A simpler way of putting the case may be to point out that the comparison of a Sensorium is intended, like other similitudes we have reviewed, to hold in only one point. Newton uses it apparently to localize the idea of immediate intuition. In this way all Space, the whole Universe, with its moving contents, which transcend the farthest flight of human imagination are,—not distantly,—but immediately present to the mind of God.
Passing from these thoughts which may illustrate, but cannot explain, a subject dark with excess of splendour, we now enter on a series of extracts so chosen as to furnish an ample examination of the several ideas involved in the philosophy of Design, and an estimate of their several values. It is evidently important that the reader should possess some means of forming clear conceptions respecting the nature of these ideas, and the collection now appended, aims at saving him the trouble of a tedious search. Any points which may have appeared perplexing or obscure in the preceding Chapter will, it is hoped, be made sufficiently plain by a perusal of the following pages.
The first in this class of passages is taken from Whewell's Philosophy of the Inductive Sciences. No one probably was ever much better fitted by training and attainment than that eminent writer for the investigation he here undertakes. We must, however, caution the reader against supposing that Dr. Whewell means to introduce him into a world of Platonism. The ideas he speaks of may be illustrated in this way. Suppose a person constructs a right line according to Euclid's definition and draws it evenly between its extreme points, his mind has immediately an impression of rightness or straightness, which he attaches to all lines actually so constructed or conceived of as theoretically possible. This idea of straightness is absolute and universal. So, again, looking at two such lines, he knows that they, cannot, in the nature of things inclose a space, and this idea likewise is universal and absolutely true.
With the nature of these ideas as a psychological question, the reader need not concern himself for our present purpose. It is sufficient to observe they are brought into activity by a practical occasion. Whether they were wholly or partially pre-existent—or whether they represent a state of our Reason evoked by the occasion—are points which make no difference to their exact strength of validity. We find as a matter of fact in going through life that this particular class of ideas is so very true that it enables us to gauge the material universe. Yet notably enough, Hume in his Treatise (I. 247, seq.) reduces applied mathematics to a species of probability.
Other ideas having various degrees of validity and practical necessity are involved in the diverse processes which pertain to the inductive sciences. Dr. Whewell's work was written for the purpose of elucidating them, which he does at great length. To some such ideas, principles, and beliefs we shall advert by and bye.
All that seems now necessary is to remark that the distinguished author's general division (Book IX.) where our extract will be found, is concerned with the Philosophy of Biology, and that the paragraphs quoted are sections of its chapter VI., "On the Idea of Final Causes."
"1. By an examination of those notions which enter into all our reasonings and judgments on living things, it appears that we conceive animal life as a vortex or cycle of moving matter in which the form of the vortex determines the motions, and these motions again support the form of the vortex: the stationary parts circulate the fluids, and the fluids nourish the permanent parts. Each portion ministers to the others, each depends upon the other. The parts make up the whole, but the existence of the whole is essential to the preservation of the parts. But parts existing under such conditions are organs, and the whole is organized. This is the fundamental conception of organization. 'Organized beings,' says the physiologist,[79] 'are composed of a number of essential and mutually dependent parts.'—'An organized product of nature,' says the great metaphysician,[80] 'is that in which all the parts are mutually ends and means.'
"2. It will be observed that we do not content ourselves with saying that in such a whole, all the parts are mutually dependent. This might be true even of a mechanical structure; it would be easy to imagine a framework in which each part should be necessary to the support of each of the others; for example, an arch of several stones. But in such a structure the parts have no properties which they derive from the whole. They are beams or stones when separate; they are no more when joined. But the same is not the case in an organized whole. The limb of an animal separated from the body, loses the properties of a limb and soon ceases to retain even its form.
"3. Nor do we content ourselves with saying that the parts are mutually causes and effects. This is the case in machinery. In a clock, the pendulum by means of the escapement causes the descent of the weight, the weight by the same escapement keeps up the motion of the pendulum. But things of this kind may happen by accident. Stones slide from a rock down the side of a hill and cause it to be smooth; the smoothness of the slope causes stones still to slide. Yet no one would call such a slide an organized system. The system is organized, when the effects which take place among the parts are essential to our conception of the whole; when the whole would not be a whole, nor the parts, parts, except these effects were produced; when the effects not only happen in fact, but are included in the idea of the object; when they are not only seen, but foreseen; not only expected, but intended: in short when, instead of being causes and effects, they are ends and means, as they are termed in the above definition.