Outline of the Natural Sciences Pt. II

The circulation of the blood was long since known; but the disposition of the vessels which conveyed the chyle to mix with it, and repair its losses; the existence of a gastric fluid which disposes the elements to the decomposition necessary to separate from organised matter, that portion which is proper to become assimilated with the living fluids; the changes undergone by the various parts and organs in the interval between conception and birth, and afterwards during the different ages of life; the distinction between the parts possessing sensibility and those in which irritability only resides, a property discovered by Haller, and common to almost every organic substance: these facts are the whole of what physiology has been enabled to discover, by indubitable observations, during this brilliant epoch; and these important truths may serve as an apology for the numerous explanations, mechanical, chemical, and organical, which have succeeded each other, and loaded this science with hypotheses destructive to its progress, and dangerous when used as the ground of medical practice. To the outline of the sciences we may add that of the arts, which, being founded upon them, have advanced with greater certainty, and broken the shackles of custom and common practice, which heretofore impeded their progress.

We may shew the influence which the progress of mechanics, of astronomy, of optics, and of the art of measuring time, has exercised on the art of constructing, moving, and directing vessels at sea. We may shew how greatly an increase of the number of observers, and a greater degree of accuracy in the astronomical determinations of positions, and in topographical methods, have at last produced an acquaintance with the surface of the globe, of which so little was known at the end of the last century.

How greatly the mechanic arts, properly so called, have given perfection to the processes of art in constructing instruments and machines in the practice of trade, and these last have no less added force to rational mechanism and philosophy. These arts are also greatly indebted to the employment of first movers already known, with less of expence and loss, as well as to the invention of new principles of motion.

We have beheld architecture extend its researches into the science of equilibriums and the theory of fluids, for the means of giving the most commodious and least expensive form to arches, without fear of altering their solidity; and to oppose against the effort of water a resistance computed with greater certainty; to direct the course of that fluid, and to employ it in canals with greater skill and success.

We have beheld the arts dependent on chymistry enriched with new processes; the ancient methods have been simplified, and cleared from useless or noxious substances, and from absurd or imperfect practices introduced from former rude trials; means have been invented to avert those frequently terrible dangers to which workmen were exposed. Thus it is that the application of science has secured to us more of riches and enjoyment, with much less of painful sacrifice or of regret.

In the mean time, chemistry, botany, and natural history, have very much enlightened the economical arts, and the culture of vegetables destined to supply our wants; such as the art of supporting, multiplying, and preserving domestic animals; the bringing their races to perfection, and meliorating their products; the art of preparing and preserving the productions of the earth, or those articles which are of animal product.

Surgery and pharmacy have become almost new arts, from the period when anatomy and chemistry have offered them more enlightened and more certain direction.

The art of medicine, for in its practice it must be considered as an art, is by this means delivered at least of its false theories, its pedantic jargon, its destructive course of practice, and the servile submission to the authority of men, or the doctrine of colleges; it is taught to depend only on experience. The means of this art have become multiplied, and their combination and application better known; and though it may be admitted that in some parts its progress is merely of a negative kind, that is to say, in the destruction of dangerous practices and hurtful prejudices, yet the new methods of studying chemical medicine, and of combining observations, give us reason to expect more real and certain advances.

We may endeavour more especially to trace that practice of genius in the sciences which at one time descends from an abstract and profound theory to learned and delicate applications; at another, simplifying its means, and proportioning them to its wants, concludes by spreading its advantages through the most ordinary practices; and at others again being rouzed by the wants of this same course of art, it plunges into the most remote speculations, in search of resources which the ordinary state of our knowledge must have refused.

We may remark that those declamations which are made against the utility of theories, even in the most simple arts, have never shewn any thing but the ignorance of the declaimers. We may prove that it is not to the profundity of these theories, but, on the contrary, to their imperfection, that we ought to attribute the inutility or unhappy effects of so many useless applications.

These observations will lead us to one general truth, that in all the arts the results of theory are necessarily modified in practice; that certain sources of inaccuracy exist, which are really inevitable, of which our aim should be to render the effect insensible, without indulging the chimerical hope of removing them; that a great number of data relative to our wants, our means, our time, and our expences which are necessarily overlooked in the theory, must enter into the relative problem of immediate and real practice; and that, lastly by introducing these requisites with that skill which truly constitutes the genius of the practical man, we may at the same time go beyond the narrow limits wherein prejudice against theory threatens to detain the arts, and prevent those errors into which an improper use of theory might lead us.

Those sciences which are remote from each other, cannot be extended without bringing them nearer, and forming points of contact between them.

From Condorcet's Ninth Epoch. A survey of the world of science and a call for the need for the different sciences to find points where they touch in order to strengthen.