Changing Conditions of the Earth
The grand nebular hypothesis of Laplace came to reinforce the views of the geologists, by showing how the earth itself may have originated as a gaseous or molten globe; and its slow process of cooling, with the reaction of the interior and exterior on each other, served to elucidate the facts of the heated interior, as shown by hot springs and volcanoes, as well as many of the phenomena presented by the distorted and metamorphosed strata which formed its crust. Hence it gradually came to be perceived that the condition of the earth, with all its endless variations of surface, of continents and oceans, of seas and islands, of vast plateaux and lofty mountain ranges and extensive low plains, with their ravines and cataracts, their great lakes and stately rivers, was subject to perpetual change from that remote epoch when it seems to have been actually the case that “the earth was without form and void,” and that owing to the greater density of the vapour-laden atmosphere, “darkness was upon the face of the deep.”
Changing Forms of Life
Another field of geological research forced us to the conclusion that the same continued process of change had affected the forms of life upon the earth. When carefully investigated, the crust was found to abound in the fossilised remains of animals and plants. Careful study of these showed that the oldest of all were of comparatively simple structure, and that the higher forms only appeared in more recent epochs; while the highest of all were probably very little older than man himself. It is only during the last half century that the theory of Evolution has been elaborated and has become generally accepted as applicable to the whole of the vast cosmic process—from the development of the nebulæ into stars and suns and systems, with a corresponding development of planets from an early condition of intense heat, through a more or less lengthy period of cooling and contraction, to an ultimate state of refrigeration, the earlier and later stages being alike unsuited to the existence of life.
Theory of Natural Selection
More important still, the discovery of the theory of Natural Selection by Darwin—and at a later period by myself—has led to a satisfactory explanation of the successive appearance of higher and more complex forms of life, and also of that wonderfully minute and complex adaptation of every species to its conditions of existence and to its organic as well as its inorganic environment, which all other theories—even the most recent—have failed to grapple with.
Wonderful Complexity of the Universe
The logical completeness as well as the extreme simplicity of this explanation of organic evolution has led great numbers of thoughtful but ill-informed persons to reject it, because it seems to render unnecessary the existence of a primary intelligent cause; while another equally large but, as I think, equally ill-informed class—the so-called monists—use it to demonstrate the non-existence, or, at all events, the needlessness, of any such cause. Both alike err, because they fail to take cognisance of the fact that every form of evolution, and pre-eminently that of the organic world, is an explanation of a process of change, a law of development, not in any sense or by any possibility an explanation of fundamental laws, causes, or origins. It presupposes the existence not only of matter—itself a thing whose nature is becoming more and more mysterious and unthinkable with the advance of physical science—but of all the vast complex of laws and forces which act upon it—mechanical, physical, chemical, and electrical laws and forces—all more or less dependent on the still more mysterious, all-pervading ether. Thus, the universe in its purely physical and inorganic aspect is now seen to be such an overwhelmingly complex organism as to suggest to most minds some vast intelligent power pervading and sustaining it.
Persons to whom this seems a logical necessity will not be much disturbed by the dilemma of the agnostics—that, however wonderful the material universe may be, a being who could bring it into existence must be more wonderful, and that they prefer to hold the lesser marvel to be self-existent rather than the greater. When, however, we pass from the inorganic to the organic world, governed by a new set of laws, and apparently by some regulating and controlling forces altogether distinct from those at work in inorganic nature; and when, further, we see that these organisms originated at some definite epoch when the earth had become adapted to sustain them, and thereafter developed into two great branches of non-sentient and sentient life, the latter gradually acquiring higher and higher senses and faculties till it culminated in man—a being whose higher intellectual and moral nature seems adapted for, even to call for, indefinite development—this logical necessity for some higher intelligence to which he himself owes his existence, and which alone rendered the origin of sentient life possible, will seem still more irresistible.
Mind Behind the World