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I examined what would be the first and most ordinary effects which might be deduced from these causes; and it seems to me that I could hence discover heavens, stars, and earth, and even upon that earth, water, air, fire, minerals, and some other things which are the most common, most simple, and in consequence most easy to be known.'- Method, p. 5.
Richly amusing and surely as deeply instructive is the naïveté with which our metaphysical Columbus speaks of his voyage to Chaos: - 'Totus nunc sum in Chao digerendo ut ex eo lumen educam.'* The time for reducing it to order, and evolving the sun, moon, and stars from it, he afterwards modestly fixes at not less than two or three months; though he had at first hoped that 'one or two' might be sufficient. After all, he seems to deem this construction of the universe hardly more difficult than that of expounding it in such a way as, while 'conveying the truth,' should not strike any body's imagination with excess of wonder,' — truly a feat which we should think impossible nor be repugnant to received opinions,' a feat at least equally so. Hard fate of the philosopher! to be obliged to reduce chaos to order, and yet never shock the chaos of received opinions.† Yet he meditates still more difficult things. He says (Epist. 67.):
"Two or three months ago, I pitched myself into the depths of space—me in cœlum penitissime conjeci—and after I had satisfied myself as to the nature of the heavens, and the more conspicuous stars, and as to many other things which a few years ago I should have despaired of, I am now grown so audacious that I am going to investigate the cause of the position of every fixed star.'
* Epist. 65. Pars II.
† 'Res mille simul considerandæ veniunt, ut modum inveniam quo verum dicendo, nullius imaginationem percellam, et opiniones jam receptos non impugnem.'
In another letter, written about the same time, he condescends to remark that the subject of comets especially does demand a considerable amount of observations, and suggests that if a number of amateurs would furnish them, for the behoof of the deductive philosopher, as the data of his reasonings, it might be of admirable consequence.* In the same letter he exhibits a trait of despondency very unusual with him. He almost despairs (though he says he cannot refrain from allowing his mind to pursue the theme) of ascertaining the reasons for the position of every fixed star.' Reflecting on the (even now somewhat imperfect!) condition of sidereal astronomy, the reader will not wonder that Descartes had not quite exhausted this immeasurable subject; but we must regret it the more as he somewhat darkly observes,— though, as other letters show, no believer in astrology, -that the knowledge of this order of the stars is the key and foundation of the profoundest and most perfect science which men can attain respecting the material universe; because in virtue of it all the forms and essences of terrene bodies may be known à priori; whereas without that knowledge we must
* Sir John Herschel enforces a somewhat similar suggestion of Lalande, in his admirable treatise on Astronomy. (Ch. xii. on 'Sidereal Astronomy.') It is well that the suggestion should be made, and if acted upon with conscientious diligence, might lead to important results. But we fear that little value can be attached to mere amateur efforts in any department of science. If observations and experiments are made with the requisite tact, care, and accuracy, then the observers must be, on that subject, philosophers, and cease to be amateurs; if not, by misleading into error they will be apt, as we say of slovenly servants, to make more work than they save; at all events, their work requires to be done over again, and the practical philosopher is just where he
be contented to conjecture them à posteriori and in their effects;'-a dictum of à priori philosophy, which the reader must take for granted: though we certainly think that when man has discovered the reasons for the position of every fixed star (though not because he has done so), he will very probably be also in possession of those other mysteries, of which it is to be the key.
Amidst the natural insufficiencies and errors of Descartes' account of the modes in which the universe may be supposed to have been evolved, the idea of that evolution itself as a methodical progression development from the operation of vast mechanical, chemical, and other laws, in virtue of which the heavens and the earth naturally assumed their present form, is a conception the probability of which modern science is confirming; nor must the merit of entertaining it be grudgingly denied to Descartes, scanty and jejune as is the apparatus of causes by which he accounts for the all but infinite effects. It is an idea, however, which he timidly disclaims as the true theory of the subject; and affirms that he only thinks every thing might have been produced in such a course of development. We shall nevertheless concede him the honour he is anxious to divest himself of; for it is pretty certain that he is here merely fencing. His dread of the odium and persecution attendant upon alleged heterodoxy is constantly impelling him to say that he reasons ex hypothesi, when we can yet see that he believes the hypothesis to be fact. However, his words are, 'I do not wish it to be inferred from my reasonings, that the world has been created in the mode I have explained; for it is much more probable that God made it from the beginning such as it was to be.'
So confident is the tone in which Descartes speaks of his à priori system, of the possible construction of a universe on his principles; so firm is his tread over what he deems a 'pavement of adamant,' that we can hardly divest ourselves of the belief that he would have been willing to stand a test to which few even of the most sanguine of the children of philosophy would venture to submit. We have sometimes thought that if the Supreme were pleased to delegate for awhile his omnipotence to some archangel, instructed to furnish the human fabricators of his universe with the elements of their hypotheses (atoms and forces and combinations of these according to their own definition), on condition of their attempting to realise their conceptions,-most of them would, at last, shrink from the proffer, lest the ignominy of utter failure should awaken shouts of laughter at the short-sightedness of their paper theories. We almost think that Descartes would boldly persevere, and still affirm, as he has done, that though he did not assert that the universe was really constructed in his way (but probably in 'methods much more perfect'), yet that on his plan a very decent universe might be constructed notwithstanding; and it would probably require a few gyrations in one of his own 'vortices' thoroughly to undeceive him.
The presumption of this truly vast and profound intellect, its total misestimate of the exigencies of the great problems with which it had to deal, as tested by the comparative triviality of all the accumulations of science since his time, towards a complete solution of those problems, ought to be profoundly instructive; it proclaims the unsearchable wisdom of God,' and teaches us that modesty and humility are the chiefest ornaments of man.
D'Alembert has admirably urged every thing that can be said in palliation of the extravagances of Descartes' physics. Still, after all allowance for the age in which he wrote, we can hardly excuse the perfect gratuitousness of his hypotheses, and still less the confidence and presumption with which he trusted to them, after Bacon had traced those immortal lines, -Modulos vero ineptos mundorum, et tanquam simiolas, quas in philosophiis phantasiæ hominum extruxerunt, omnino dissipandas edicimus. Sciant itaque homines quantum intersit, inter humanæ mentis idola et divinæ mentis ideas.' Leibnitz, contrasting the professed deductive rigour and concatenated force of Descartes' reasonings (his principles once admitted), with the perfect gratuitousness of the pure assumptions interpolated at various points in the chain, remarks, 'Methodi ejus tantum propositum amo; nam quum in rem præsentem ventum est, ab illâ severitate prorsus remisit, et ad hypotheses quasdam miras ex abrupto delapsus est.' Of the facility with which Descartes can intrude an arbitrary ex tempore assumption, one of the most amusing examples is given in his explanation of the reasons of our seeing only one side of the moon. (Principia, pars III. art. 152.)
The favourite argument of the early Cartesians, that granting the first principles of their master, his entire philosophy, physical as well as metaphysical, follows by rigid deduction, is well ridiculed in the somewhat tedious philosophical romance, 'A Voyage to the World of Cartesius.' The truth is, that in his physical theories Descartes introduced a new principle just whenever he thought proper. Yet M. Bouillier, in his really eloquent Eloge, thinks that Descartes, having seen that the true theory of the universe was a problem of dynamics, 'a préparé