of this correspondence. Commencing with the lowest types of life, Mr. Spencer, in successive chapters, traces up this relation of correspondence as extending in space and time, as increasing in specialty, in generality, and in complexity. It is also shown that the correspondence progresses from a more homogeneous to a more heterogeneous form, and that it becomes gradually more integrated-the terms here employed, in respect to the Evolution of mind, being the terms subsequently used in treating of Evolution in general. In the fourth part of the work, under the title of "Special Synthesis," the Evolution is traced out under its concrete form from reflex action up through instinct, memory, reason, feelings, and the will. Mr. Spencer here distinctly avowed his belief that "Life, in its multitudinous and infinitely varied embodiments, has arisen out of the lowest and simplest beginnings, by steps as gradual as those which evolve a homogeneous microscopic germ into a complex organism "-dissent being, at the same time, expressed from that version of the doctrine put forth by the author of the "Vestiges of the Natural History of Creation." It was, moreover, shown by subjective analysis how intelligence may be resolved, step by step, from its most complex into its simplest elements; and it was also proved that there is "unity of composition" throughout, and that thus mental structure, contemplated internally, harmonizes with the doctrine of Evolution.

It was at this time (1854), as I have been informed by Mr. Spencer, when he had been at work upon the "Principles of Psychology" not more than two months, that the general conception of Evolution in its causes and extent, as well as its processes, was arrived at. He had somewhat earlier conceived of it as universally a transformation from the homogeneous into the heterogeneous. This kind of change which Von Baer had shown to take place in every individual organism, as it develops, Mr. Spencer had already traced out as taking place in the progress of social arrangements, in the development of the sciences, and now in the Evolution of mind in general from the lower forms to the higher. And the generalization soon extended itself so as to embrace the transformations undergone by all things inanimate as well as animate. This universal extension of the idea led rapidly to the conception of a universal cause necessitating it. In the autumn of 1854, Mr. Spencer proposed to the editor of the Westminster Review to write an article upon the subject under the title of "The Cause of all Progress," which was objected to as being too assuming. The article was, however, at that time agreed upon, with the understanding that it should be written as soon as the "Principles of Psychology" was finished. The agreement was doomed to be defeated, however, so far as the date was concerned, for, along with the completion of the "Psychology," in July, 1855, there came a nervous break-down, which incapacitated Mr. Spencer for labor during a period of eighteen months —the whole work having been written in less than a year.

We may here note Mr. Spencer's advanced position in dealing with this subject. While yet the notion of Evolution as a process of Nature was as vague and speculative as it had been in the time of Anaximander and Democritus, he had grasped the problem in its universality and its causes, and had successfully applied it to one of the most difficult and important of the sciences. He had traced the operation of the law in the sphere of mind, and placed that study upon a new basis. The conviction is now entertained by many that the "Principles of Psychology," by Spencer, in 1855, is one of the most original and masterly scientific treatises of the present century, if, indeed, it be not the most fruitful contribution to scientific thought that has appeared since the "Principia" of Newton.' For thousands of years, from Plato to Hamilton, the world's ablest thinkers had been engaged in the effort to elucidate the phenomena of mind; Herbert Spencer took up the question by a method first rendered possible by modern science, and made a new epoch in its progress. From this time forward, mental philosophy, so called, could not confine itself to introspection of the adult human consciousness. The philosophy of mind must deal with the whole range of psychical phenomena, must deal with them as manifestations of organic life, must deal with them genetically, and show how mind is constituted in connection with the experience of the past. In short, as it now begins to be widely recognized, Mr. Spencer has placed the science of mind firmly upon the ground of Evolution. Like all productions that are at the same time new and profound, and go athwart the course of long tradition, there were but few that appreciated his book, a single small edition more than sufficing to meet the wants of the public for a dozen years. But it began at once to tell upon advanced thinkers, and its influence was soon widely discerned in the best literature of the subject. The man who stood, perhaps, highest in England as a psychologist, Mr. John Stuart Mill, remarked in one of his books, that "it is one of the finest examples we possess of the psychological method in its full power;" and, as I am aware, after carefully rereading it some years later, he declared that his already high opinion of the work had been raised

1 This association of the name of Spencer with Newton, let it be remembered, does not rest upon the authority of the present writer; recent discussions of the subject in the highest quarters are full of it. The Saturday Review says, "Since Newton there has not in England been a philosopher of more remarkable speculative and systematizing talent than (spite of some errors and some narrowness) Mr. Herbert Spencer." An able writer in the Quarterly Review, in treating of Mr. Spencer's remarkable power of binding together different and distant subjects of thought by the principle of Evolution, remarks: "The two deepest scientific principles now known of all those relating to material things are the Law of Gravitation and the Law of Evolution." The eminent Professor of Logic in Owens College, Manchester, Mr. W. Stanley Jevons, in his recent treatise entitled "The Principles of Science, a Treatise on Logic and Scientific Method,” says, “I question whether any scientific works which have appeared, since the 'Principia' of Newton, are comparable in importance with those of Darwin and Spencer, revolutionizing as they do all our views of the origin of bodily, mental, moral, and social phenomena."

still more which he recognized as due to the progress of his own mind.

The article "Progress, its Law and Cause," projected, as we have seen, in 1854, was written early in 1857. In the first half of it the transformation of the homogeneous into the heterogeneous is traced throughout all orders of phenomena; in the second half the principle of transformation is deduced from the law of the multiplication of effects. In this essay, moreover, there is indicated the application of the general law of Evolution to the production of species. It is shown that there "would not be a substitution of a thousand more or less modified species for the thousand original species; but, in place of the thousand modified species, there would arise several thousand species, or varieties, or changed forms;" and that "each original race of organisms would become the root from which diverged several races differing more or less from it and from each other." It is further argued that the new relations in which animals would be placed toward one another would initiate further differences of habit and consequent modifications, and that "there must arise, not simply a tendency toward the differentiations of each race of organisms into several races, but also a tendency to the occasional production of a somewhat higher organism." The case of the divergent varieties of man, some of them higher than others, caused in this same manner, is given in illustration. Throughout the argument there is a tacit implication that, as a consequence of the cause of Evolution, the production of species will go on, not in ascending linear series, but by perpetual divergence and redivergence-branching and again branching. The general conception, however, differs from that of Mr. Darwin in this that adaptation and readaptation to continually-changing conditions is the only process recognized-there is no recognition of "spontaneous variations," and the natural selection of those that are favorable.

During the summer of 1857 Mr. Spencer wrote the "Origin and Function of Music," published in Fraser's Magazine for October. Like nearly all of his other writings, this interesting article is dominated by the idea of Evolution. The general law of nervo-motor action in all animals is shown to furnish an explanation of the tones and cadences of emotional speech; and it is pointed out that from these music is evolved by simple exaltation of all the distinctive traits, and carrying them out into ideal combination. A further step was taken, the same year, in the development of the doctrine of Evolution, which is indicated in the article entitled "Transcendental Physiology." It was there explained that the multiplication of effects was not the only cause of the universal change from homogeneity to heterogeneity, but that there was an antecedent principle to be recog nized, viz., the Instability of the Homogeneous. The physiological illustrations of the law are mainly dwelt upon, though its other applications are indicated.

In October of the same year, the essay on "Representative Government-what is it good for?" appeared in the Westminster Review. The law of progress is here applied to the interpretation of state functions, and it is stated that the specialization of offices, "as exhibited in the Evolution of living creatures, and as exhibited in the Evolution of societies," holds throughout; that "the governmental part of the body politic exemplifies this truth equally with its other parts." In January, 1858, the essay on "State Tamperings with Money and Banks" appeared in the same periodical. The general doctrine of the limitations of state functions is there reaffirmed, with further illustration of the mischiefs that arise from traversing the normal laws of life; and it is contended that "the ultimate result of shielding men' from the effects of folly is to fill the world with fools"—an indirect way of asserting the beneficial effects of the survival of the fittest.

In April, 1858, Mr. Spencer published an essay on "Moral Education," in the British Quarterly Review, and throughout the argument every thing is again regarded from the Evolution point of view. The general truth insisted upon is, that the natural rewards and restraints of conduct are those which are most appropriate and effectual in modifying character. The principle contended for is, that the moral education of every child should be regarded as an adaptation of its nature to the circumstances of life; and that to become adapted to these circumstances it must be allowed to come in contact with them; must be allowed to suffer the pains and obtain the pleasures which do in the order of Nature follow certain kinds of action. There is here, in fact, applied to actual life, the general conception of the nature of life, previously inculcated in the "Principles of Psychology"—a correspondence between the inner and the outer actions that becomes great in proportion as the converse with outer actions through experience becomes extended.

The essay on the "Nebular Hypothesis" was published in the Westminster Review for July, 1858. The opinion was then almost. universally held that the nebular hypothesis had been exploded, and the obvious bearing of the question upon the theory of Evolution induced Mr. Spencer to take it up. The conclusions that had been drawn from observations with Lord Rosse's telescope, that the nebular hypothesis had been invalidated, were shown to be erroneous; and the position taken, that the nebulæ could not be (as they were then supposed to be) remote sidereal systems, has been since verified. Spectrum analysis has, in fact, proved what Mr. Spencer then maintained, that there are many nebula composed of gaseous matter. To the various indications of the nebular origin of our own solar system commonly given, others were added which had not been previously recognized, while the view that Mr. Spencer took of the constitution of the solar atmosphere has since been also verified by spectrum analysis.

VOL. VI.-3

In October, 1858, he published in the Medico-Chirurgical Review a criticism on Prof. Owen's " Archetype and Homologies of the Vertebrate Skeleton," which was written in furtherance of the doctrine of Evolution, and to show that the structural peculiarities which are not accounted for on the theory of an archetypal vertebra, are accounted for on the hypothesis of development. In January of the next year, there appeared in the same review a paper on The Laws of Organic Form," already referred to, the germ of which dated back to 1851, and which was a further elucidation of the doctrine of Evolution, by showing the direct action of incident forces in modifying the forms of organisms and their parts. In April, 1859, appeared in the British Quarterly Review an article on "Physical Education," in which the bearing of biological principles upon the management of children in respect to their bodily development is considered. It insists upon the normal course of unfolding, versus those hindrances to it which ordinary school regulations impose; it asserts the worth of the bodily appetites and impulses in children, which are commonly so much thwarted; and contends that during this earlier portion of life, in which the main thing to be done is to grow and develop, our educational system is too exacting-" it makes the juvenile life far more like the adult life than it should be." The essay "What Knowledge is of most Worth" was printed in the Westminster Review for July, 1859. This argument is familiar to the public, as it has been many times republished, but what is here most worthy of note is that, in criticising the current study of history, it defines with great distinctness the plan of the "Descriptive Sociology," the first divisions of which are now just published, and form the comprehensive and systematic data upon which the Principles of Sociology are to be based.

An argument on "Illogical Geology" was contributed in July, 1859, to the Universal Review, which, although nominally a criticism. of Hugh Miller, was really an attack upon the prevalent geological doctrine which asserted simultaneity in the systems of strata in different parts of the earth. His view, which was at that time heresy, is now coming into general recognition. In the Medico-Chirurgical Review for January, 1860, Mr. Spencer published a criticism on Prof. Bain's work, "The Emotions and the Will," designed to show that the emotions cannot be properly understood and classified without studying them from the point of view of Evolution, and tracing them up through their increasing complications from lower types of animals to higher. The essay on the "Social Organism" appeared at the same time in the Westminster Review, in which it was maintained that society, consisting of an organized aggregate, follows the same course of Evolution with all other organized aggregates-increasing in mass and showing a higher integration not only in this respect but also in its growing solidarity; becoming more and more heterogeneous in all its structures and more and more definite in all its differentiations. The