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DES CARTES.- -SYLVIUS DE LA BOE.-ROBERT BOYLE. Des Cartes' birth-His exile in Holland-His death in Sweden-His Physical Philosophy-His Vortices-Futility of his Physical Speculations-Sylvius de la Boe-Guy Patin-Use and Abuse of Antimony-Dialogue on Blood-letting between Willis and Van Helmont-Sylvius' Theory of Digestion-Guy Patin's Definition of Cardinal Mazarin-Bonteke's Praise of Tobacco-Robert Boyle -His Studies-Inclination towards Medicine-Just Estimate of ChemistryObjections to Compound Prescriptions-Expectation from Specifics-Objections to Specifics answered.-The Dose of a Specific.-Boyle the Expounder of the Baconian System of Medicine.

DES CARTES was born in 1596, Sylvius in 1614, twelve years before Bacon's death; and Boyle in 1627, the year Bacon died. René Des Cartes, or Latinised, Renatus Cartesius, was a gentleman of Brittany, a military man, possessing, in the highest degree," says his distinguished countryman, our defects and our qualities; clear, firm, resolute, somewhat rash; thinking in his closet with the same intrepidity with which he fought under the walls of Prague." 2

1 C. Van Dalen, junior, del. et sculpt.

He

2 Victor Cousin's History of Modern Philosophy.

passed the greater part of his life a voluntary exile in Holland, where he conceived he might enjoy greater liberty than he could in France. He died in Sweden, whither he had gone at the invitation of Queen Christina; and he is said to have been sacrificed to the rigour of the Swedish climate, as administered by his eccentric hostess, who insisted upon studying with him at five o'clock in the morning. "To Des Cartes," says Playfair, "belongs the honour of being the first who ventured on the solution of the most arduous problem which the material world offers to the consideration of philosophy. For this solution, he sought no other data than matter and motion, and with them alone proposed to explain the structure and constitution of the universe. The matter which he required, too, was of the simplest kind, possessing no properties but extension, impenetrability, and inertia. It was matter in the abstract, without any of its peculiar or distinguishing characters. To explain these characters was, indeed, a part of the task which he proposed to himself; and thus, by the simplicity of his assumptions, he added infinitely to the difficulty of the problem which he undertook to resolve." begins," says Whewell, "with his celebrated assertion, 'I think, therefore I am,' which appears to him a certain and immovable principle, by means of which he may proceed to something more. Accordingly, to this he soon adds the idea, and hence the certain existence of God and his perfections. He then asserts it to be also manifest, that a vacuum in any part of the universe is impossible; the whole must be filled with matter, and the matter must be divided into equal angular parts, this being the most simple, and therefore the most natural supposition.3 This matter being in motion the parts are necessarily ground into a spherical form, and the corners thus rubbed off (like filings or sawdust) form a

1 Biographical Dictionary.

Preliminary Dissertations to En

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"He

There is, besides, a third

second or more subtle matter.' kind of matter, of parts more coarse and less fitted for motion. The first matter makes luminous bodies, as the fixed stars; the second is the transparent substance of the skies; the third, the material of opaque bodies, as the earth, planets, and comets. We may suppose, also, that the motions of these parts take the form of revolving circular By this means, the first matter will

3

currents, or vortices.

2

be collected to the centre of each vortex, while the second, or subtle matter, surrounds it, and by its centrifugal effort constitutes light. The planets are carried round the sun by the motion of the vortex,* each planet being at such a distance from the sun as to be in a part of the vortex suitable to its solidity and mobility. The motions are prevented being exactly circular by various causes; for instance, a vortex may be pressed into an oval shape by contiguous vortices. The Satellites are in like manner carried round their primary planets, by subordinate vortices; while the comets have sometimes the liberty of gliding out of one vortex into the one contiguous, and thus travelling in a sinuous course from system to system through the universe." 5 Although Des Cartes himself styled his famous theory of vortices " A Philosophical Romance," yet it exerted a powerful influence upon the course of speculation both in physiology and pathology. Des Cartes was one of the earliest and most zealous supporters of Harvey, and while he accepted and defended the explanation given by our patient countryman of the cause of the circulation of the blood, he added to it his own imaginative hypothesis as to the production of animal heat. This he conceived to be owing to a fermentation of the blood in the heart; he compares it to the chemical action of an acid upon a metal, and the cause

1 Principia, p. 59.

2 Ibid., p. 56.

3 Ibid., p. 61.

Ibid., c. 140, p. 114.

6

5 Whewell's History of the Physical Sciences.

6 Sir William Hamilton's Dissertations on Philosophy, p. 304.

of the fermentation he ascribes to an ether (or the gas of Van Helmont), a spirit of some kind that vitalizes the fluid. As the blood proceeds in its course, it becomes more and more divided by this spiritual agency, and at the summit of its career in the brain, the spirit has at length effected its final divorce from the bodily element, and is at liberty-we may presume to enter into the court of the soul itself, which Des Cartes enthroned in the pineal gland, for the fanciful reason that this was the only part of the brain which was not double.

Such is the career of the emancipated spirit; but what becomes of the earthly companion in this dissolved alliance? This forsaken half, being matter, as we have seen, must be composed of atoms, or rather fragments, of various shapes and sizes, all hurried along in a perpetual whirl by the vortices. Of these fragments some are round, some triangular, some square. When a round atom arrives at the mouth of a round hole or pore, there is nothing to prevent its entrance; it is swept in by the force of the current, and finds itself at ease, and so moves on till it is taken up by the part requiring the nourishment it can afford. But, if instead of a round atom, a square one should be forced into a round hole, there occurs in the person of man all the evil consequences that result in the political frame when a round body is put into an office which Nature designed to be occupied by a square one, and we have obstruction of the Out of Des Cartes' physical romance this important doctrine took its rise-a doctrine which, under various modifications, long held sway in medicine, and powerfully affected the practice of the art.1

pores.

We may dismiss the consideration of Des Cartes' contribution to medicine, with the words applied by Playfair to his influence on physical science. "The philosophy of Des Cartes could explain all things equally well, and might

Sprengel, Vol. IV., p. 28.

have been accommodated as well to the system of Ptolemy or Tycho, as to that of Copernicus. It forms, therefore, no link in the chain of physical discovery; it served the cause of truth only by exploding errors more pernicious than itself, by exhausting a source of deception which might have misled other adventurers in science, and by leaving a striking proof how little advancement can be made in philosophy by pursuing any path but that of experiment and induction." 1 For philosophy, in the last sentence, we may substitute medicine, and add, that Des Cartes' visions of atoms and pores were of great indirect benefit, by setting men to determine, by actual microscopic inspection, whether they had a counterpart in reality. Thus, while exploding the errors of Galen, and his elements and humours, by a physical theory even of the most fantastic kind, he at the same time instigated the liberated intellect of his age, to cultivate a fertile field of improvement in anatomy and pathology.

Des Cartes' "starting principle-that all philosophy begins in an analysis of the human consciousness-is the foundation of all subsequent psychological investigations down to the present day."2 He is, therefore, considered the founder of modern mental philosophy; he was, besides, one of the greatest mathematicians that ever lived, being the first to apply algebra to the solution of geometrical problems; -SO we cannot wonder that, when this transcendent genius proclaimed the laws of physics, his utterances should be received with profound respect, and accepted as revelations of truth. But it is difficult to adapt our minds to the conditions of the period when Francis de la Boe Sylvius introduced into medicine his chemical theories, which received more attention, and exerted longer and deeper influence than the brilliant reveries of Des Cartes.

Dissert. Encyclop. Brit., p. 394.

2 An Historical and Critical View of the Speculative Philosophy of Europe

in the Nineteenth Century, by J. D.
Morrell, 2nd edit., p. 176. London.

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