Kant's Critique of Judgement · Immanuel Kant
CRITIQUE OF THE TELEOLOGICAL JUDGEMENT
Further, objective purposiveness, as a principle of the possibility of things of nature, is so far removed from _necessary_ connexion with the concept of nature, that it is much oftener precisely that upon which one relies to prove the contingency of nature and of its form. When, _e.g._ we adduce the structure of a bird, the hollowness of its bones, the disposition of its wings for motion and of its tail for steering, _etc._, we say that all this is contingent in the highest degree according to the mere _nexus effectivus_ of nature, without calling in the aid of a particular kind of causality, namely that of purpose (_nexus finalis_). In other words, nature, considered as mere mechanism, could have produced its forms in a thousand other ways without stumbling upon the unity which is in accordance with such a principle. It is not in the concept of nature but quite apart from it that we can hope to find the least ground _a priori_ for this.
Nevertheless the teleological act of judgement is rightly brought to bear, at least problematically, upon the investigation of nature; but only in order to bring it under principles of observation and inquiry according to the _analogy_ with the causality of purpose, without any pretence to _explain_ it thereby. It belongs therefore to the reflective and not to the determinant judgement. The concept of combinations and forms of nature in accordance with purposes is then at least _one principle more_ for bringing its phenomena under rules where the laws of simply mechanical causality do not suffice. For we bring in a teleological ground, where we attribute causality in respect of an Object to the concept of an Object, as if it were to be found in nature (not in ourselves); or rather when we represent to ourselves the possibility of the Object after the analogy of that causality which we experience in ourselves, and consequently think nature technically as through a special faculty. If we did not ascribe to it such a method of action, its causality would have to be represented as blind mechanism. If, on the contrary, we supply to nature causes acting _designedly_, and consequently place at its basis teleology, not merely as a _regulative_ principle for the mere _judging_ of phenomena, to which nature can be thought as subject in its particular laws, but as a _constitutive_ principle of the _derivation_ of its products from their causes; then would the concept of a natural purpose no longer belong to the reflective but to the determinant Judgement. Then, in fact, it would not belong specially to the Judgement (like the concept of beauty regarded as formal subjective purposiveness), but as a rational concept it would introduce into natural science a new causality, which we only borrow from ourselves and ascribe to other beings, without meaning to assume them to be of the same kind with ourselves.
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