All around us are the traces of this glorious and successful struggle. Indeed, it seems as if in Europe there was nothing man feared to attempt. The invasions of the sea repelled, and whole provinces, as in the case of Holland, rescued from its grasp, mountains cut through and turned into level roads; soils of the most obstinate sterility becoming exuberant, from the mere advance of chemical knowledge; while, in regard to electric phenomena, we see the subtlest, the most rapid, and the most mysterious of all forces, made the medium of thought, and obeying even the most capricious behests of the human mind.
In other instances, where the products of the external world have been refractory, man has succeeded in destroying what he could hardly hope to subjugate. The most cruel diseases, such as the plague, properly so called, and the leprosy of the Middle Ages,[282] have entirely disappeared from the civilized parts of Europe; and it is scarcely possible that they should ever again be seen there. Wild beasts and birds of prey have been extirpated, and are no longer allowed to infest the haunts of civilised men. Those frightful famines, by which Europe used to be ravaged several times in every century,[283] have ceased; and so successfully have we grappled with them, that there is not the slightest fear of their ever returning with any thing like their former severity. Indeed, our resources are now so great, that we could at worst, only suffer from a slight and temporary scarcity: since, in the present state of knowledge, the evil would be met at the outset by remedies which chemical science could easily suggest.[284]
It is hardly necessary to notice how, in numerous other instances, the progress of European civilization has been marked by the diminished influence of the external world: I mean, of course, those peculiarities of the external world which have an existence independent of the wishes of man, and were not created by him. The most advanced nations do, in their present state, owe comparatively little to those original features of nature which, in every civilization out of Europe, exercised unlimited power. Thus, in Asia and elsewhere, the course of trade, the extent of commerce, and many similar circumstances, were determined by the existence of rivers, by the facility with which they could be navigated, and by the number and goodness of the adjoining harbours. But, in Europe, the determining cause is, not so much these physical peculiarities, as the skill and energy of man. Formerly the richest countries were those in which nature was most bountiful; now the richest countries are those in which man is most active. For, in our age of the world, if nature is parsimonious, we know how to compensate her deficiencies. If a river is difficult to navigate, or a country difficult to traverse, our engineers can correct the error, and remedy the evil. If we have no rivers, we make canals; if we have no natural harbours, we make artificial ones. And so marked is this tendency to impair the authority of natural phenomena, that it is seen even in the distribution of the people, since, in the most civilized parts of Europe, the population of the towns is everywhere outstripping that of the country; and it is evident that the more men congregate in great cities, the more they will become accustomed to draw their materials of thought from the business of human life, and the less attention they will pay to those peculiarities of nature, which are the fertile source of superstition, and by which, in every civilization out of Europe, the progress of man was arrested.
From these facts it may be fairly inferred, that the advance of European civilization is characterized by a diminishing influence of physical laws, and an increasing influence of mental laws. The complete proof of this generalization can be collected only from history; and therefore I must reserve a large share of the evidence on which it is founded for the future volumes of this work. But that the proposition is fundamentally true must be admitted by whoever, in addition to the arguments just adduced, will concede two premiss is, neither of which seem susceptible of much dispute. The first premiss is, that we are in possession of no evidence that the powers of nature have ever been permanently increased; and that we have no reason to expect that any such increase can take place. The other premiss is, that we have abundant evidence that the resources of the human mind have become more powerful, more numerous, and more able to grapple with the difficulties of the external world; because every fresh accession to our knowledge supplies fresh means with which we can either control the operations of nature, or, failing in that, can foresee the consequences, and thus avoid what it is impossible to prevent; in both instances, diminishing the pressure exercised on us by external agents.
If these premisses are admitted, we are led to a conclusion which is of great value for the purpose of this Introduction. For, if the measure of civilization is the triumph of the mind over external agents, it becomes clear, that of the two classes of laws which regulate the progress of mankind, the mental class is more important than the physical. This, indeed, is assumed by one school of thinkers as a matter of course, though I am not aware that its demonstration has been hitherto attempted by any thing even approaching an exhaustive analysis. The question, however, as to the originality of my arguments, is one of very trifling moment; but what we have to notice is, that in the present stage of our inquiry, the problem with which we started has become simplified, and a discovery of the laws of European history is resolved, in the first instance, into a discovery of the laws of the human mind. These mental laws, when ascertained, will be the ultimate basis of the history of Europe; the physical laws will be treated as of minor importance, and as merely giving rise to disturbances, the force and the frequency of which have, during several centuries, perceptibly diminished.
If we now inquire into the means of discovering the laws of the human mind, the metaphysicians are ready with an answer; and they refer us to their own labours as supplying a satisfactory solution. It therefore becomes necessary to ascertain the value of their researches, to measure the extent of their resources, and, above all, to test the validity of that method which they always follow, and by which alone, as they assert, great truths can be elicited.
The metaphysical method, though necessarily branching into two divisions, is, in its origin, always the same, and consists in each observer studying the operations of his own mind.[285] This is the direct opposite of the historical method; the metaphysician studying one mind, the historian studying many minds. Now, the first remark to make on this is, that the metaphysical method is one by which no discovery has ever yet been made in any branch of knowledge. Every thing we at present know has been ascertained by studying phenomena, from which all casual disturbances having been removed, the law remains as a conspicuous residue.[286] And this can only be done by observations so numerous as to eliminate the disturbances, or else by experiments so delicate as to isolate the phenomena. One of these conditions is essential to all inductive science; but neither of them does the metaphysician obey. To isolate the phenomenon is for him an impossibility; since no man, into whatever state of reverie he may be thrown, can entirely cut himself off from the influence of external events, which must produce an effect on his mind, even when he is unconscious of their presence. As to the other condition, it is by the metaphysician set at open defiance; for his whole system is based on the supposition that, by studying a single mind, he can get the laws of all minds; so that while he, on the one hand, is unable to isolate his observations from disturbances, he, on the other hand, refuses to adopt the only remaining precaution—he refuses so to enlarge his survey as to eliminate the disturbances by which his observations are troubled.[287]
This is the first and fundamental objection to which metaphysicians are exposed, even on the threshold of their science. But if we penetrate a little deeper, we shall meet with another circumstance, which, though less obvious, is equally decisive. After the metaphysician has taken for granted that, by studying one mind, he can discover the laws of all minds, he finds himself involved in a singular difficulty as soon as he begins to apply even this imperfect method. The difficulty to which I allude is one which, not being met with in any other pursuit, seems to have escaped the attention of those who are unacquainted with metaphysical controversies. To understand, therefore, its nature, it is requisite to give a short account of those two great schools, to one of which all metaphysicians must necessarily belong.
In investigating the nature of the human mind, according to the metaphysical scheme, there are two methods of proceeding, both of which are equally obvious, and yet both of which lead to entirely different results. According to the first method, the inquirer begins by examining his sensations. According to the other method, he begins by examining his ideas. These two methods always have led, and always must lead, to conclusions diametrically opposed to each other. Nor are the reasons of this difficult to understand. In metaphysics, the mind is the instrument as well as the material on which the instrument is employed. The means by which the science must be worked out, being thus the same as the object upon which it works, there arises a difficulty of a very peculiar kind. This difficulty is, the impossibility of taking a comprehensive view of the whole of the mental phenomena; because, however extensive such a view may be, it must exclude the state of the mind by which, or in which, the view itself is taken. Hence we may perceive what, I think, is a fundamental difference between physical and metaphysical inquiries. In physics, there are several methods of proceeding, all of which lead to the same results. But in metaphysics, it will invariably be found, that if two men of equal ability, and equal honesty, employ different methods in the study of the mind, the conclusions which they obtain will also be different. To those who are unversed in these matters, a few illustrations will set this in a clearer light. Metaphysicians who begin by the study of ideas observe in their own minds an idea of space. Whence, they ask, can this arise? It cannot, they say, owe its origin to the senses, because the senses only supply what is finite and contingent; whereas the idea of space is infinite and necessary.[288] It is infinite, since we cannot conceive that space has an end; and it is necessary, since we cannot conceive the possibility of its non-existence. Thus far the idealist. But the sensualist, as he is called,[289]—he who begins, not with ideas, but with sensations, arrives at a very different conclusion. He remarks that we can have no idea of space until we have first had an idea of objects; and that the ideas of objects can only be the results of the sensations which those objects excite. As to the idea of space being necessary, this, he says, only results from the circumstance that we never can perceive an object which does not bear a certain position to some other object. This forms an indissoluble association between the idea of position and the idea of an object; and as this association is constantly repeated before us, we at length find ourselves unable to conceive an object without position, or, in other words, without space.[290] As to space being infinite, this, he says, is a notion we get by conceiving a continual addition to lines, or to surfaces, or to bulk, which are the three modifications of extension.[291] On innumerable other points we find the same discrepancy between the two schools. The idealist,[292] for example, asserts that our notions of cause, of time, of personal identity, and of substance, are universal and necessary; that they are simple; and that not being susceptible of analysis, they must be referred to the original constitution of the mind.[293] On the other hand, the sensationalist, so far from recognizing the simplicity of these ideas, considers them to be extremely complex, and looks upon their universality and necessity as merely the result of a frequent and intimate association.[294]
This is the first important difference which is inevitably consequent on the adoption of different methods. The idealist is compelled to assert, that necessary truths and contingent truths have a different origin.[295] The sensationalist is bound to affirm that they have the same origin.[296] The further these two great schools advance, the more marked does their divergence become. They are at open war in every department of morals, of philosophy, and of art. The idealists say that all men have essentially the same notion of the good, the true, and the beautiful. The sensationalists affirm that there is no such standard, because ideas depend upon sensations, and because the sensations of men depend upon the changes in their bodies, and upon the external events by which their bodies are affected.