Читать книгу Modern Atheism under its forms of Pantheism, Materialism, Secularism, Development, and Natural Laws - James Buchanan - Страница 13

The doctrine of a Nebular Cosmogony was first suggested by some observations of the elder Herschell on those cloud-like appearances which may be discerned in various parts of the heavens by the aid of the telescope, or even, in some cases, by the naked eye. It assumed a more definite form in the hands of La Place, although even by him it was offered, not as an ascertained discovery of science, but simply as a hypothetical explanation of the way in which the production of the planets and their satellites might possibly be accounted for by the operation of the known laws of Nature.

The explanation of the whole theory may be best understood by dividing it into two parts: the first being that which attempts to account for the formation of planets and satellites, on the assumption of the existence of a central sun, and of certain other specified conditions; the second being that which undertakes to account for the formation of the sun itself, on the assumption of the existence of a diffused nebulous matter in space, or, as it has been aptly called, "a universal Fire-Mist."[28]

When the theory is limited to the explanation of the origin of the planets and their satellites, the original condition of our solar system is assumed to have been widely different from what it now is; the sun is supposed to have existed for a time alone, to have revolved upon his axis, and to have been surrounded with an atmosphere expanded by intense heat, and extending far beyond the limits of our system as it now exists. This solar atmosphere revolved, like the sun itself, around its axis; but its heat, constantly radiated into sidereal space, gradually diminished, and the atmosphere being contracted in proportion as it cooled, the rapidity of its rotation was accelerated, until it reached the point at which the central attraction was overcome by the centrifugal force, and then a zone of vapor would be detached or thrown off, which might either retain its form as a nebulous ring, like the ring of Saturn, or first breaking into fragments, from some want of continuity in its structure, and afterwards coalescing into one mass, might be condensed into a planet as the vapor continued to cool. These rings or planets, thus detached from the central atmospheric mass, would continue to revolve, in virtue of the force originally impressed upon them, and their motion would be nearly circular, in the same plane and in the same direction with that of the sun. The first planet, so formed, must have been that at the extreme limit of our solar system; the second the next in point of remoteness from the centre, and so on; each resulting from the operation of the same natural laws, and emerging into distinct existence at that precise point in the gradual cooling and contraction of the atmosphere at which the centrifugal became stronger than the centripetal force. But each planet might also be subjected to the same process of cooling and contracting, and might therefore throw off, under the operation of the same mechanical laws, zones of vapor more or less dense, which might consolidate into moons or satellites, and which should also revolve, like the planets, round their primary. Thus, Uranus has six satellites, and Saturn seven; while the latter has also thrown off two zones so perfectly uniform in their internal structure that they remain unbroken, and constitute a double ring around the planet.

In this first form of the theory, which assumes the existence of the sun and its atmosphere, and the rotation of both round an axis, La Place sought to give a scientific form to the speculations of Sir William Herschell on the condensation of Nebulæ, by proving simply the dynamical possibility of the formation of a planetary system by such means, according to the known laws of matter and motion; but he did not affirm the scientific certainty of his conjecture, and far less the actual production of the solar system in this way. He has been followed by M. Comte, who has attempted to furnish, if not a complete demonstration, at least a plausible mathematical verification, of the hypothesis.[29] Utterly excluding all supernatural agency in the work of creation, he equally excludes from the problem which he attempts to solve, the origin of the sun and its atmosphere; and confining himself to the task of accounting, in the way not of demonstrative certainty, but merely of plausible hypothesis, for the formation of the planets and satellites of our solar system, he conceives the theory of La Place to be susceptible of such a numerical verification as is sufficient to give it a high degree of verisimilitude. Assuming that the periodic time of each planet must be equal to that of the portion of the solar atmosphere of which it was formed at the era when it was thrown off, and combining the theorems of Huygens on the measure of centrifugal forces with Newton's law of gravitation, he establishes a simple equation between the time of the rotation of each zone or section of the solar atmosphere, and the distance of the corresponding planets. On applying this equation to the various bodies of our system, he found that the periodic time of the moon agrees, at least within the tenth of a day, with the duration of the earth's revolution, when her atmosphere is supposed to have extended to the moon; and that the periodic times of the planets maintain a similar correspondence with what must have been the duration of the solar revolution when they were severally thrown off from its atmosphere. It is the less necessary, however, to enter on a detailed exposition of his argument, because he admits that it can afford at the utmost only a probable proof of an hypothesis; and further, because it is expressly limited to the production of the planets and their satellites, while not only is the existence of the solar atmosphere presupposed, but also its existence in a certain state, and with several determinate conditions; while no account whatever is given of the origin either of the sun or its atmosphere, and none of the laws or conditions on which the whole process of development is confessedly dependent.

But the author of "The Vestiges" takes a much wider range, and attempts a more arduous task. He seeks to account for the origin both of suns and of solar systems by the agency of natural laws. Not content with the more limited form of the theory, which M. Comte holds to be the only legitimate or practical object of scientific treatment, he holds that the origin of the sun itself, and the forms, the positions, the relations, and the motions, of all the heavenly bodies, may be accounted for by supposing a previous state of matter, fluid or gasiform, subject only to the law of gravitation. The Nebular Cosmogony, which is well characterized by himself as his "version of the romance of Nature," is based on the assumption that "the nebulous matter of space, previously to the formation of stellar and planetary bodies, must have been a universal Fire-Mist,"[30] in other words, a diffused luminous vapor, intensely hot, which might be gradually condensed into a fluid, and then into a solid state, by losing less or more of its heat. The existence of such a luminous matter being assumed, and it being further supposed that it was not entirely uniform or homogeneous, but that it existed in various states of condensation, and that it had "certain nuclei established in it which might become centres of aggregation for the neighboring diffused matter,"—the author attempts to show that on such centres a rotatory motion would be established wherever, as was the most likely case, there was any obliquity in the lines of direction in which the opposing currents met each other; that this motion would increase as the agglomeration proceeded; that at certain intervals the centrifugal force, acting on the remoter part of the rotating mass, would overcome the agglomerating force; and that a series of rings would thus be left apart, each possessing the motion proper to itself at the crisis of separation. These, again, would only continue in their annular form, if they were entirely uniform in their internal structure. There being many chances against this, they would probably break up in the first instance, and be thereafter "agglomerated into one or several masses, which would become representatives of the primary mass, and perhaps give rise to a progeny of inferior masses." In support of this theory, reference is made to the existence, at the present moment, of certain cloud-like nebulæ, or masses of diffused luminous matter, exhibiting a variety of appearances, as if they were in various degrees of condensation, and which are described as "solar systems in the process of being formed" out of a previous condition of matter. And the observations of M. Plateau, of Ghent, are adduced as affording an experimental verification of some parts of the theory, and, especially, as serving to explain the spherical form of the planets, the flattening at the poles, and the swelling out at the equator.

It does not belong to our proper province, nor is it necessary for our present purpose, to discuss the merits of this theory, considered as a question of science. This has been already done, with various degrees of ability, but with unwonted unanimity, by some of the ablest men of the age—by Whewell, Sedgwick and Mason, in England, by Sir David Brewster and Mr. Miller, in Scotland, and by Professor Dod and President Hitchcock, in America.[31] But, viewing it simply in its relation to the Theistic argument, we conceive that the adverse presumption which it may possibly generate in some minds against the evidence of Natural Theology, will be effectually neutralized by establishing the following positions:

That it is a mere hypothesis, and one which, from the very nature of the case, is incapable of being proved by such evidence as is necessary to establish a matter of fact.

That the progress of scientific discovery, so far from tending to verify and confirm, has served rather to disprove and invalidate the fundamental assumption on which it rests.

That even were it admitted, either as a possible, or probable, or certain explanation of the origin of the present planetary systems, it would not necessarily destroy the evidence of Theology, nor establish on its ruins the cause of Atheism.

Each of these positions may be conclusively established, and the three combined constitute a complete answer to the theory of Development, in so far as it has been applied in the support or defence of Atheism.

1. That it is a mere hypothesis or conjecture, designed, not to establish the historical fact, but to explain merely the dynamical possibility of the production of the planetary bodies by the operation of known natural laws, must be admitted, I think, even by its most enthusiastic admirers. It might have seemed, indeed, to have something like a basis of fact to rest upon, had the conception of the elder Herschell been verified, when he announced the existence of a nebulous fluid, capable of being distinguished, by certain well-defined marks, from unresolved clusters of stars; but even then it presupposed so many postulates, which could in no way be established by experimental or historical evidence, that it could scarcely be regarded in any other light than as an ingenious speculation or a splendid conjecture. For, let it be considered, first of all, that the theory proceeds on the assumption of the existence and wide diffusion of a nebulous fluid of whose reality there is no actual proof; secondly, that it necessarily requires, also, the supposed existence of certain favorable conditions; and, thirdly, the operation of certain invariable laws; and it will be manifest at once that it is purely hypothetical throughout, and that it includes a variety of topics which never have been, and never can be made the subjects of experimental verification. For it postulates, in the words of an acute writer, "the establishment of nuclei in the body of the elemental mass, as well as the action of heat on its substance, and then seeks to explain the concentration of the nebulous particles into these nuclei by the force of gravitation, the rotation of the bodies so produced by the confluence of the nebulous fluid, the separation of a portion of the outer surface of these revolving masses in the form of rings, the disruption of these rings, and the subsequent recomposition of their fragments into separate spheres, answering to the planets and satellites of our system."[32] But even were the existence of a nebulous fluid admitted, we have no access to know what was its internal structure; we cannot determine whether it was uniform and homogeneous throughout, or whether it contained nuclei which might become centres of aggregation; we have no means of estimating the intensity of the heat which belonged to it, or of calculating the process by which it was dispersed, so as to occasion the condensation of successive portions of the mass. No eye ever saw the separation of any part of it in the form of a ring, or the disruption of that ring, or the subsequent recomposition of its fragments into a solid sphere. And even had all this been matter, not of mere conjecture, but of actual observation, it would still have left much to be explained which can only be accounted for by ascribing it to a designing Intelligent Cause.

2. The progress of scientific discovery, so far from tending to verify, has served rather to invalidate the fundamental assumption on which the whole theory depends. That assumption was the existence of a Nebulous Fluid or Fire-Mist, capable of being distinguished, by certain characteristic marks, from unresolved nebulæ or clusters of stars. The existence of any such fluid has become more and more doubtful, in proportion as astronomers have been enabled, with the aid of larger and better constructed telescopes, to resolve several nebulæ which had previously defied the power of less perfect instruments. We do not affirm that every cluster has been already resolved, nor is it necessary for the purposes of our argument to suppose that, at any future time, this stupendous achievement is likely to be effected; for it is a very obvious consideration, that just in proportion as our telescopic powers are enlarged so as to enable us to resolve many of the nearer nebulæ, they must also bring within the range of our extended vision others more remote and hitherto unperceived, which may continue to exhibit the same cloud-like appearance as the former, until, by a new improvement of the telescope, we may succeed in separating them into distinct stars; and even then the march of discovery is not ended—we may reasonably expect that with every fresh increase of telescopic vision, new clusters will be brought into view, and new clouds appear in the utmost verge of the horizon. But, unquestionably, the progress which has already been made in this direction affords a strong presumption in favor of the idea, that the apparent nebulosity of those masses which still appear, even to our best telescopes, as cloud-like vapors, is to be ascribed rather to the imperfection of our instruments than to any difference between them and such as have been already resolved. Sir John Herschell, a high authority in such a case, tells us that "we have every reason to believe, at least in the generality of cases, that a nebula is nothing more than a cluster of stars."[33] Sir David Brewster is equally explicit: "It was certainly a rash generalization to maintain that nebulæ differed essentially from clusters of stars, because existing telescopes could not resolve them. The very first application of Lord Rosse's telescopes to the heavens overturned the hypothesis; and with such unequivocal facts as that instrument has brought to light, we regard it as a most unwarrantable assumption to suppose that there are in the heavenly spaces any masses of matter different from solid bodies, composing planetary systems."[34] And Professor Nichol, while he gracefully acknowledges that he has "somewhat altered the views which he formerly gave to the public, as the highest then known and generally entertained, regarding the structure of the heavens," states, as the result of more mature reflection, that "the supposed distribution of a self-luminous fluid, in separate patches, through the heavens, has, beyond all doubt, been proved fallacious by that most remarkable of telescopic achievements—the resolution of the great nebula in Orion into a superb cluster of stars; and that this discovery necessitates important changes in previous speculations on Cosmogony."[35]

In short, Lord Rosse's observations at Parsonstown have conclusively proved that what appeared to be a nebula was in reality a cluster of stars; and while they still leave many nebulæ unresolved, they afford a strong warrant for believing that discoveries in the same direction might be indefinitely extended in proportion to the increase of telescopic power.

3. But even were the Nebular Hypothesis admitted, and were the Theory of Development by Natural Laws conceived to afford a satisfactory explanation of the origin of the planetary systems, it would not follow, as a necessary consequence, that the peculiar evidence of Theism—that on which it mainly depends, and to which it makes its most confident appeal—would be thereby destroyed, or even diminished. The only legitimate result of such a doctrine would seem to be, that we must distinguish aright between a work of Mediate, and a work of Immediate Creation. In the Bible each of these is distinctly recognized. We have a specimen of the one in the creation of the first man by the direct agency of Divine power; we have a specimen of the other in the creation, less direct but equally real, of all his natural posterity, through the medium of ordinary generation. Men do not cease to be the creatures of God because they are born of their parents, in virtue of that creative word, "Be fruitful, and multiply, and replenish the earth;" and hence children are admonished "to remember their Creator in the days of their youth."[36] The work of creation is equally real and equally Divine, whether it be effected mediately or immediately, with or without the intervention of means, by the direct and instantaneous exertion of Almighty power, or by the gradual and successive operation of second causes acting according to established laws. In the ordinary course of Providence, the method of mediate production, gradual growth, and progressive development, may be observed in innumerable instances; but it can never be justly held to exclude, or even to obscure, the evidence of a presiding Intelligence and a supernatural Power. On the contrary, it may serve rather to enhance that evidence; since the very arrangements and provisions which have been made with a view to the reproduction of every thing after its kind, may bear on them the legible impress of a designing Mind and an ordaining Will. Thus, year by year continually, the whole inhabitants of the world are supported by the fruits of harvest, which are produced and matured under the action of natural laws; yet every intelligent Theist ascribes the result ultimately to the goodness, wisdom, and power of God, and sees in the very processes by which it is brought to pass some of the most signal proofs of these Divine perfections.

Now, as this method is followed in the work of Providence, which may be, and often has been, described as a continuous creation, and yet has no tendency to destroy, or even to diminish, the evidence of a presiding Intelligence in Nature, so no good reason can be assigned why it might not also have been adopted in the production of planets and astral systems, if so it had seemed good to Supreme Wisdom. If this method was adopted for the propagation of plants and animals, no reason can be given why it might not also have been adopted for the production of planets and moons; nor would it in the latter case, any more than in the former, impair the evidence of God's creative wisdom and power. For, suppose it be possible that, by a marvellous process of self-evolution, the material elements of Nature might assume new forms, so as to originate a succession of new worlds and new planetary systems, without the immediate or direct interposition of a Supernatural Will; suppose that the earth and the other bodies now belonging to our own system, were generated out of a prior condition of matter, existing in a gasiform state and diffused through space as a Fire-Mist, subject to the ordinary action of heat and gravitation; suppose, in short, that there were LAWS FOR THE GENERATION OF WORLDS in the larger cycles of time, just as there ARE LAWS FOR THE GENERATION OF ANIMALS in the short ages of terrestrial life;—would a provision for such a succession of marvellous developments necessarily destroy, or even impair, the evidence for the being and perfections of God? Does the generation of the animated tribes diminish the evidence of design in the actual constitution of the world? And why should a similar provision, if any such were found to exist, for the generation of stars and systems, be regarded in any other light than as an exhibition, on a still larger scale, of "the manifold wisdom of God?"

Let it ever be remembered that the Theistic argument depends, not on the mode of production, but on the character of the resulting product. The world may have been produced mediately or immediately, with or without the operation of natural laws; but if it exhibit such an arrangement of parts, such an adaptation of means to ends, or such a combination of collocations and adjustments, as enables us at once to discern the distinctive marks of intelligent design, the evidence cannot be diminished, it may even be possibly enhanced, by the method of production. Provision is made, doubtless, for the growth and development of the eye, the ear, and the hand, in the human fœtus, and the process by which they are gradually formed is regulated by natural laws. But the resulting products are so exquisitely constructed, so admirably adapted to the elements of nature, and so evidently designed for the uses of life, that they irresistibly suggest the idea of wise and benevolent contrivances; and this idea is as strong and clear as it could have been had they been produced instantaneously by the direct act of creative power. And so of the planets and astral systems: they may have been generated, that is, produced, in a way of natural development; yet the resulting products are such as to evince the supreme wisdom and beneficence which presided over their formation. But even this is not all. Let us suppose, further, that Philosophy may yet reach its extreme, and, as we humbly conceive, unattainable limit; let us suppose that it may succeed in decomposing all the chemical elements now known, by resolving them into ONE primary basis; let us even suppose that it may succeed in reducing all the subordinate laws of Nature into ONE supreme and universal law; still the development of such a system as we see around us out of such materials, and by such means, would not be necessarily exclusive of the idea of God, but might afford evidence of a Supreme Mind, creating, combining, and controlling all things for the manifestation of His adorable perfections.

We have thus seen that the Theory of Cosmical Development is a mere hypothesis, incapable of experimental or historical proof; that the recent progress of scientific discovery has tended to disprove the fundamental assumption on which it rests; and that, even were it admitted as a possible, or, still more, as a plausible explanation of the origin of planets and astral systems, it would not serve to destroy, and scarcely, if at all, to diminish the evidence of Theism.

The last of these positions, if well established, might seem to supersede the necessity of discussing the hypothesis at all in connection with our present theme. But such a discussion of it as has been offered may be useful to those—and they are not a few—who, superficially acquainted with Science in its more popular form, are exposed to the danger of being seduced by the authority of a few distinguished names which have unfortunately become identified with the cause of Atheism. For, while the author of "The Vestiges" repudiates the atheistic conclusions which some have deduced from his hypothesis, M. Comte boldly avows his creed in the following revolting terms: "To minds unacquainted with the study of the heavenly bodies, Astronomy has still the reputation of being a science eminently religious, as if the famous verse, 'Cœli enarrant gloriam Dei' ('The heavens declare the glory of God'), had preserved all its force." And, he adds, in a note, "At present, to minds that have been early familiarized with the true astronomical philosophy, the heavens declare no other glory than that of Hipparchus, Kepler, Newton, and all those who have contributed to the establishment of their laws!" The reader of these laws may become illustrious, but the Maker of them must be utterly ignored!