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he has not unconsciously assumed anything from his previous mental history: and that his ancient convictions of the external world had nothing to do with either the origination or development of the idea of God and his perfections. The speculators, however, who are not so plenarily convinced of this, must content themselves with congratulating him that he may now believe in their existence, but that they, so long as they have no other than his principles of reasoning to trust to, must doubt of his; that to them the external world still waits to be created.
Most, however, will content themselves, along with M. Cousin, by saying that the conviction of an external world does not stand in need of being proved by so circuitous a route, and by such very difficult feats of abstraction. They will even affirm that, as far as they are capable of judging, they fancy they see in mankind tolerably strong impressions of an external world a little before there are any traces of a conviction of the existence of God, whether more or less distinct; in fact, as soon as children are capable of feeling, and long before they are capable of saying, ‘Je pense, donc je suis.'
This we admit proves nothing: since, as Descartes may say, the irresistible conviction of an external world would not prove there was an external world: only then it must be said that when the proof at last comes, that there is an external world, it will merely prove what is already an irresistible conviction; and a proof, which proves only that, will be supposed by most philosophers a little too late and somewhat superfluous.
Having thus, during his temporary scepticism as to whether there be an external world, obtained the premises for proving it (slyly filching, however, from
that external world during the process those material symbols, words, - by which he carries on his processes of thought, and recording them at the same instant, with material pen, ink, and paper), Descartes henceforth considers that he may verily admit that there are other beings like himself, and that the impressions of his senses in relation to the material universe may be depended upon; a conclusion, again, which the world in general is disposed to arrive at without any logic at all, and which even philosophers are now very much disposed to adopt, not as a conclusion of any logic, but as a principle to be taken for granted; not to be proved by any philosophy, but one of the foundation stones of all philosophy: so that perhaps philosophers themselves will, in this respect at least, very soon be as wise as those who are none.
It will be seen from all this, that, however this great philosopher's ratiocination may, in fact, be doubted by the rest of mankind, the whole is a remarkable example of system: it proceeds from the fewest and most elementary principles, and is closely concatenated throughout. Thus it is with all his metaphysical philosophy at least; it was characteristic of the strictly analytic and deductive quality of his intellect. His metaphysics obviously form one fabric; consistent, granting his premises, however it may be doubted whether such premises can be granted. But too certain it is, that as our philosopher goes on, the demands on our faith become stronger and stronger, and the transition from link to link in the chain more and more precarious; till at last when we get to his physics - his exploded 'vortices' and his 'automatic brutes,' 'his animal spirits' and his mechanical physiology, we feel that we have but the bare word of a philosopher to trust to; and how little that
imports, we fear the history of hypothesis too abundantly declares. Little, in fact, remains undisputed, even of the metaphysical structure he built, except the celebrated corner-stone-'Je pense, donc je suis.' On that point, as on a pivot, the speculator may revolve for ever.
In entire consisteney with the à priori character of Descartes' metaphysical philosophy, were the predominant features of his system of physics: nay, as he flattered himself, the latter flowed in a series of unbroken deductions from the principles of the former. But, at all events, it was avowedly an attempt to deduce effects from causes; an investigation of what must be, not what is; the tracking of a stream from its fountain, not of a fountain from the stream. It is here that his philosophy comes into the sharpest collision with that of Bacon. Not that Descartes discarded experiment; he even thought that it would be more and more necessary to appeal to it at every stage in the progress of science. But into this point we will not further enter till we come briefly to characterise the comparative merits of the two systems, both of which involve important principles, equally necessary, though necessary in unequal proportions, to complete an unexceptionable apparatus of scientific discovery ;-to equip such a creature as man with a perfect 'method.' Descartes' system of physics, though often ingenious and subtle, and often profoundly suggestive, was just such a failure as might be expected when a merely mortal mind attempted to project, from a few à priori principles, assumed as facts of consciousness, the entire system of the universe; to evolve by logical concatenation what was the mode in which suns, planets, water, air, light, minerals, plants, animals—as to the last, however, he admits, we require
ample experiments,- must have been, or at all events may have been, successively constituted. He says,
'I have ever remained firm in my resolution of supposing no other principle than that I have employed in demonstrating the existence of God and the soul, and of receiving nothing for true which did not appear more clear and certain than the demonstrations of geometers had previously appeared; nevertheless, I venture to say that I have not only found the means of satisfying myself in a very little time, touching all the principal difficulties of which philosophy customarily treats; but also that I have remarked certain laws, which God has so established in nature and of which he has impressed such notions on our souls, that after having sufficiently reflected on them, we shall no longer doubt that they have been exactly observed in all which exists or has been created in the world.' -Method, p. 5.
The sublime audacity of the attempt almost makes us forget, for a moment, its presumption; but as we reflect on the immense accumulations of a score of sciences (half of them born since Descartes' day), and still how imperfectly,- separately or conjointly, they unlock the mysteries of nature; how little man yet knows, compared with what remains to be known by patient interpretation '-we are soon recalled to amazement rather at the temerity than the courage of the philosopher. How little, we are ready to exclaim, can even the mind of a Descartes 'anticipate' of the profundities of the universe; and how worthy is that cardinal maxim of Bacon of being deeply engraved on man's memory, as a lesson of humility as well as a truth in philosophy,- that the subtlety of nature far transcends the subtlety of either sense or intellect.' Viewed, in comparison with the actual accumulations. of modern science, the rude mechanical, and still ruder chemical hypotheses, by which Descartes ex
plains so many cosmical and physiological mysteries, appear even ludicrous. What must they be compared with the real exigencies of the case! It is thus he speaks of his first philosophical work which was to have been published with his 'Method;' but which the fate of Galileo made him suppress for a while. Never surely before were the several subjects of a philosophical treatise so curiously concatenated, nor so formidable an array of investigations undertaken, with such confidence by a single mind. 'Fearing,' says he, 'my inability to get into my discourse all that I had in my thoughts, I simply undertook to explain at large my notions of light; then of adding something about the sun and fixed stars, because it proceeds from them; then of the heavens, because they transmit it; then of the planets, comets, and the earth, because they reflect it; and in particular of all the bodies which are on the earth, because they are coloured, or transparent, or luminous; and lastly of man, because he is the spectator of it.'*
Yet Descartes had no misgivings: it is thus he speaks of his almost uniform success,-not indeed in always determining what were the modes in which the material universe, and its phenomena, must have been produced, but at least those by which a similar universe could have been produced.
The order I pursued was this: first, I endeavoured to discover in general the principles or first causes of every thing which is or can be in the world, without considering any thing for this purpose, except God alone who has created it, nor deducing these principles from aught else than from certain seeds of truth which exist naturally in our souls. After that,
* De la Méthode, Cinquième Partie. The creation of man,' says Leibnitz, gave Descartes little trouble; but then it must be confessed that his man was very different from the true.'