Page:Popular Science Monthly Volume 10.djvu/107

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97
IS DEVELOPMENT HYPOTHESIS SUFFICIENT?

aware, resident in its slender fore and hind legs, which are flexible and elastic levers, capable of being moved by very heavy muscles. And in order to supply the engines that work these levers—the muscles—with the force they expend, the horse is provided with a very perfect feeding apparatus and very perfect digestive apparatus." In all these things being provided—the phrase used by Huxley, though he has no right to use it—there is evidence of purpose, and this is not diminished, but rather increased, by the fact that the animal has been thus perfected by a long descent from an ancient progenitor. The argument of Paley and of the Bridgewater Treatises, derived from the bones and muscles of animals, and from the adjustments in every part of Nature, is as valid and convincing as ever. I believe Prof. Huxley admits this. I discover adaptation and contrivance, not only in the products but in the very process of development. Viewed in this light, development may, in the hands of a new Paley, furnish further and very striking cases of design. For, in order to the success of the process, there is often need of coördinated structure, that is, of a structure in which a number of parts are adapted to each other. My friend Mr. Joseph J. Murphy has supplied us with an instance in the case of the two nervous connections of the iris of the eye. "One of its nerves has its root in the brain, and contracts the pupil under the stimulus of light; the other has its root in the sympathetic ganglia, and opens the pupil again when the intensity of light is diminished. It is obviously impossible that the efficiency of either of these two nerves could be increased separately; they will not be improved at all unless they are improved together; and this, on Darwin's principles, can only be done by means of accidental favorable circumstances occurring in both at once. But such coincidences are so improbable that they may be left out of account as if they were impossible." I do not agree with Mr. Murphy in thinking that such an instance tells against Darwin; but I think the coincidence shows a preordained arrangement, and such coincidences are found in nearly every case of development, thus showing the need of coöperation and contrivance in the very developing process. It is to be observed that evolution, vegetable and animal, and natural selection, are not simple properties of matter like gravitation and chemical affinity. They imply the concurrence of an immense number of agents, mechanical, chemical, electric, galvanic; and Darwin adds pangenesis, and Spencer physiological units. In the concurrence and cooperation of all these to develop the plant and animal, I see proof of purpose; and in the culmination of the whole in the perfect forms of the higher animated beings, I discover a guiding intelligence which designed the end from the beginning.

4. There are Typical Forms in Nature.—It is now twenty years since, in conjunction with Dr. Dickie, I wrote "Typical Forms and Special Ends in Creation," in which I showed that there was not