"If it is to be regarded as demonstrated truth, or as receiving the smallest support from any observed numerical relations which actually hold good among the elements of the primary orbits, I beg leave to demur. Assuredly it receives no support from the observation of the effects of sidereal aggregation as exemplified in the formation of globular and elliptic clusters, supposing them to have resulted from such aggregation. For we see this cause working out in thousands of instances, to have resulted, not in the formation of a single large central body, surrounded by a few smaller attendants disposed in one plane around it, but in systems of infinitely greater complexity, consisting of multitudes of nearly equal luminaries, grouped together in a solid elliptic or globular form. So far then as any conclusions from our observations of nebulæ can go, the result of agglomerative tendencies may indeed be the formation of families of stars of a general and very striking character, but we see nothing to lead us to presume its further result to be the surrounding of those stars with planetary adherents."[206]
This theory is contradicted by the peculiarities of our solar system. The orbits of the comets being inclined at all angles to the sun's equator, are often out of the plane of his rotation, and so in the way of the theory. The moons of Uranus revolve in a direction contrary to all the other bodies, and fly right into the face of the theory. According to the nebular theory, the outer planets, first cast off from the sun, ought to be lighter than those nearer him, as these had longer pressing near the middle of the mass; and the sun himself, having been pressed by the weight of all the rest of the system, should be the densest body of the whole. And the author of The Vestiges of Creation, in expounding the theory, manufactures a set of facts to suit it, and tells his readers that the planets exhibit a progressive diminution in density from the one nearest the sun to that which is most distant. Our solar system could not have lasted thirty years had that been the case. The Earth, Venus, and Mars, are nearly of the same density. Uranus is more dense than Saturn, which is nearer the sun. Neptune is more dense than either. The sun, which ought to be the heaviest of all, according to the theory, is only one-fourth the density of the earth. La Place himself has demonstrated that these densities and arrangements are indispensable to the stability of the system. But they are plainly contradictory to his theory of its formation.[207]
The palpable difference of luminosity between the sun and the planets, which, as they are all made of the very same materials, and by the same process, according to this theory, ought to be equally self-luminous, is in itself a self-evident refutation of the nebular hypothesis, or of any other process of creation by mere mechanical law. "The same power, whether natural or supernatural, which placed the sun in the center of the six primary planets, placed Saturn in the center of the orb of his five secondary planets; and Jupiter in the center of his four secondary planets; and the earth in the center of the moon's orbit; and, therefore, had this cause been a blind one, without contrivance or design, the sun would have been a body of the same kind with Saturn, Jupiter, and the Earth; that is, without light or heat. Why there is one body in our system qualified to give light and heat to all the rest, I know no reason, but because the Author of the system thought it convenient." So says the immortal Newton.[208]
The great expounder of modern science—Humboldt—is equally explicit in enumerating the decisive marks of choice and will in the construction of the solar system, and in contemptuously dismissing the notion of development and creation by natural law from the halls of science.
"Up to the present time, we are ignorant, as I have already remarked, of any internal necessity—any mechanical law of nature—which (like the beautiful law which connects the square of the periods of revolution with the cube of the major axis) represents the above-named elements—the absolute magnitude of the planets, their density, flattening at the poles, velocity of rotation, and presence or absence of moons—of the order of succession of the individual planetary bodies of each group, in their dependence upon the distances. Although the planet which is nearest the sun is densest—even six or eight times denser than some of the exterior planets: Jupiter, Saturn, Uranus, and Neptune—the order of succession in the case of Venus, the Earth, and Mars, is very irregular. The absolute magnitudes do, generally, as Kepler has already observed, increase with the distances; but this does not hold good when the planets are considered individually. Mars is smaller than the Earth; Uranus smaller than Saturn; Saturn smaller than Jupiter, and succeeds immediately to a host of planets, which, on account of their smallness, are almost immeasurable. It is true, the period of rotation generally increases with the distance from the sun; but it is in the case of Mars slower than in that of the Earth, and slower in Saturn than in Jupiter."[209] "Our knowledge of the primeval ages of the world's physical history does not extend sufficiently far to allow of our depicting the present condition of things as one of development."[210]
Sir David Brewster adds his testimony as follows: "Geology does not pretend to give us any information respecting the process by which the nucleus of the earth was formed. Some speculative astronomers indeed have presumptuously embarked in such an inquiry; but there is not a trace of evidence that the solid nucleus of the globe was formed by secondary causes, such as the aggregation of attenuated matter diffused through space; and the nebular theory, as it has been called, though maintained by a few distinguished names, has, we think, been overturned by arguments which have never been answered. Sir Isaac Newton, in his four celebrated letters to Dr. Bentley, has demonstrated that the planets of the solar system could not have been thus formed and put in motion round a central sun."[211]
4. Astronomy not only exposes the folly of past cosmogonies, but demonstrates the impossibility of framing any true theory of creation, and thus refutes all future cosmogonies.
The grand error of all cosmogonies lies in the arrogant assumption, on which every one of them must be founded, that the theorist is acquainted with all substances, and all forces in the universe, and with all the modes of their operation; not only at the present period, and on this earth, but in all past ages, and in worlds in widely different, and utterly unknown situations; for, if he be ignorant of any substance, or of any active force in the universe, his generalization is avowedly imperfect, and necessarily erroneous. That unknown force must have had its influence in framing the world. Its omission, then, is fatal to the theory which neglects it. A theory of creation, for instance, which would neglect the attraction of gravitation would be manifestly false. But there are other forces as far reaching, whose omission must be equally fatal; for instance, the power of repulsion.
A conviction of this truth has given rise to a constant effort to simplify matters down to the level of our ignorance, by reducing all substances to one, or at most two simple elements, and all forces to the form of one universal law; but the progress of science utterly blasts the attempt. Instead of simplifying matters, the very chemical processes undertaken with that view revealed new substances, and every year increases our knowledge of nature's variety. No scientific man now dreams of one primeval element. In the same way, astronomy, which, it was boasted, would enable us to account for all the operations of the universe, by reducing all motion to one mechanical law, has revealed to us the existence of other forces as far reaching as the attraction of gravitation, and more powerful; and substances whose nature and combinations are utterly unknown. But every cosmogony is just an attempt to simplify matters, by ignoring the existence of these unknown substances, and mysterious forces; a process which science condemns, as utterly unphilosophical and absurd.