The supporters of the concept of purpose believe that, in surrendering it, they are forced to surrender also all unity and order in the world. Listen, for example, to Robert Hamerling (Atomistik des Willens, vol. ii, p. 201): “As long as there are instincts in Nature, so long is it foolish to deny purposes in Nature. Just as the structure of a limb of the human body is not determined and conditioned by an idea of this limb, floating somewhere in mid-air, but by its connection with the more inclusive whole, the body, to which the limb belongs, so the structure of every natural object, be it plant, animal, or man, is not determined and conditioned by an idea of it floating in mid-air, but by the formative principle of the more inclusive whole of Nature which unfolds and organises itself in a purposive manner.” And on page 191 of the same volume we read: “Teleology maintains only that, in spite of the thousand misfits and miseries of this natural life, there is a high degree of adaptation to purpose and plan unmistakable in the formations and developments of Nature—an adaptation, however, which is realised only within the limits of natural laws, and which does not tend to the production of some imaginary fairy-land, in which life would not be confronted by death, growth by decay, with all the more or less unpleasant, but quite unavoidable, intermediary stages between them. When the critics of Teleology oppose a laboriously collected rubbish-heap of partial or complete, imaginary or real, maladaptations to a world full of wonders of purposive adaptation, such as Nature exhibits in all her domains, then I consider this just as amusing——”
What is here meant by purposive adaptation? Nothing but the consonance of percepts within a whole. But, since all percepts are based upon laws (ideas), which we discover by means of thinking, it follows that the orderly coherence of the members of a perceptual whole is nothing more than the ideal (logical) coherence of the members of the ideal whole which is contained in this perceptual whole. To say that an animal or a man is not determined by an idea floating in mid-air is a misleading way of putting it, and the view which the critic attacks loses its apparent absurdity as soon as the phrase is put right. An animal certainly is not determined by an idea floating in mid-air, but it is determined by an idea inborn in it and constituting the law of its nature. It is just because the idea is not external to the natural object, but is operative in it as its very essence, that we cannot speak here of adaptation to purpose. Those who deny that natural objects are determined from without (and it does not matter, in this context, whether it be by an idea floating in mid-air or existing in the mind of a creator of the world), are the very men who ought to admit that such an object is not determined by purpose and plan from without, but by cause and law from within. A machine is produced in accordance with a purpose, if I establish a connection between its parts which is not given in Nature. The purposive character of the combinations which I effect consists just in this, that I embody my idea of the working of the machine in the machine itself. In this way the machine comes into existence as an object of perception embodying a corresponding idea. Natural objects have a very similar character. Whoever calls a thing purposive because its form is in accordance with plan or law may, if he so please, call natural objects also purposive, provided only that he does not confuse this kind of purposiveness with that which belongs to a subjective human action. In order to have a purpose, it is absolutely necessary that the efficient cause should be a concept, more precisely a concept of the effect. But in Nature we can nowhere point to concepts operating as causes. A concept is never anything but the ideal nexus of cause and effect. Causes occur in Nature only in the form of percepts.
Dualism may talk of cosmic and natural purposes. Wherever for our perception there is a nexus of cause and effect according to law, there the Dualist is free to assume that we have but the image of a nexus in which the Absolute has realised its purposes. For Monism, on the other hand, the rejection of an Absolute Reality implies also the rejection of the assumption of purposes in World and Nature.
Addition to the Revised Edition (1918).
No one who, with an open mind, has followed the preceding argument, will come to the conclusion that the author, in rejecting the concept of purpose for extra-human facts, intended to side with those thinkers who reject this concept in order to be able to regard, first, everything outside human action and, next, human action itself, as a purely natural process. Against such misunderstanding the author should be protected by the fact that the process of thinking is in this book represented as a purely spiritual process. The reason for rejecting the concept of purpose even for the spiritual world, so far as it lies outside human action, is that in this world there is revealed something higher than a purpose, such as is realised in human life. And when we characterise as erroneous the attempt to conceive the destiny of the human race as purposive according to the pattern of human purposiveness, we mean that the individual adopts purposes, and that the result of the total activity of humanity is composed of these individual purposes. This result is something higher than its component parts, the purposes of individual men.