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and leads us to inquire the reason why. We reply that the

. eye was made to see. This reason is needed to account for all phenomena that appear designed to accomplish definite results. The why, in distinction from the how, is named the mental, subjective, or final cause.

Some object to this reason, saying that for cause it puts effect. It is not the effect, however, but the idea of that effect, which constitutes the final cause. This idea precedes, but does not supplant, efficient agency.

Efficient causes are the means which realize objectively what has first been ideally conceived, -just as man, before constructing a machine to accomplish a purpose, has that purpose in mind. This determination of the present to the future is the distinctive element of finality. To explain any adaptation, truth requires a spiritual as well as material factor. The two causes are complementary and bar. monious.

Design possesses the same basis of fact as the natural systems of organic science. Homology expresses the fact that in nature there are serial relations, correspondences in type of structure, an example of which is the unity of type exhibited in a fish's pectoral fin, a bird's wing, a dog's fore-leg, a man's arm. Because of bis knowledge of ichthyic relations, Mr. Agassiz was enabled to delineate from a single part, correctly as it proved, the skeleton of the fish from which it was taken. The reconstruction from a single part shows mutual adaptations in every portion of the skeleton. Homology, or the study of relations, the basis of all comparative science, finds expression in natural classification, the statement of those relations. Though homologies are but relations they are facts as shown by the instance given. Although classification is but a statement of relations it is an accepted scientific principle,, a practical rule, a truth. Yet it is based only on the perception of relations. If these systematic relations did not actually exist in nature, natural science would be impossible, since it is systematized knowledge.

Now it is on these very same relations, or adaptations of part to part-witness the case cited,-fitted to accomplish an end, which constitutes the induction of design. Resting on the same basis of natural relations are teleology and scientific sys- . terns, alike only perceiyable by intelligence and alike only

conceivable as the result of intelligent manifestations in those relations. Founded on this solid basis of actual relation in nature, Design is correctly termed by Mr. Mill, an inductive argument. As an induction is to be established like any other, by an appeal to the facts concerned, namely, adaptations.

Design is an induction, the value of which depends on the weight of evidence. Design cannot be demonstrated with mathematical certainty. The value of the induction from results which appear purposed depends on the weight of evidence. The presumption in any given case may be small or it may be great. The probability of design is increased by the repetition of results in an individual case, by the multiplication of cases producing like results, by specialization of structure, by uniqueness of function. The more complex and oft-repeated the adaptation of structure to function, instinct to action, species to environment, the greater the evidence of design, until at last it becomes a necessity of thought,-conviction like that which certifies to ideal, serial relations in geology and biology, and without which they would not be sciences but mere aggregations of facts. Probability lesser or greater, according to the ground of the induction, is the only support of scientific theories, and most departments of science considered thoroughly established, are only morally certain theories.

The human eye as an instrument for sight, with its supplementary parts, the complexity of the structure, the marvelous adjustments not only to an external medium, but between the several parts, from early time has been considered to present irrefragable evidence of design. Throughout nature countless adaptations roll up so great a body of evidence that the inducsion of design is not only unanswerable, but any other explanation, circumstances considered, is not conceivable. For in. stances in proof of design, reference is made to Paley, the Bridgewater treatises, and of recent works, to Janet and others. Some of Mr. Darwin's special works, as the Fertilization of Orchids, are capital cases in point. The force of the argument, the means for proving it, are within reach of all. Knowledge of processes is unessential since results—adaptations—are, and always bave been, the facts from which the chiefest evidence is derived. The induction of design has commended itself to the common sense of all generations.

THE THEORY OF DEVELOPMENT. Upon the study of living and fossil organisms, their processes and relations, external and internal, is based the series of inductions embodied in the theory of development. Development is the evolution of organisms by natural process. For ages its principles have been employed by breeder and horticulturist to improve old and originate new varieties. What man does only by working in obedience to natural law, nature accomplishes of itself, environment replacing man as the external factor. A A tendency to vary is part of every organism, and this internal, physiological tendency responds to external change. But environment does not originate variation any more than the canal originates the stream which it directs. Heredity is the fact that offspring resemble parent, variation that they differ from parent. The efficient causes of resemblance and variation are unknown, save that they are physiological and not physical, dynamic and not mechanical.

Overproduction expresses the observation that many more individuals are produced than there is food or room for; hence arises a struggle for existence in which the weaker individuals perish and the stronger survive. This is the survival of the fittest or natural selection. The survival results because of greater ability to cope with and conquer adverse conditions of existence. This natural selection by which organisms are brought into harmony with environment is a negative result, since it operates only by suppressing weaker individuals. Thus each generation propagates from its best and each becomes more perfect than the preceding, just as in producing the race. horse, man selected the fleetest horses and bred from them; of

progeny the fleetest were in turn paired, and so on till the present result has been attained. Those results that are per. manently helpful to the individual become developed by use and the variation is transmitted in an intensified form to de. scendants. Functions perfect organs, actions develop instinct, organisms are differentiated and specialized, brought into harmony with their respective surroundings, and species are created. The intermediate varieties, being less strongly char

. acterized—weaker, are for the most part blotted out, and series which once connected species are lost.

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Since the several factors are always operating and environment (climate, amount of food, etc.), is ever and gradually changing, “species” are not fixed but are constantly respond. ing to new conditions. “Species” and “varieties," therefore,

" are relative terms. Species, like individuals, succeed one another in serial lines. Successive ages, geology teaches, have produced increasingly specialized forms. The physical conditions gradually improving, from primal germs through the ages have developed all species past and present, —such is the teaching of the theory. Geographic zoology and botany evidence that species are variable and that many intermediate races and varieties now exist. Asa Gray says: “I have been at the making and unmaking of far too many species to retain any overweening confidence in their definiteness and stability. . I believe that they bave only a relative fixity and permanence."

Variation, overproduction, struggle for existence, survival of the fittest—these are the facts of Development. That from primal germs, by increasing specializations and adaptations, has come the present wealth of organic species, is the theory, the series of inductions, based on those facts. It accounts for the greatest number of phenomena, appears eminently reasonable, is compatible with and explains other science, and is accepted by the great body of scientific workers. Like Design it is not strictly demonstrable, but as a matter of induction its probability is so overwhelming that it is considered established.

THE BEARING OF DEVELOPMENT ON TELEOLOGY.

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Accepting the theory of development, what is its bearing upon Design ? Have vegetables and animals “ paved the earth with intentions," as Gray asserts, or is the materialist correct in claiming that in and of itself Development is sufficient to account for all the changes and improvements resulting in present species; that purely natural processes having accounted for adaptations, design is only an appearance?

Nature, they say, is the grand worker, matter and force the two elements of the universe. The eye, for example, is not the result of wise forethought, not an instrument designed for the purpose of seeing. It has become an instrument of vision

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simply and only because light and other external influences operated on the tendency of antecedent ocelli to vary. All adaptations and contrivances are accounted for when their physical antecedents are traced back to their supposed origin. The marvelous correspondence of organ and function no longer exhibit design since environment, directing through ages the tendency to vary, harmonizes them one to another. So with instinct, and with species.

In short, all natural harmonies are only the working of unconscious, unintelligent, impersonal nature. The same system of natural law everywhere pervading the universe causes equally the pebble and the eye. The same immutable law manifested in gravitation falls the stone,-manifested in Development produces the human hand. There is no more intelli- . gence shown in one than the other. The special adaptations of the hand to its uses are not any more available as evidence of design than the adaptations of a river to the bed which it has itself been the means of excavating." Law, immutable law, nothing but law! Briefly, this is the position of the materialist who lays claim to evolution. It is plausible, it has gained more than a limited hearing.

Is it true? Is this the legitimate bearing of Development on teleology? In reply it is said :

Development does not preclude Design. Like all science the theory of development has to do with second or efficient causes, known and unknown. For this reason it cannot account for the beginning of things. Development implies material to be evolved and forces by which it is done, but itself neither orig. inates nor explains that origin. The laws of development do pot account for, but are only manifested in matter by the movements of force. To claim that life is the adjustment of inner to outer relations says nothing, since this adjustment is just what is calling for explanation. Mr. Darwin did not pretend to account for the origin of sensation or life.

Design is not excluded by supposing that Development explains all processes by which adaptations are evolved, even back to the first life-geru. Not accounting when or how materials and forces originated, Development has no reason to give why in those beginnings the factors by which design is

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