The Two Great Discoveries.

The present age has witnessed the establishment of two great principles in scientific investigation,—the principle that, whenever force disappears in one form, its reappearance must be looked for in some other form,—and the principle that, no matter what changes, or events, or developments take place in the universe, their causes must be sought within Nature, and not outside of or above it.

The first of these principles is implied in the great discovery of the "conservation and correlation of forces," or, as Herbert Spencer more aptly names it, the "persistence of force." Through the labors of Rumford, Grove, Joule, Mayer, Helmholtz, Tyndall, Carpenter, and the other powerful minds whose combined genius has brought to light this grandest of all known laws of Nature, the great truth that the universe is a unit, long held by philosophy as a speculation, has been inductively established by science as a fact. Various as may be its manifestations, there is but one Power in Nature, uncreatable and indestructible, omnipresent, infinite, and eternal. Incapable of augmentation or diminution, appearing and disappearing and reappearing, it is the One in the Many, the Permanent in the Transient. Thus the old dream of a "creation" either vanishes altogether or merges[unclear: And] page 12 sis of the uncreated; and the birth of Nature, celebrated in all cosmogonies as a momentary supernatural event, becomes in modern thought an eternal natural process. If thus the miraculous "beginning of all things," so much relied on as a pet proof of the Deity, slips from the fingers of theology forever, none the less is the history of all things rescued from the contempt heaped upon it by those who see nothing divine in the common. Rash and eager theologians, like James Martineau [Essays, Philosophical and Theological, "Nature and God," 1866] and the writer in the Quarterly Review already quoted, have leaped to the conclusion that this one Energy pervading the universe is reducible to Will. But science disallows such hasty reduction. The analogies of the human will, like arrows shot at the sun, fall back without reaching the mark. Nature refuses to lend herself to such anthropomorphic interpretations, and insists that the débris of the old supernaturalism shall not be emptied into her domain as into a vacant city-lot. Nevertheless, in this magnificent truth that the universe is a unit,—that Nature is the eternal self-expression of infinite and omnipresent Power,—I cannot but discern the first grand element of that idea of God of which science shall yet be the architect.

The other great principle I referred to is implied by the law of Evolution—more particularly the law of genealogical descent which Mr. Darwin has shown to include, not only individuals, but also species. The nebular hypothesis of Laplace and the uniformitarian theory of Hutton were incomplete till supplemented by the Darwinian theory in biology. Sociology, history, ethics, philosophy, religion, all illustrate the same great law of evolution, as treated by all the best and latest writers; but the origin of species was the stronghold of supernaturalism until Darwin and Wallace had scientifically formulated the law of Natural Selection. The luminous vindication of the unity and universality of natural law which science owes to their labors in a region previously haunted by the nocturnal depredators privileged to prey on the common sense of mankind, has been the heaviest blow struck of late years at the effete theology of the past. The philosophical and religious value of the Darwinian theory lies in this fact, that it throws the light of reason into a corner of science itself whither the bats and owls had betaken themselves, fancying it sacred to darkness forever. A brave flapping of wings and ruffling of plumage and blinding of eyes page 13 has there been, since the daylight streamed unexpectedly into that nook! Henceforth science shall shine there also, and the surprised marauders shall stand as stuffed specimens in some museum of extinct superstitions. And no one shall mourn save those who believe that light is irreligious, and taxidermy a sacrilege.

The law of evolution brings into harmony the facts which had been disrupted by the belief of miraculous interventions in the course of Nature. The creation of the universe, the cataclysmal epochs of the earth's history, the birth of new species, had been the strongholds of supernaturalism. Now they are all razed to the ground. Not only is unity of Power a fixed fact hereafter, but also unity of Law. In the favorite phrase of Alexander von Humboldt, universal Nature is "ein lebendiges Ganze"—"a living Whole." That conception is the glory of science. It marks the triumph of intellect over its environment. It gives to human life a sublime ideal, and converts the Stoic's grand aspiration of "living according to Nature" into the highest law of civilized man. To bring human society and the human soul into unity with the great Whole of which these are parts becomes thus the chief end of the religion based on science; and when Bryant concludes his "Forest Hymn" with these elevated lines—

"——Be it ours to meditate.
In these calm shades, thy milder majesty.
And to the beautiful order of thy works
Learn to conform the order of our lives,"—

he expresses with great dignity and beauty the innermost spirit of the faith which, under the influence of science, is silently shaping itself in the heart of the modern world.