THREE:At this point will occur one of those mechanical problems which requires what may be called logical solution. The valve must be moved by the drop; there is no other moving mechanism available; the valve and drop must besides be connected, to insure coincident action, yet the valve requires to move when the drop is still. Proceeding inductively, it is clear that a third agent must be introduced, some part moved by the drop, which will in turn move the valve, but this intermediate agent so arranged that it may continue to move after the hammer-drop has stopped.All these, however, are mere questions of detail. It is on a subject of the profoundest philosophical importance that Aristotle differs most consciously, most radically, and most fatally from his predecessors. They were evolutionists, and he was a stationarist. They were mechanicists, and he was a teleologist. They were uniformitarians, and he was a dualist. It is true that, as we mentioned at the beginning of this chapter, Mr. Edwin Wallace makes him recognise the genesis of things by evolution and development, but the meaning of this phrase requires to be cleared up. In one sense it is, of course, almost an identical proposition. The genesis of things must be by genesis of some kind or other. The great question is, what things have been evolved, and how have they been evolved? Modern science tells us, that not only have all particular aggregates of matter and motion now existing come into being within a finite period of time, but also that the specific types under which we arrange those aggregates have equally been generated; and that their characteristics, whether structural or functional, can only be understood by tracing out their origin and history. And it further teaches us that the properties of every aggregate result from the properties of its ultimate elements, which, within the limits of our experience, remain absolutely unchanged. Now, Aristotle taught very nearly the contrary of all this. He believed that the cosmos, as we now know it, had existed, and would continue to exist, unchanged through all eternity. The sun, moon, planets, and stars, together with the orbs containing them, are composed of an absolutely ungenerable, incorruptible substance. The earth, a cold, heavy, solid sphere, though liable to superficial changes, has always occupied its present position in the centre of the universe.317 The specific forms of animal lifeexcept a few which are produced spontaneouslyhave, in like manner, been preserved unaltered through an infinite series of generations. Man shares the common lot. There is no continuous progress of civilisation. Every invention and discovery has been made and lost an infinite number of times. Our philosopher could not, of course, deny that individual living things come into existence and gradually grow to maturity; but he insists that their formation is teleologically determined by the parental type which they are striving to realise. He asks whether we should study a thing by examining how it grows, or by examining its completed form: and Mr. Wallace quotes the question without quoting the answer.203 Aristotle tells us that the genetic method was followed by his predecessors, but that the other method is his. And he goes on to censure Empedocles for saying that many things in the animal body are due simply to mechanical causation; for example, the segmented structure of the backbone, which that philosopher attributes to continued doubling and twistingthe very same explanation, we believe, that would be given of it by a modern evolutionist.204 Finally, Aristotle assumes the only sort of transformation which we deny, and which Democritus equally deniedthat is to say, the transformation of the ultimate elements into one another by the oscillation of an indeterminate matter between opposite qualities.
One morning, when Gregor Samsa woke from troubled dreams
