural purpose is simply not susceptible of proof through Reason as regards its objective reality. That is, it is not constitutive for the determinant Judgement, but merely regulative for the reflective.
That it is not susceptible of proof is clear because (as concept of a natural product) it embraces in itself natural necessity, and at the same time (as purpose) a contingency of the form of the Object (in reference to the mere laws of nature) in the very same thing. Hence, if there is to be no contradiction here it must contain a ground for the possibility of the thing in nature, and also a ground of the possibility of this nature itself and of its reference to something which, not being empirically cognisable nature (supersensible), is therefore for us not cognisable at all. [This is requisite] if it is to be judged according to a different kind of causality from that of natural mechanism when we wish to establish its possibility. The concept of a thing, then, as a natural purpose, is transcendent for the determinant Judgement, if we consider the Object through Reason (although for the reflective Judgement it certainly may be immanent in respect of the objects of experience). Hence for determinant judgements objective reality cannot be supplied to it; and so it is intelligible how all systems that one may project for the dogmatic treatment of the concept of natural purposes and of nature itself [considered] as a whole connected together by means of final causes, can decide nothing either by objective affirmation or by objective denial. For if things be subsumed under a concept that is merely problematical, its synthetical predicates (e.g. in the question whether the purpose of nature which we conceive for the production of things is designed or undesigned) can furnish only problematical judgements of the Object, whether affirmative or negative; and we do not know whether we are judging about something or about nothing. The concept of a causality through purposes (of art) has at all events objective reality, and also the concept of a causality according to the mechanism of nature. But the concept of a causality of nature according to the rule of purposes,--still more of a Being such as cannot be given us in experience, a Being who is the original cause of nature,--though it can be thought without contradiction, yet is of no avail for dogmatic determinations. For, since it cannot be derived from experience, and also is not requisite for the possibility thereof, its objective reality can in no way be assured. But even if this could be done, how can I number among the products of nature things which are definitely accounted products of divine art, when it is just the incapacity of nature to produce such things according to its own laws that made it necessary to invoke a cause different from it?