PART V.

RELATION TO OTHER PURSUITS--RELATION TO PHILOSOPHY. 716. The investigator of nature cannot be required to be a philosopher, but it is expected that he should so far have attained the habit of philosophizing, as to distinguish himself essentially from the world, in order to associate himself with it again in a higher sense. He should form to himself a method in accordance with observation, but he should take heed not to reduce observation to mere notion, to substitute words for this notion, and to use and deal with these words as if they were things. He should be acquainted with the labours of philosophers, in order to follow up the phenomena which have been the subject of his observation, into the philosophic region. 717. It cannot be required that the philosopher should be a naturalist, and yet his co-operation in physical researches is as necessary as it is desirable. He needs not an acquaintance with details for this, but only a clear view of those conclusions where insulated facts meet. 718. We have before (175) alluded to this important consideration, and repeat it here where it is in its place. The worst that can happen to physical science as well as to many other kinds of knowledge is, that men should treat a secondary phenomenon as a primordial one, and (since it is impossible to derive the original fact from the secondary state), seek to explain what is in reality the cause by an effect made to usurp its place. Hence arises an endless confusion, a mere verbiage, a constant endeavour to seek and to find subterfuges whenever truth presents itself and threatens to be overpowering. 719. While the observer, the investigator of nature, is thus dissatisfied in finding that the appearances he sees still contradict a received theory, the philosopher can calmly continue to operate in his abstract department on a false result, for no result is so false but that it can be made to appear valid, as form without substance, by some means or other. 720. If, on the other hand, the investigator of nature can attain to the knowledge of that which we have called a primordial phenomenon, he is safe; and the philosopher with him. The investigator of nature is safe, since he is persuaded that he has here arrived at the limits of his science, that he finds himself at the height of experimental research; a height whence he can look back upon the details of observation in all its steps, and forwards into, if he cannot enter, the regions of theory. The philosopher is safe, for he receives from the experimentalist an ultimate fact, which, in his hands, now becomes an elementary one. He now justly pays little attention to appearances which are understood to be secondary, whether he already finds them scientifically arranged, or whether they present themselves to his casual observation scattered and confused. Should he even be inclined to go over this experimental ground himself, and not be averse to examination in detail, he does this conveniently, instead of lingering too long in the consideration of secondary and intermediate circumstances, or hastily passing them over without becoming accurately acquainted with them. 721. To place the doctrine of colours nearer, in this sense, within the philosopher's reach, was the author's wish; and although the execution of his purpose, from various causes, does not correspond with his intention, he will still keep this object in view in an intended recapitulation, as well as in the polemical and historical portions of his work; for he will have to return to the consideration of this point hereafter, on an occasion where it will be necessary to speak with less reserve. RELATION TO MATHEMATICS. 722. It may be expected that the investigator of nature, who proposes to treat the science of natural philosophy in its entire range, should be a mathematician. In the middle ages, mathematics was the chief organ by means of which men hoped to master the secrets of nature, and even now, geometry in certain departments of physics, is justly considered of first importance. 723. The author can boast of no attainments of this kind, and on this account confines himself to departments of science which are independent of geometry; departments which in modern times have been opened up far and wide. 724. It will be universally allowed that mathematics, one of the noblest auxiliaries which can be employed by man, has, in one point of view, been of the greatest use to the physical sciences; but that, by a false application of its methods, it has, in many respects, been prejudicial to them, is also not to be denied; we find it here and there reluctantly admitted. 725. The theory of colours, in particular, has suffered much, and its progress has been incalculably retarded by having been mixed up with optics generally, a science which cannot dispense with mathematics; whereas the theory of colours, in strictness, may be investigated quite independently of optics. 726. But besides this there was an additional evil. A great mathematician was possessed with an entirely false notion on the physical origin of colours; yet, owing to his great authority as a geometer, the mistakes which he committed as an experimentalist long became sanctioned in the eyes of a world ever fettered in prejudices. 727. The author of the present inquiry has endeavoured throughout to keep the theory of colours distinct from the mathematics, although there are evidently certain points where the assistance of geometry would be desirable. Had not the unprejudiced mathematicians, with whom he has had, or still has, the good fortune to be acquainted, been prevented by other occupations from making common cause with him, his work would not have wanted some merit in this respect. But this very want may be in the end advantageous, since it may now become the object of the enlightened mathematician to ascertain where the doctrine of colours is in need of his aid, and how he can contribute the means at his command with a view to the complete elucidation of this branch of physics. 728. In general it were to be wished that the Germans, who render such good service to science, while they adopt all that is good from other nations, could by degrees accustom themselves to work in concert. We live, it must be confessed, in an age, the habits of which are directly opposed to such a wish. Every one seeks, not only to be original in his views, but to be independent of the labours of others, or at least to persuade himself that he is so, even in the course of his life and occupation. It is very often remarked that men who undoubtedly have accomplished much, quote themselves only, their own writings, journals, and compendiums; whereas it would be far more advantageous for the individual, and for the world, if many were devoted to a common pursuit. The conduct of our neighbours the French is, in this respect, worthy of imitation; we have a pleasing instance in Cuvier's preface to his "Tableau Élémentaire de l'Histoire Naturelle des Animaux." 729. He who has observed science and its progress with an unprejudiced eye, might even ask whether it is desirable that so many occupations and aims, though allied to each other, should be united in one person, and whether it would not be more suitable for the limited powers of the human mind to distinguish, for example, the investigator and inventor, from him who employs and applies the result of experiment? Astronomers, who devote themselves to the observation of the heavens and the discovery or enumeration of stars, have in modern times formed, to a certain extent, a distinct class from those who calculate the orbits, consider the universe in its connexion, and more accurately define its laws. The history of the doctrine of colours will often lead us back to these considerations. RELATION TO THE TECHNICAL OPERATIONS OF THE DYER. 730. If in our labours we have gone out of the province of the mathematician, we have, on the other hand, endeavoured to meet the practical views of the dyer; and although the chapter which treats of colour in a chemical point of view is not the most complete and circumstantial, yet in that portion, as well as in our general observations respecting colour, the dyer will find his views assisted far more than by the theory hitherto in vogue, which failed to afford him any assistance. 731. It is curious, in this view, to take a glance at the works containing directions on the art of dyeing. As the Catholic, on entering his temple, sprinkles himself with holy water, and after bending the knee, proceeds perhaps to converse with his friends on his affairs, without any especial devotion; so all the treatises on dyeing begin with a respectful allusion to the accredited theory, without afterwards exhibiting a single trace of any principle deduced from this theory, or showing that it has thrown light on any part of the art, or that it offers any useful hints in furtherance of practical methods. 732. On the other hand, there are men who, after having become thoroughly and experimentally acquainted with the nature of dyes, have not been able to reconcile their observations with the received theory; who have, in short, discovered its weak points, and sought for a general view more consonant to nature and experience. When we come to the names of Castel and Gülich, in our historical review, we shall have occasion to enter into this more fully, and an opportunity will then present itself to show that an assiduous experience in taking advantage of every accident may, in fact, be said almost to exhaust the knowledge of the province to which it is confined. The high and complete result is then submitted to the theorist, who, if he examines facts with accuracy, and reasons with candour, will find such materials eminently useful as a basis for his conclusions.--Note A A. RELATION TO PHYSIOLOGY AND PATHOLOGY. 733. If the phenomena adduced in the chapter where colours were considered in a physiological and pathological view are for the most part generally known, still some new views, mixed up with them, will not be unacceptable to the physiologist. We especially hope to have given him cause to be satisfied by classing certain phenomena which stood alone, under analogous facts, and thus, in some measure, to have prepared the way for his further investigations. 734. The appendix on pathological colours, again, is admitted to be scanty and unconnected. We reflect, however, that Germany can boast of men who are not only highly experienced in this department, but are likewise so distinguished for general cultivation, that it can cost them but little to revise this portion, to complete what has been sketched, and at the same time to connect it with the higher facts of organisation. RELATION TO NATURAL HISTORY. 735. If we may at all hope that natural history will gradually be modified by the principle of deducing the ordinary appearances of nature from higher phenomena, the author believes he may have given some hints and introductory views bearing on this object also. As colour, in its infinite variety, exhibits itself on the surface of living beings, it becomes an important part of the outward indications, by means of which we can discover what passes underneath. 736. In one point of view it is certainly not to be too much relied on, on account of its indefinite and mutable nature; yet even this mutability, inasmuch as it exhibits itself as a constant quality, again becomes a criterion of a mutable vitality; and the author wishes nothing more than that time may be granted him to develop the results of his observations on this subject more fully; here they would not be in their place. RELATION TO GENERAL PHYSICS. 737. The state in which general physics now is, appears, again, particularly favourable to our labours; for natural philosophy, owing to indefatigable and variously directed research, has gradually attained such eminence, that it appears not impossible to refer a boundless empiricism to one centre. 738. Without referring to subjects which are too far removed from our own province, we observe that the formulæ under which the elementary appearances of nature are expressed, altogether tend in this direction; and it is easy to see that through this correspondence of expression, a correspondence in meaning will necessarily be soon arrived at. 739. True observers of nature, however they may differ in opinion in other respects, will agree that all which presents itself as appearance, all that we meet with as phenomenon, must either indicate an original division which is capable of union, or an original unity which admits of division, and that the phenomenon will present itself accordingly. To divide the united, to unite the divided, is the life of nature; this is the eternal systole and diastole, the eternal collapsion and expansion, the inspiration and expiration of the world in which we live and move. 740. It is hardly necessary to observe that what we here express as number and restrict to dualism is to be understood in a higher sense; the appearance of a third, a fourth order of facts progressively developing themselves is to be similarly understood; but actual observation should, above all, be the basis of all these expressions. 741. Iron is known to us as a peculiar substance, different from other substances: in its ordinary state we look upon it as a mere material remarkable only on account of its fitness for various uses and applications. How little, however, is necessary to do away with the comparative insignificancy of this substance. A two-fold power is called forth,[1] which, while it tends again to a state of union, and, as it were, seeks itself, acquires a kind of magical relation with its like, and propagates this double property, which is in fact but a principle of reunion, throughout all bodies of the same kind. We here first observe the mere substance, iron; we see the division that takes place in it propagate itself and disappear, and again easily become re-excited. This, according to our mode of thinking, is a primordial phenomenon in immediate relation with its idea, and which acknowledges nothing earthly beyond it. 742. Electricity is again peculiarly characterised. As a mere quality we are unacquainted with it; for us it is a nothing, a zero, a mere point, which, however, dwells in all apparent existences, and at the same time is the point of origin whence, on the slightest stimulus, a double appearance presents itself, an appearance which only manifests itself to vanish. The conditions under which this manifestation is excited are infinitely varied, according to the nature of particular bodies. From the rudest mechanical friction of very different substances with one another, to the mere contiguity of two entirely similar bodies, the phenomenon is present and stirring, nay, striking and powerful, and so decided and specific, that when we employ the terms or formulæ polarity, plus and minus, for north and south, for glass and resin, we do so justifiably and in conformity with nature. 743. This phenomenon, although it especially affects the surface, is yet by no means superficial. It influences the tendency or determination of material qualities, and connects itself in immediate co-operation with the important double phenomenon which takes place so universally in chemistry,--oxydation, and de-oxydation. 744. To introduce and include the appearances of colour in this series, this circle of phenomena was the object of our labours. What we have not succeeded in others will accomplish. We found a primordial vast contrast between light and darkness, which may be more generally expressed by light and its absence. We looked for the intermediate state, and sought by means of it to compose the visible world of light, shade, and colour. In the prosecution of this we employed various terms applicable to the development of the phenomena, terms which we adopted from the theories of magnetism, of electricity, and of chemistry. It was necessary, however, to extend this terminology, since we found ourselves in an abstract region, and had to express more complicated relations. 745. If electricity and galvanism, in their general character, are distinguished as superior to the more limited exhibition of magnetic phenomena, it may be said that colour, although coming under similar laws, is still superior; for since it addresses itself to the noble sense of vision, its perfections are more generally displayed. Compare the varied effects which result from the augmentation of yellow and blue to red, from the combination of these two higher extremes to pure red, and the union of the two inferior extremes to green. What a far more varied scheme is apparent here than that in which magnetism and electricity are comprehended. These last phenomena may be said to be inferior again on another account; for though they penetrate and give life to the universe, they cannot address themselves to man in a higher sense in order to his employing them æsthetically. The general, simple, physical law must first be elevated and diversified itself in order to be available for elevated uses. 746. If the reader, in this spirit, recalls what has been stated by us throughout, generally and in detail, with regard to colour, he will himself pursue and unfold what has been here only lightly hinted at. He will augur well for science, technical processes, and art, if it should prove possible to rescue the attractive subject of the doctrine of colours from the atomic restriction and isolation in which it has been banished, in order to restore it to the general dynamic flow of life and action which the present age loves to recognise in nature. These considerations will press upon us more strongly when, in the historical portion, we shall have to speak of many an enterprising and intelligent man who failed to possess his contemporaries with his convictions. RELATION TO THE THEORY OF MUSIC. 747. Before we proceed to the moral associations of colour, and the æsthetic influences arising from them, we have here to say a few words on its relation to melody. That a certain relation exists between the two, has been always felt; this is proved by the frequent comparisons we meet with, sometimes as passing allusions, sometimes as circumstantial parallels. The error which writers have fallen into in trying to establish this analogy we would thus define: 748. Colour and sound do not admit of being directly compared together in any way, but both are referable to a higher formula, both are derivable, although each for itself, from this higher law. They are like two rivers which have their source in one and the same mountain, but subsequently pursue their way under totally different conditions in two totally different regions, so that throughout the whole course of both no two points can be compared. Both are general, elementary effects acting according to the general law of separation and tendency to union, of undulation and oscillation, yet acting thus in wholly different provinces, in different modes, on different elementary mediums, for different senses.--Note B B. 749. Could some investigator rightly adopt the method in which we have connected the doctrine of colours with natural philosophy generally, and happily supply what has escaped or been missed by us, the theory of sound, we are persuaded, might be perfectly connected with general physics: at present it stands, as it were, isolated within the circle of science. 750. It is true it would be an undertaking of the greatest difficulty to do away with the positive character which we are now accustomed to attribute to music--a character resulting from the achievements of practical skill, from accidental, mathematical, æsthetical influences--and to substitute for all this a merely physical inquiry tending to resolve the science into its first elements. Yet considering the point at which science and art are now arrived, considering the many excellent preparatory investigations that have been made relative to this subject, we may perhaps still see it accomplished. CONCLUDING OBSERVATIONS ON TERMINOLOGY. 751. We never sufficiently reflect that a language, strictly speaking, can only be symbolical and figurative, that it can never express things directly, but only, as it were, reflectedly. This is especially the case in speaking of qualities which are only imperfectly presented to observation, which might rather be called powers than objects, and which are ever in movement throughout nature. They are not to be arrested, and yet we find it necessary to describe them; hence we look for all kinds of formulæ in order, figuratively at least, to define them. 752. Metaphysical formulæ have breadth as well as depth, but on this very account they require a corresponding import; the danger here is vagueness. Mathematical expressions may in many cases be very conveniently and happily employed, but there is always an inflexibility in them, and we presently feel their inadequacy; for even in elementary cases we are very soon conscious of an incommensurable idea; they are, besides, only intelligible to those who are especially conversant in the sciences to which such formulæ are appropriated. The terms of the science of mechanics are more addressed to the ordinary mind, but they are ordinary in other senses, and always have something unpolished; they destroy the inward life to offer from without an insufficient substitute for it. The formulæ of the corpuscular theories are nearly allied to the last; through them the mutable becomes rigid, description and expression uncouth: while, again, moral terms, which undoubtedly can express nicer relations, have the effect of mere symbols in the end, and are in danger of being lost in a play of wit. 753. If, however, a writer could use all these modes of description and expression with perfect command, and thus give forth the result of his observations on the phenomena of nature in a diversified language; if he could preserve himself from predilections, still embodying a lively meaning in as animated an expression, we might look for much instruction communicated in the most agreeable of forms. 754. Yet, how difficult it is to avoid substituting the sign for the thing; how difficult to keep the essential quality still living before us, and not to kill it with the word. With all this, we are exposed in modern times to a still greater danger by adopting expressions and terminologies from all branches of knowledge and science to embody our views of simple nature. Astronomy, cosmology, geology, natural history, nay religion and mysticism, are called in in aid; and how often do we not find a general idea and an elementary state rather hidden and obscured than elucidated and brought nearer to us by the employment of terms, the application of which is strictly specific and secondary. We are quite aware of the necessity which led to the introduction and general adoption of such a language, we also know that it has become in a certain sense indispensable; but it is only a moderate, unpretending recourse to it, with an internal conviction of its fitness, that can recommend it. 755. After all, the most desirable principle would be that writers should borrow the expressions employed to describe the details of a given province of investigation from the province itself; treating the simplest phenomenon as an elementary formula, and deriving and developing the more complicated designations from this. 756. The necessity and suitableness of such a conventional language where the elementary sign expresses the appearance itself, has been duly appreciated by extending, for instance, the application of the term polarity, which is borrowed from the magnet to electricity, &c. The _plus_ and _minus_ which may be substituted for this, have found as suitable an application to many phenomena; even the musician, probably without troubling himself about these other departments, has been naturally led to express the leading difference in the modes of melody by _major_ and _minor_. 757. For ourselves we have long wished to introduce the term polarity into the doctrine of colours; with what right and in what sense, the present work may show. Perhaps we may hereafter find room to connect the elementary phenomena together according to our mode, by a similar use of symbolical terms, terms which must at all times convey the directly corresponding idea; we shall thus render more explicit what has been here only alluded to generally, and perhaps too vaguely expressed. [1] Eine Entzweyung geht vor; literally, _a division takes place_. According to some, the two magnetic powers are previously in the bar, and are then separated at the ends.--T.