And here let me fortify my position still farther, by the voice of a greater than Mädler – of one, moreover, to whom all the data of Mädler have long been familiar things, carefully and thoroughly considered. Referring to the elaborate calculations of Argelander – the very researches which form Mädler's basis – Humboldt, whose generalizing powers have never, perhaps been equalled, has the following observation:
»When we regard the real, proper, or non-perspective motions of the stars, we find many groups of them moving in opposite directions; and the data as yet in hand render it not necessary, at least, to conceive that the systems composing the Milky Way, or the clusters, generally, composing the Universe, are revolving about any particular centre unknown, whether luminous or non-luminous. It is but Man's longing for a fundamental First Cause, that impels both his intellect and fancy to the adoption of such an hypothesis.«9
The phænomenon here alluded to – that of ›many groups moving in opposite directions‹ – is quite inexplicable by Mädler's idea; but arises, as a necessary consequence, from that which forms the basis of this Discourse. While the merely general direction of each atom – of each moon, planet, star, or cluster – would, on my hypothesis, be, of course, absolutely rectilinear; while the general path of all bodies would be a right line leading to the centre of all; it is clear, nevertheless, that this general rectilinearity would be compounded of what, with scarcely any exaggeration, we may term an infinity of particular curves – an infinity of local deviations from rectilinearity – the result of continuous differences of relative position among the multudinous masses, as each proceeded on its own proper journey to the End.
I quoted, just now, from Sir John Herschel, the following words, used in reference to the clusters: – »On one hand, without a rotary motion and a centrifugal force, it is hardly possible not to regard them as in a state of progressive collapse.« The fact is, that, in surveying the ›nebulæ‹ with a telescope of high power, we shall find it quite impossible, having once conceived this idea of ›collapse,‹ not to gather, at all points, corroboration of the idea. A nucleus is always apparent, in the direction of which the stars seem to be precipitating themselves; nor can these nuclei be mistaken for merely perspective phænomena: – the clusters are really denser near the centre – sparser in the regions more remote from it. In a word, we see every thing as we should see it were a collapse taking place; but, in general, it may be said of these clusters, that we can fairly entertain, while looking at them, the idea of orbitual movement about a centre, only by admitting the possible existence, in the distant domains of space, of dynamical laws with which we are unacquainted.
On the part of Herschel, however, there is evidently a reluctance to regard the nebulæ as in ›a state of progressive collapse.‹ But if facts – if even appearances justify the supposition of their being in this state, why, it may well be demanded, is he disinclined to admit it? Simply on account of a prejudice; – merely because the supposition is at war with a preconceived and utterly baseless notion – that of the endlessness – that of the eternal stability of the Universe.
If the propositions of this Discourse are tenable, the ›state of progressive collapse‹ is precisely that state in which alone we are warranted in considering All Things; and, with due humility, let me here confess that, for my part, I am at a loss to conceive how any other understanding of the existing condition of affairs, could ever have made its way into the human brain. ›The tendency to collapse‹ and ›the attraction of gravitation‹ are convertible phrases. In using either, we speak of the rëaction of the First Act. Never was necessity less obvious than that of supposing Matter imbued with an ineradicable quality forming part of its material nature – a quality, or instinct, forever inseparable from it, and by dint of which inalienable principle every atom is perpetually impelled to seek its fellow-atom. Never was necessity less obvious than that of entertaining this unphilosophical idea. Going boldly behind the vulgar thought, we have to conceive, metaphysically, that the gravitating principle appertains to Matter temporarily – only while diffused – only while existing as Many instead of as One – appertains to it by virtue of its state of irradiation alone – appertains, in a word, altogether to its condition, and not in the slightest degree to itself. In this view, when the irradiation shall have returned into its source – when the rëaction shall be completed – the gravitating principle will no longer exist. And, in fact, astronomers, without at any time reaching the idea here suggested, seem to have been approximating it, in the assertion that ›if there were but one body in the Universe, it would be impossible to understand how the principle, Gravity, could obtain‹: – that is to say, from a consideration of Matter as they find it, they reach a conclusion at which I deductively arrive. That so pregnant a suggestion as the one quoted should have been permitted to remain so long unfruitful, is, nevertheless, a mystery which I find it difficult to fathom.
9 Betrachtet man die nicht perspectivischen eigenen Bewegungen der Sterne, so scheinen viele gruppenweise in ihrer Richtung entgegengesetzt; und die bisher gesammelten Thatsachen machen es auf's wenigste nicht nothwendig, anzunehmen, dass alle Theile unserer Sternenschicht oder gar der gesammten Sterneninseln, welche den Weltraum füllen, sich um einen grossen, unbekannten, leuchtenden oder dunkeln Centralkörper bewegen. Das Streben nach den letzten und höchsten Grundursachen macht freilich die reflectirende Thätigkeit des Menschen, wie seine Phantasie, zu einer solchen Annahme geneigt.