proposed substance, the different elements of which will in this way have been in some sort separated. The impossi- bility of recombining the elements, to reproduce the primi- tive body, ought not to throw any doubt on the solution, ANALYSIS AND SYNTHESIS. 321 unless tlaere is some special reason for suspecting the simplicity of any one of the elements. Synthesis can, in this case, only add. a valuable confirmation to what was before not doubtful. But the case is very different when we have to determine only the immediate principles. As the elements concerned can produce combinations of diffe- rent orders, we can never be sure that one or more of the supposed immediate principles obtained does not result from the reactions caused by the analysis itself. It is only synthesis which, by reconstructing the proposed substance with the materials concerned, can decide the question con- clusively, though in some cases of feeble agency in the reactives, and strong analogical induction, there is no room left for reasonable doubt. In immediate analysis of great complexity, when the agreement of various analytical means strongly corroborates the conclusions obtained, we cannot rely on real chemical demonstration without the synthetical confirmation. This maxim of chemical philosophy is abun- dantly exemplified in the analysis of mineral waters, and yet more of organic substances.— It is noticeable that synthesis is easiest where it is most necessary, and would be most difiicult in the case of elementary analysis, where it can, as we have seen, be dispensed with. This is owing to the combinations becoming less tenacious as the order of composition of the constituent particles is higher; and if the decomposition is easy, so is the re-composition. The cases of immediate analysis require only feeble antagonisms, offering no great obstacles to the synthetical operations indispensable for their demonstration.
We have next to consider the encvclo- pedical position of Chemistry, to justify the gcJ'ence rank assigned to it in our scale.
It is from no vain and arbitrary consideration that Chemistry is placed between Physics and Physiology in our scale. By the iinportant series of electro-chemical 2)henomena Chemistry becomes, as it were, a prolongation of Physics: and at its other extreinity, it lays the founda- tions of physiology by its research intoorganic combinations. These relations are so real that it has sometimes haj^pened that chemists, untrained in the philosophy of science, have been uncertain whether a particular subject lay within 322 POSITIVE PHILOSOPHY.
their department, or ought to be referred, either to physics or to i^hysiology.
The phenomena of Chemistry are more complex than those of Physics, and are certainly dependent on them. Their degree of generality is inferior, — chemical effects requiring a much more extended concuri-ence of varied con- ditions. Physical properties belong not only to all sub- stances, but, with simple modifications, to all the states of aggregation, and even of combination, of each of them: whereas, it is only in a more or less determined and restricted condition that each body manifests its chemical j)roperties. In a word, nature often shows us physical effects apart from the chemical, while there can be no chemical effects apart from certain physical phenomena. Thus Chemistry cannot 1)6 rationally studied without a previous knowledge of physics. Besides, the most powerful chemical agents are derived from physics, which presents, in its different orders of phenomena, the first distinctive characters of different substances. It is impossible in our day to conceive of scientific chemistry without giving it the whole of p)hysics for its basis: and thus is its first rela- tion in the scale established. And, as physics is dependent on astronomy and mathematics, so must its own dependent be. But it must be owned that, with regard to doctrine, the connection of Chemistry with the first two sciences is neither extensive nor very important.
Every attempt to refer chemical questions to mathema- tical doctrines must be considered, now and always, pro- foundly irrational, as being contrary to the nature of the phenomena. In the case of physics, the mischief would be, as we have seen, merely from the misuse of Matibematkjs ^^ instrument which, properly directed, may be of admii'able efficacy: but if the employ- ment of mathematical analysis should ever become so pre- ponderant in chemistry (an aberration which is happily almost impossible) it wovild occasion vast and rapid retro- gradation, by substituting vague conceptions for positive ideas, and an easy algebraic verbiage for a laborious inves- tigation of facts. The direct subordination of chemistry , to astronomy is also slight, but more marked.
It is almost insensible in regard to abstract RELATIONS OF THE SCIENCE. 323 cliemistry, which alone is cultivated in onr day. But, when the time shall come for the development of concrete chemistry, — that is, the methodical application of chemical knowleda^e to the natural history of the a^lobe, — astrono- mical considerations will no doubt enter in where now there seems no point of contact between the two sciences. Geo- logy, immature as it is, hints to us such a future necessitv, some vague instinct of which was probably in the minds of philosophers in the theological age, when they were fancifully and yet obstinately bent on uniting astrologv and alchemy. It is, in fact, impossible to conceive of the great intestinal operations of the globe as radically inde- pendent of its planetary conditions. — Inconsiderable as are the relations of chemistry with mathematics and astronomv, in regard to doctrine, it is far otherwise with regard to method. It is easy to see how the perfection of chemistry might be secured and hastened bv the training of the minds of chemists in the mathematical spirit and astro- nomical philosophy. Besides that mathematical study is the necessary foundation of all positive science, it has a special use in chemistry in disciplining the mind to a wise severity in the conduct of analysis: and daily observation shows the evil effects of its absence. Yet, it can never be said that chemists have so much need of a mathematical education as phvsicists, because they do not need it as an instrument in daily use. but as an intellectual preparation for the rational study of nature. As to asti'onomy, we have seen that it constitutes the most perfect type of the study of nature; and this at once establishes its relation of superiority to chemistry. The more complex the pheno- mena, the more important is the influence of such a model; and it is only by having always before their eyes such an exemplification of the true spirit of natural philosophy, that chemists can rightly estimate the inanitv of the metaphy- sical explanations which vitiate their doctrine, and can acquire an adequate sense of the true character, conditions, and destiny of chemical science. Under this point of view, astronomy is more useful to chemists than even physics, in proportion to the superiority of its method.
So much for the sciences which precede rp p,., chemistry. As for those that follow, physi- ^' "' ' 324 POSITIVE PHILOSOPHY.
siology depends upon chemistry both as a point of departure and as a principal means of investigation. If we separate the phenomena of Hfe, properly so called, from those of auimahty, it is clear that the first, in the double intestinal movement which characterizes them, are essentially chemical. The processes which result from organization have peculiar characteristics; but apart from such modifi- cations, they are necessarily subjected to the general laws of chemical effects. Even in studying living bodies under a simply statical point of view, chemistry is of indisj^ens- able use in enabling us to distinguish with precision the different anatomical elements of any organism. — We shall see hereafter that the new science of Social Physics is m c ■ 1 (,■ - subordinated to chemical science. In the first place, it depends on it by its immediate and manifest connection with physiology: but, besides that, as social phenomena are the most complex and par- ticular of all, their laws must be subject to those of all the preceding orders, each of which manifests, in social science, its own peculiar influence. In regard to Chemistry especi- ally, it is evident that among the conditions of man's social existence several chemical harmonies between man and external circumstances are involved. Even if individual existence could be sustained, society could not, if these harmonies were destroyed, or even only somewhat dis- turbed,— as by changes in the atmospheric medium, or in the waters or the soil. _. The position of Chemistry amon^ the scisibFe perfection ^^^^^ being thus determined, the next inquiry is about the degree of scientific perfection that its nature admits, in comparison with others. As for the method, if jjhysics suffers from the intrusion of hypo- theses, we may say that chemistry has been their absolute prey, through its more difficult and tardy development. The doctrine of affinities appears to me more ontoiogical than that of fluids and imaginary ethers. If the electric fluid and the luminous ether are, as I called them before, materialized entities, affinities are at bottom jjure entities, as vague and indeterminate as those of the scholastic ])hilosophy of the Middle Age. The j^retended solutions that they yield are of the usual character of metaphysical HYPOTHESES. 325 stract terms, or tiie statement or the pneno- hypotheses.
menon. The advance of chemical knowledge whicli must at last discredit for ever sucli vain philosophy has as yet only modified it, so far as to disclose its radical futility. While affinities were regarded as absolute and invariable, there was at least something imposing in them; but since facts have compelled the belief of their being variable according to a multitude of circumstances, their use has only tended to prove, more and more, their utter inanity. Thus, for instance, it is known that at a certain temperature, iron decomposes water, or protoxide of hydro- gen: and yet, it has been since discovered that, under the influence of a higher temperature, hydrogen in its turn decomposes oxide of iron. What signifies, in this case, any order of affinity that we may ascribe to iron and hydrogen with oxygen? If we make the order vary with the tem- perature, we have a merely verbal, and therefore pretended explanation. Chemistry affords us now many such cases, apparently contradictory, independently of the long series of decisive considerations that have made us reject absolute affinities, — the only ones, after all, that have any scientific consistency whatever. The old habit is, however, so strong that even Berthollet, in the very work in whicli he overthrows the old doctrine of invariable or elective affinities, proposes vague affinities under many modifications. The strange doctrine of predisposing affinity is to be found in the work, among others, of the most rational of recent chemists, the illustrious Berzelius. When, for instance, water is decomposed by iron through the action of sulphuric acid, so as to disengage the hydrogen, this remarkable phenomenon is commonly attributed to the affinity of the sulphuric acid for the oxide of iron which tends to become formed. Now, can anything be imagined more metaphy- sical, or more radically incomprehensible, than the sympa- thetic action of one substance upon another which does not yet exist, and the formation of the last by virtue of this tnysterious affection? The strange fluids of physicists are rational and satisfactory in comparison with such notions. These considerations justify the desire that chemists should have a sufficient training in mathematical, 826 POSITIVE PHILOSOPHY.
astronomical, and then in physical philosophy, which have already put an end to such chimerical researches within their own domain, and would discard them speedily from the more complex parts of natural philosophy. It is only by having witnessed the purification m the anterior sciences that chemists could realize it in their own: and there could not be complete jjositivity in chemistry if metaphysics lingered in astronomy or physics. This, again, justities the place assigned to chemistry among the sciences. The indi- vidual must follow the general course of his race in his jjassage to the j^ositive state. He must hnd that true science consists, everywhere, in exact relations, established among observed facts, allowing the deduction of the most extensive series of secondary plienomena from the smallest jjossible number of original jjhenomena, jiuttiug aside all vain inquiry into causes and essences. And this is the spirit wliich has to be made preponderant in chemistry, — dissolving for ever the metaphysical doctrine of atn- nities...The inferiority of chemistry to physics, in fectioii regard to method and doctrine, explains its relative imperfection with regard to actual science. We have only to compare with the formula which told us what chemistry ought to be, what it actually is, to see that it is at an immense distance — much further than l^hysics — from its true scientific aim. Chemical facts are at this day essentially incoherent, or, at best, feebly co-ordinated by a small number of partial and insufficient relations, instead of those certain, extended, and uniform laws of which physics is so justly jjroud. As for prevision, if it is imperfect in jjhysics in comj^arison with astronomy, it can hardly be said to exist in chemistry at all: the issue of each chemical event being usually known only by speci- ally consulting the immediate experiment, when, as it were, the event is already accomplished.
Imperfect as chemistry is, in regard to imil'rf^^'ticJi'^ method and doctrine, it is yet superior to physiology, and still more, to social science, not only because, from the comparative simjjlicity of its })lienomena, the facts and investigations are clearer and more decisive, but because it has a few, though very few.
EDUCATIONAL FUXCTIOX. 327 real theories, capable of aifording complete previsions; a thing as yet impracticable, except in a general manner, with living bodies. We shall have occasion to notice the theory of proportions, the equivalent of which is not, in any sense, to be looked for in physiology. We must remember, while estimating the comparative imperfection of the sciences, that the importance to us of their perfection is in proportion to tlieir simplicity; our available means being always found to correspond with our reasonable wants. I hope, too, that this severe estimate of the actual state of each science will stimulate rather than discourage the student; for it is more gratifying to our human activity to conceive of the sciences as susceptible of vast, varied, aud indefinite progress, than to suppose them perfect, and therefore stationary, except in their secondary developments.
This leads us to consider the function of Chemistry in the education of the human mind.
It may be said to train us in the great art ^,,. c • J. i.- J. 1 • 1 Kelatioii to hiiot experimentation: not as being our exclu-,„^„ v>,.,..r.-a..
sive teacher, for, as we have seen, physics is superior to it in this: and it is more the art of observing than of experimenting that Chemistry is chiefly distin- guished for. But there is an important 2)art of the positive method which chemistry seems destined to carry to tlie highest perfection. I do not mean the theory of classifi- cations, of which chemists know too little at.,.
])resent; but tJie art of rational nomencla- ^lature tures, which is quite uncounected with classi- fications. Since the reform in chemical language, attempts have been incessantly made, to this hour, to form a syste- matic nomenclature in anatomy, in pathology, and especi- ally in zoology: but these endeavours have not had, and never can have, any success to compare with that of the reformers of chemical language; for the nature of the phenomena does not admit of it. It is not by accident that the chemical nomenclature is alone in its perfection. The moi'e complex phenomena are, and the more varied and less restricted the comparisons of objects, the more difficult it becomes to subject them to a system of deno- minations, at once rational and abridged, so as to facilitate the habitual combination of ideas. If the organs and 328 POSITIVE PHILOSOPHY.
tissues of the living body differed only from one point of view; if maladies were sufficiently defined by their seat; if, in zoology, genera, or at least families could be estab- lished by a homogeneous consideration, the corresponding sciences might at once admit of systematic nomenclatures as rational and as efficacious as that of Chemistry. But the diversity of aspects, rarely reducible to one head, renders such au arrangement extremely difficult and not very advantageous.
The case of chemistry is the only one in which, by its nature, the phenomena are simple, uniform and determinate enough to allow of a rational nomenclature at once clear, rapid and complete, so as to contribute to the general pro- gress of the science. The idea of composition, the great end of the science, is always preponderant. Thus, the systematic name of each body, expressing its composition, indicates first a correct general view, and then, the sum of its chemical history; and, by the nature of the science, the more it advances towards perfection, the more must this double property of the nomenclature be developed. In another view, dualism being the commonest constitution in chemistry, and the most essential, and that to which all other modes of composition are more and more refen-ed by science, we see that the conditions of the problem are as favourable as possible to a rapid and expressive nomen- clature. Thus, there has always been some system of nomenclature, more or less rough, though none to be com- pared to that so happily foiuided by Guyton-Morveau. Though the art can manifest its excellence only in propor- tion to the advance of chemisti*y, it is in such harmony with the nature of the science that, in its present imperfect state, it upholds it, by provisionally supplying, as it were, the almost absolute deficiency of ti-ue rationality. Thus chemistry may be regarded as specially adapted to develope one of the few fundamental means, the aggi'egate of which constitutes the general power of the human mind. The formation of a similar aid in the more complex sciences offers a real and strong interest: and I have only desired to show that we must resort to chemistry for the true principles and general spirit of the art of nomenclature, according to the rules so often set forth in this work.
STATE OF DOCTRINE. 329 that each, great logical artifice should he directly studied in the department of natural philosophy where it is found in the greatest perfection, that it may be after- wards applied in aid of the sciences to which it less specially belongs.
The high philosophical properties of Che- State of mistry are more striking in regard to doctrine chemical than to method. However imperfect our doctrine, chemical science is, its development has operated largely in the emancipation of the human mind. Its opposition to all theological philosophy is marked by the two general facts in which it has a share with all the rest of positive philosophy, — first, the prevision of phenomena, and next, our voluntary modification of them. We have already seen that the more the complexity of phenomena baffles our prevision, the greater becomes our power of modifying them, through the variety of resources afforded by the complexity itself; so that the anti-theological influence of science is infallible, in the one way or the other. In chemistry, our modifying power is so strong that the greater part of chemical phenomena owe their existence to human intervention, by which alone circumstances could be suitably arranged for their jjroduction: and if the phe- nomena of physiology and social science admit of modifi- cation in a yet greater degree, chemistry will always, in this particular, hold the first rank, since the highest order of modifications is that Avhich we here find, — those which are most important for the amelioration of the condition of Man, In the system of the action of man upon nature, chemistry must ever be regarded as the chief source of power, though all the fundamental sciences participate in it more or less.
In this way, chemistry effectually discredits the notion of the rule of a providential will among its phenomena. But there is another way in which it acts no less strongly; by abolishing the idea of desti'uction and creation in nature. Before anything was known of gaseous materials and pro- ducts, many striking appearances must inevitably have in- spired the idea of the real annihilation or production of matter in the general system of nature. These ideas could not yield to the true conception of decomposition and com- 330 POSITIVE PHILOSOPHY.
position till we had decomposed air and water, and then analysed vegetable and animal substances, and then finished with the analysis of alkalies and earths, thus exhibiting the fundamental principle of the indefinite perj^etuity of matter. In vital phenomena, the chemical examination of not only the substances of living bodies, but their functions, — im- perfect as it yet is, — must cast a strong light upon the economy of vital nature by showing that no organic matter radically heterogeneous to inorganic matter can exist, and that vital transformations are subject, like all others, to the universal laws of chemical phenomena. Chemical analysis seems to have fulfilled its function in this direc- tion: henceforth it must be by the more difficult, but more luminous method of synthesis that this great philo- sophical revolution must be completed: and attempts enough have been successfully made to pi'ove the possi- bility of it.
„...^ The divisions of the science have not been the science. clearly and permanently settled, partly be- cause of its very recent origin, and partly on account of its nature. In the first place, students have been more occuj^ied in multiplying observations than in classifying them; and in the next, the homogeneous character of chemical phenomena causes essential differ- ences to be less profound, and therefore less marked, than in any other of the fundamental sciences. In astronomy, there can be no question of a division into geometrical and mechanical phenomena. Physics is less a unique science than a group of almost isolated sciences; and they indicate their own arrangement. We shall see hereafter that nearly the same thing happens, though from a different cause, in physiology. But in chemistry, the conditions are less favourable, the distinctions being scarcely more marked than those which exist in a single department of physics, — as thermology, and yet more, electrology. The imj^erfec- tion and small importance of its present divisions are easily explained: and there are strong symptoms of an approaching discussion of this great subject; for the majority of eminent chemists are more or less dissatisfied with the provisional division which they have been hitherto obliged to accept as guidance in their labours.