Heeding neither squib, satire, nor sermon, Darwin, in the quiet of his Kentish home, went on rearranging old materials, collecting new materials, and verifying both, the outcome of this being his works on the Fertilization of Orchids and the Variation of Plants and Animals under Domestication, published in 1862 and 1867 respectively. Between these dates Huxley’s Man’s Place in Nature—logical supplement to the Origin of Species—appeared. But of this more anon.

Meanwhile, as already named, Mr. Patrick Matthew had in the Gardener’s Chronicle of 7th April, 1860, drawn attention to an appendix to his book on Naval Timber and Arboriculture published in 1831, in which he anticipated Darwin and Wallace’s theory as follows:

“The self-regulating adaptive disposition of organised life may, in part, be traced to the extreme fecundity of Nature, who, as before stated, has in all the varieties of her offspring a prolific power much beyond (in many cases a thousandfold) what is necessary to fill up the vacancies caused by senile decay. As the field of existence is limited and pre-occupied, it is only the hardier, more robust, better-suited-to-circumstance individuals, who are able to struggle forward to maturity, these inhabiting only the situations to which they have superior adaptation and greater power of occupancy than any other kind; the weaker and less circumstance-suited being prematurely destroyed. This principle is in constant action; it regulates the colour, the figure, the capacities, and instincts; those individuals in each species whose colour and covering are best suited to concealment or protection from enemies, or defence from inclemencies or vicissitudes of climate, whose figure is best accommodated to health, strength, defence, and support; whose capacities and instincts can best regulate the physical energies to self-advantage according to circumstances—in such immense waste of primary and youthful life those only come to maturity from the strict ordeal by which Nature tests their adaptation to her standard of perfection and fitness to continue their kind by reproduction” (pp. 384, 385).

While speaking of difficulty in understanding some passages in Mr. Matthew’s appendix, Darwin says that “the full force of the principle of natural selection” is there, and, in referring to it in a letter to Lyell, he adds that “one may be excused in not having discovered the fact in a work on Naval Timber!”

Five years after this, another pre-Darwinian was unearthed, and, like Patrick Matthew, in unsuspected company. Dr. W. C. Wells read a paper before the Royal Society in 1813 on a White Female Part of whose Skin resembles that of a Negro, but this was not published till 1818, when it formed part of a volume including the author’s famous Two Essays upon Dew and Single Vision. In his Historical Sketch Darwin says that Wells “distinctly recognises the principle of natural selection, and this is the first recognition which has been indicated; but he applies it only to the races of man, and to certain characters alone.... Of the accidental varieties of man, which would occur among the first few and scattered inhabitants of the middle regions of Africa, some one would be better fitted than the others to bear the diseases of the country. This race would consequently multiply, while the others would decrease; not only from their inability to sustain the attacks of disease, but from their incapacity of contending with their more vigorous neighbours.”

When the simplicity of the long-hidden solution is brought home, we can understand Huxley’s reflection on mastering the central idea of the Origin: “How extremely stupid not to have thought of that!” Twelve years elapsed before Darwin followed up his world-shaking book with the Descent of Man. But the ground had been prepared for its reception in the decade between 1860 and 1870. Quoting Grant Allen’s able summary of the advance of the theory of Evolution in his Charles Darwin: “One by one the few scientific men who still held out were overborne by the weight of evidence. Geology kept supplying fresh instances of transitional forms; the progress of research in unexplored countries kept adding to our knowledge of existing intermediate species and varieties. During those ten years, Herbert Spencer published his First Principles, his Biology, and the remodelled form of his Psychology; Huxley brought out Man’s Place in Nature, the Lectures on Comparative Anatomy, and the Introduction to the Classification of Animals; Wallace produced his Malay Archipelago and his Contributions to the Theory of Natural Selection (Bates, we may here add to Mr. Allen’s list, published his paper on Mimicry in 1861, and his Naturalist on the Amazons in 1863); and Galton wrote his admirable work on Hereditary Genius, of which his own family is so remarkable an instance. Tyndall and Lewes had long since signified their warm adhesion. At Oxford, Rolleston was bringing up a fresh generation of young biologists in the new faith; at Cambridge, Darwin’s old university, a whole school of brilliant and accurate physiologists was beginning to make itself both felt and heard. In the domain of anthropology, Tylor was welcoming the assistance of the new ideas, while Lubbock was engaged on his kindred investigations into the Origin of Civilization and the Primitive Condition of Man. All these diverse lines of thought both showed the widespread influence of Darwin’s first great work, and led up to the preparation of his second, in which he dealt with the history and development of the human race. And what was thus true of England was equally true of the civilized world, regarded as a whole: everywhere the great evolutionary movement was well in progress, everywhere the impulse sent forth from the quiet Kentish home was permeating and quickening the entire pulse of intelligent humanity.”

The Origin of Species, as we have seen, was intended as a rough draft or preliminary outline of the theory of natural selection. The materials which Darwin had collected in support of that theory being enormous, the several books which followed between 1859 and 1881, the year before his death, were expansions of hints and parts of the pioneer book. The last to appear was that treating of The Formation of Vegetable Mould through the Action of Worms. It embodied the results of experiments which had been carried on for more than forty years, since, as far back as 1837, Darwin read a paper on the subject before the Geological Society. Reference to it recalls a story, characteristic of Darwin’s innate modesty, told to the writer by the present John Murray. Darwin called on the elder Murray (presumably some time in 1880), and after fumbling in his coat-tail pocket, drew out a packet, which he handed to Murray with the timidity of an unfledged author submitting his first manuscript. “I have brought you,” he said, “a little thing of mine on the action of worms on soil,” and then paused as if in doubt whether Murray would care to run the risk of bringing out the book! One story leads to another, and our second relates to the burial of Darwin in Westminster Abbey. Among the signatures of members of Parliament, requesting Dean Bradley’s consent to Darwin’s interment there, was that of Mr. Richard B. Martin, partner in the well-known bank of that name, trading under the sign of the “Grasshopper.” In his history of this old institution Mr. John B. Martin prints the following letter, which was received on the 27th of April, 1882, the day after Darwin’s funeral.—

The accordance of a resting-place to Darwin’s remains among England’s illustrious dead in that Valhalla, was an irenicon from Theology to one whose theories, pushed to their logical issues, have done more than any other to undermine the supernatural assumptions on which it is built. Not that Darwin was a man of aggressive type. If he speaks on the high matters round which, like planet tethered to sun, the spirit of man revolves by irresistible attraction, it is with hesitating voice and with no deep emotion. A man of placid temper, in whom the observing faculties were stronger than the reflective, he was content to collect and co-ordinate facts, leaving to others the work of pointing out their significance, and adjusting them, as best they could, to this or that theory. It would be unjust to say of him what John Morley says of Voltaire, that “he had no ear for the finer vibrations of the spiritual voice,” but we know from his own confessions, what limitations hemmed in his emotional nature. The Life and Letters tells us that he was glad, after the more serious work and correspondence of the day were over, to listen to novels, for which he had a great love so long as they ended happily, and contained “some person whom one can thoroughly love, if a pretty woman, so much the better.” But strangely enough, he lost all pleasure in music, art, and poetry after thirty. When at school he enjoyed Thomson, Byron, and Scott; Shelley gave him intense delight, and he was fond of Shakespeare, especially the historical plays; but in his old age he found him “so intolerably dull that it nauseated me.”

It is often said that a man’s religion concerns himself only. So far as the value of the majority of people’s opinions on such high matters goes, this is true; but it is a shallow saying when applied to men whose words carry weight, or whose discoveries cause us to ask what is their bearing on the larger questions of human relations and destinies to which past ages have given answers that no longer satisfy us, or that are not compatible with the facts discovered. Whatever silence Darwin maintained in his books as to his religious opinions, intelligent readers would see that unaggressive as was the mode of presentments of his theory, it undermined current beliefs in special providence, with its special creations and contrivances, and therefore in the intermittent interference of a deity; thus excluding that supernatural action of which miracles are the decaying stock evidence.

Nor could they fail to ask whether the theory of natural selection by “descent with modification” was to apply to the human species. And when Darwin, already anticipated in this application by his more daring disciples, Professors Huxley and Haeckel, published his Descent of Man, with its outspoken chapter on the origin of conscience and the development of belief in spiritual beings, a belief subject to periodical revision as knowledge increased, it was obvious that the bottom was knocked out of all traditional dogmas of man’s fall and redemption, of human sin and divine forgiveness. Therefore, what Darwin himself believed was a matter of moment. His answers to inquiries which were made public during his lifetime told us that while the varying circumstances and modes of life caused his judgment to often fluctuate, and that while he had never been an atheist in the sense of denying the existence of a God, “I think,” he says, “that generally (and more and more as I grow older) but not always, an agnostic would be the most correct description of my state of mind.” The chapter on Religion, although a part of the autobiography, is printed separately in the Life and Letters. As the following quotation shows, it is interesting as detailing a few of the steps by which Darwin reached that suspensive stage.

Without doubt, the influence of the conclusions deducible from the theory of Evolution are fatal to belief in the supernatural. When we say the supernatural, we mean that great body of assumptions out of which are constructed all theologies, the essential element in these being the intimate relation between spiritual beings, of whom certain qualities are predicated, and man. These beings have no longer any place in the effective belief of intelligent and unprejudiced men, because they are found to have no correspondence with the ascertained operations of Nature.

2. Herbert Spencer.

Contact with many “sorts and conditions of men” brings home the need of ceaselessly dinning into their ears the fact that Darwin’s theory deals only with the evolution of plants and animals from a common ancestry. It is not concerned with the origin of life itself, nor with those conditions preceding life which are covered by the general term, Inorganic Evolution. Therefore, it forms but a very small part of the general theory of the origin of the earth and other bodies, “as the sand by the seashore innumerable,” that fill the infinite spaces.

We have seen that speculation about the universe had its rise in Ionia. After centuries of discouragement, prohibition, and, sometimes, actual persecution, it was revived, to advance, without further serious arrest, some three hundred years ago. A survey of the history of philosophies of the origin of the cosmos from the time of the renascence of inquiry, shows that the great Immanuel Kant has not had his due. As remarked already, he appears to have been the first to put into shape what is known as the nebular theory. In his General Natural History and Theory of the Celestial Bodies; or an Attempt to Account for the Constitution and the Mechanical Origin of the Universe upon Newtonian Principles, published in 1775, he “pictures to himself the universe as once an infinite expansion of formless and diffused matter. At one point of this he supposes a single centre of attraction set up, and shows how this must result in the development of a prodigious central body, surrounded by systems of solar and planetary worlds in all stages of development. In vivid language he depicts the great world-maelstrom, widening the margins of its prodigious eddy in the slow progress of millions of ages, gradually reclaiming more and more of the molecular waste, and converting chaos into cosmos. But what is gained at the margin is lost in the centre; the attractions of the central systems bring their constituents together, which then, by the heat evolved, are converted once more into molecular chaos. Thus the worlds that are lie between the ruins of the worlds that have been and the chaotic materials of the worlds that shall be; and in spite of all waste and destruction, Cosmos is extending his borders at the expense of Chaos.”

Kant’s speculations were confirmed by the celebrated mathematician, Laplace. He showed that the “rings” rotate in the same direction as the central body from which they were cast off; sun, planets, and moons (those of Uranus excepted) moving in a common direction, and almost in the same plane. The probability that these harmonious movements are the effects of like causes he calculated as 200,000 billions to one.

The observations of the famous astronomer, Sir William Herschel, which resulted in the discovery of binary or double stars, of star-clusters, and cloud-like nebulæ (as that term implies) were further confirmations of Kant’s theory. And such modifications in this as have been made by subsequent advance in knowledge, notably by the doctrine of the Conservation of Energy (the hypothesis of Kant and Laplace being based on gravitation alone), affect not the general theory of the origin of the heavenly bodies from seemingly formless, unstable, and highly-diffused matter. The assumption of primitive unstableness and unlikeness squares with the unequal distribution of matter; with the movements of its masses in different directions, and at different rates; and with the ceaseless redistribution of matter and motion. For all changes of states are due to the rearrangement of the atoms of which matter is made up, resulting in the evolution of the seeming like into the actual unlike; of the simple into the more and more complex, till—speaking of the only planet of whose life-history we can have knowledge—with the cooling of the earth to a temperature permitting of the evolution of living matter, the highest complexity is reached in the infinitely diverse forms of plants and animals. Therefore, as our knowledge of matter is limited to the changes of which we assume it to be the vehicle, it would seem that science reduces the Universe to the intelligible concept of Motion.

Since the great discovery by Kirchoff, in 1859, of the meaning of the dark lines that cross the refracted sun-rays, the spectroscope has come as powerful evidence in support of the nebular theory, while the photographic plate is a scarcely less important witness. The one has demonstrated that many nebulæ, once thought to be star-clusters, are masses of glowing hydrogen and nitrogen gases; that, to quote the striking communication made by the highest authority on the subject, Dr. Huggins, in his Presidential Address to the British Association, 1891, “in the part of the heavens within our ken, the stars still in the early and middle stages of evolution exceed greatly in number those which appear to be in an advanced condition of condensation.” The other, recording infallible vibrations on a sensitive plate, and securing accurate registration of the impressions, reveals, as in Dr. Roberts’s grand photograph of the nebula in Andromeda, a central mass round which are distinct rings of luminous matter, these being separated from the main body by dark rifts or spaces. To quote Dr. Huggins once more, “We seem to have presented to us some stage of cosmical Evolution on a gigantic scale.”

The great fact that lies at the back of all these confirmations of the nebular theory is the fundamental identity of the stuff of which the universe is made; a fact which entered into the prevision of the Ionian cosmologists. Dr. Huggins says that “if the whole earth were heated to the temperature of the sun, its spectrum would resemble very closely the solar spectrum.”

In referring to this, there may be carrying of “owls to Athens,” but that re-statements may sometimes be needful has illustration in Lord Salisbury’s Presidential Address to the British Association, 1894, wherein the assumed absence of oxygen and nitrogen in the sun’s spectrum is adduced as an argument against the theory of the common origin of the bodies of the solar system. Speaking of the predominant proportion of oxygen in the solid and liquid substances of the earth, and of the predominance of nitrogen in our atmosphere, his lordship asked, “if the earth be a detached bit whisked off the mass of the sun, as cosmogonists love to tell us, how comes it that, in leaving the sun, we cleaned him out so completely of his nitrogen and oxygen that not a trace of these gases remains behind to be discovered even by the searching vision of the spectroscope?” If Lord Salisbury had consulted Dr. Huggins, or some foreign astronomer of equal rank, as Dunér or Scheiner, he would not have put a question exposing his ignorance, and unmasking his prejudice. These authorities would have told him that when a mixture of the incandescent vapours of the metals and metalloids (or non-metallic elementary substances, to which class both oxygen and nitrogen belong), or their compounds, is examined with the spectroscope, the spectra of the metalloids always yield before that of the metals. Hence the absence of the lines of oxygen and other metalloids, carbon and silicon excepted, among the vast crowd of lines in the solar spectrum. Then, too, in extreme states of rarefaction of the sun’s absorbing layer, the absorption of the oxygen is too small to be sensible to us.

“While the genesis of the Solar System, and of countless other systems like it, is thus rendered comprehensible, the ultimate mystery continues as great as ever. The problem of existence is not solved: it is simply removed further back. The Nebular Hypothesis throws no light on the origin of diffused matter; and diffused matter as much needs accounting for as concrete matter. The genesis of an atom is not easier to conceive than the genesis of a planet. Nay, indeed, so far from making the universe a less mystery than before, it makes it a greater mystery. Creation by manufacture is a much lower thing than creation by evolution. A man can put together a machine; but he cannot make a machine develop itself. The ingenious artisan, able as some have been so far to imitate vitality as to produce a mechanical pianoforte player, may in some sort conceive how, by greater skill, a complete man might be artificially produced; but he is unable to conceive how such a complex organism gradually arises out of a minute structureless germ. That our harmonious universe once existed potentially as formless diffuse matter, and has slowly grown into its present organized state, is a far more astonishing fact than would have been its formation after the artificial method vulgarly supposed. Those who hold it legitimate to argue from phenomena to noumena, may rightly contend that the Nebular Hypothesis implies a First Cause as much transcending ‘the mechanical God of Paley’ as does the fetish of the savage.”

This quotation is from an essay on the Nebular Hypothesis, which appeared in the Westminster Review of July, 1858, and which must, therefore, have been written before the eventful date of the reading of Darwin and Wallace’s memorable paper before the Linnæan Society. The author of that essay is Mr. Herbert Spencer, and the foregoing extract from it may fitly preface a brief account of his life-work in co-ordinating the manifold branches of knowledge into a synthetic whole. In erecting a complete theory of Evolution on a purely scientific basis “his profound and vigorous writings,” to quote Huxley, “embody the spirit of Descartes in the knowledge of our own day.” Laying the foundation of his massive structure in early manhood, Mr. Spencer has had the rare satisfaction of placing the topmost stone on the building which his brain devised and his hand upreared. While the sheets of this little book are being passed for press, there arrives the third volume of the Principles of Sociology, which completes Mr. Spencer’s Synthetic Philosophy. In the preface to this, the venerable author says:

“On looking back over the six-and-thirty years which I have passed since the Synthetic Philosophy was commenced, I am surprised at my audacity in undertaking it, and still more surprised by its completion. In 1860 my small resources had been nearly all frittered away in writing and publishing books which did not repay their expenses; and I was suffering under a chronic disorder, caused by overtax of brain in 1855, which, wholly disabling me for eighteen months, thereafter limited my work to three hours a day, and usually to less. How insane my project must have seemed to onlookers, may be judged from the fact that before the first chapter of the first volume was finished, one of my nervous breakdowns obliged me to desist.

“But imprudent courses do not always fail. Sometimes a forlorn hope is justified by the event. Though, along with other deterrents, many relapses, now lasting for weeks, now for months, and once for years, often made me despair of reaching the end, yet at length the end is reached. Doubtless in earlier years some exultation would have resulted; but as age creeps on feelings weaken, and now my chief pleasure is in my emancipation. Still there is satisfaction in the consciousness that losses, discouragements, and shattered health have not prevented me from fulfilling the purpose of my life.”

These words recall a parallel invited by Gibbon’s record of his feelings on the completion of his immortal work, when walking under the acacias of his garden at Lausanne, he pondered on the “recovery of his freedom, and perhaps the establishment of his fame,” but with a “sober melancholy” at the thought that “he had taken an everlasting leave of an old and agreeable companion.”

Herbert Spencer, spiritual descendant—longo intervallo—of Heraclitus and Lucretius, was born at Derby on the 27th of April, 1820. His father was a schoolmaster; a man of scientific tastes, and, it is interesting to note, secretary of the Derby Philosophical Association founded by Erasmus Darwin. In Mr. Spencer’s book on Education there are hints of his inheritance of the father’s bent as an observer and lover of Nature in the remark that, “whoever has not in youth collected plants and insects, knows not half the halo of interest which lanes and hedgerows can assume.” He was articled in his seventeenth year to a railway engineer, and followed that profession until he was twenty-five. During this period he wrote various papers for the Civil Engineers’ and Architects’ Journal, and, what is of importance to note, a series of letters to the Nonconformist in 1842 on The Proper Sphere of Government (republished as a pamphlet in 1844), in which “the only point of community with the general doctrine of Evolution is a belief in the modifiability of human nature through adaptation to conditions, and a consequent belief in human progression.” After giving up engineering, Mr. Spencer joined the staff of the Economist, and while thus employed, published, in 1850, his first important book, Social Statics, or the Conditions essential to Human Happiness specified, and the first of them developed. In a footnote to the later editions of this work Mr. Spencer points out a brace of paragraphs in the chapter on General Considerations in which “may be seen the first step toward the general doctrine of Evolution. After referring to the analogy between the subdivision of labour, which goes on in human society as it advances; and the gradual diminution in the number of like parts and the multiplication of unlike parts which are observable in the higher animals; Mr. Spencer says:

“Now, just the same coalescence of like parts and separation of unlike ones—just the same increasing subdivision of function—takes place in the development of society. The earliest social organisms consist almost wholly of repetitions of one element. Every man is a warrior, hunter, fisherman, builder, agriculturist, toolmaker. Each portion of the community performs the same duties with every other portion; much as each slice of the polyp’s body is alike stomach, muscle, skin, and lungs. Even the chiefs, in whom a tendency towards separateness of function first appears, still retain their similarity to the rest in economic respects. The next stage is distinguished by a segregation of these social units into a few distinct classes—warriors, priests, and slaves. A further advance is seen in the sundering of the labourers into different castes, having special occupations, as among the Hindoos. And, without further illustration, the reader will at once perceive, that from these inferior types of society up to our own complicated and more perfect one, the progress has ever been of the same nature. While he will also perceive that this coalescence of like parts, as seen in the concentration of particular manufactures in particular districts, and this separation of agents having separate functions, as seen in the more and more minute division of labour, are still going on.

“Thus do we find, not only that the analogy between a society and a living creature is borne out to a degree quite unsuspected by those who commonly draw it, but also that the same definition of life applies to both. This union of many men into one community—this increasing mutual dependence of units which were originally independent—this formation of a whole consisting of unlike parts—this growth of an organism, of which one portion cannot be injured without the rest feeling it—may all be generalized under the law of individuation. The development of society, as well as the development of man and the development of life generally, may be described as a tendency to individuate—to become a thing. And rightly interpreted, the manifold forms of progress going on around us are uniformly significant of this tendency.”

Homo sum: humani nihil a me alienum puto: “I am a man and nothing human is foreign to me.” This oft-quoted saying of the old farmer in the Self-Tormentor of Terence might be affixed as motto to Herbert Spencer’s writings from the tractate on the Proper Sphere of Government to the concluding volume of the Principles of Sociology. For thought of human interests everywhere pervades them; social and ethical questions are kept in the van throughout. Philosophy is brought from her high seat to mix in the sweet amenities of home, in the discipline of camp, in the rivalry of market; and linked to conduct. Conduct is defined as “acts adjusted to ends,” the perfecting of the adjustment being the highest aim, so that “the greatest totality of life in self, in offspring, and in fellow-men” is secured, the limit of evolution of conduct not being reached, “until, beyond avoidance of direct and indirect injuries to others, there are spontaneous efforts to further the welfare of others.” Emerson puts this ideal into crisp form when he speaks of the time in which a man shall care more that he wrongs not his neighbour than that his neighbour wrongs him; then will his “market-cart become a chariot of the sun.”

That humanity is the pivot round which Mr. Spencer’s philosophic system revolves is seen in the earliest Essays, and notably in his making mental evolution the subject of the first instalment of his Synthetic Philosophy. For, in the Principles of Psychology, published in 1855, he limits feeling or consciousness to animals possessing a nervous system, and traces its beginnings in the “blurred, undetermined feeling answering to a single pulsation or shock” (as for example, to go no lower down the life-scale, in the medusa or jelly-fish), to its highest form as self-consciousness, or knowing that we know, in man. This dominant element in Mr. Spencer’s philosophy secures it a life and permanence which, had it been restricted to explaining the mechanics of the inorganic universe, it could never have possessed. It has been observed how the Darwinian theory aroused attention in all quarters because it touched human interests on every side. And, although less obvious to the multitude, the Synthetic Philosophy, dealing with all cosmic processes as purely mechanical problems, interprets “the phenomena of life (excluding the question of its origin), mind, and society, in terms of matter and motion.” Anticipating the levelling of epithets against such apparent materializing of mental phenomena involved in that method, Spencer remarks on the dismay with which men, who have not risen above the vulgar conception which unites with matter the contemptuous epithets “gross” and “brute,” regard the proposal to reduce the phenomena of Life, of Mind, and of Society, to a level which they think so degraded. “Whoever remembers that the forms of existence which the uncultivated speak of with so much scorn, are shown by the man of science to be the more marvellous in their attributes the more they are investigated, and are also proved to be in their ultimate natures absolutely incomprehensible—as absolutely incomprehensible as sensation, or the conscious something which perceives it—whoever clearly recognises this truth, will see that the course proposed does not imply a degradation of the so-called higher, but an elevation of the so-called lower. Perceiving, as he will, that the Materialist and Spiritualist controversy is a mere war of words,—in which the disputants are equally absurd, each thinking that he understands that which it is impossible for any man to understand,—he will perceive how utterly groundless is the fear referred to. Being fully convinced that no matter what nomenclature is used, the ultimate mystery must remain the same, he will be as ready to formulate all phenomena in terms of Matter, Motion, and Force, as in any other terms; and will rather indeed anticipate, that only in a doctrine which recognises the Unknown Cause as co-extensive with all orders of phenomena, can there be a consistent Religion, or a consistent Philosophy.”

This is clear enough; yet such is the crass density of some objectors that eighteen years after the above was written, Mr. Spencer, in answering criticisms on First Principles, had to rebut the charge that he believed matter to consist of “space-occupying units, having shape and measurement.”

The Principles of Psychology was both preceded and followed by a series of essays in which the process of change from the “homogeneous to the heterogeneous,” i. e., from the seeming like to the actual unlike, was expounded. Mr. Spencer tells us that in 1852 he first became acquainted with Von Baer’s Law of Development, or the changes undergone in each living thing, from the general to the special, during its advance from the embryonic to the fully-formed state. That law confirmed the prevision indicated in the passages quoted above from Social Statics, and impressed him as one of the three doctrines which are indispensable elements of the general theory of Evolution. The other two are the Correlation of the Physical Forces, or the transformation of different modes of motion into other modes of motion, as of heat or light into electricity, and so forth, in Proteus-like fashion; and the Conservation of Energy, or the indestructibility of matter and motion, whatever changes or transformations these may undergo.

In permitting the quotation of the useful abstract of the Synthetic Philosophy which, originally drawn up for the late Professor Youmans, was imbodied in a letter to the Athenæum of 22d of July, 1882, Mr. Spencer was good enough to volunteer the following details to the writer:—

“You are probably aware that the conception set forth in that abstract was reached by slow steps during many years. These steps occurred as follows:—

“From these last two Essays came the inception of the Synthetic Philosophy. The first programme of it was drawn up in January, 1858.” ...

When seeing Mr. Spencer on the subject of this letter, he took the further trouble to point out certain passages in the essays originally comprised in the one volume edition of 1858 which contain germinal ideas of his synthesis. That they are his selection will add to the interest and value of their quotation, revealing, as perchance they may, a fragment of the autobiography which it is an open secret Mr. Spencer has written.

“That Law, Religion, and Manners are thus related—that their respective kinds of operation come under one generalisation—that they have in certain contrasted characteristics of men a common support and a common danger—will, however, be most clearly seen on discovering that they have a common origin. Little as from present appearances we should suppose it, we shall yet find that at first, the control of religion, the control of laws, and the control of manners, were all one control. However incredible it may now seem, we believe it to be demonstrable that the rules of etiquette, the provisions of the statute-book, and the commands of the decalogue, have grown from the same root. If we go far back enough into the ages of primeval Fetishism, it becomes manifest that originally Deity, Chief, and Master of the Ceremonies were identical” (Essays, vol. i, 1883 edition; Manners and Fashion, p. 65).

“Scientific advance is as much from the special to the general as from the general to the special. Quite in harmony with this we find to be the admissions that the sciences are as branches of one trunk, and that they were at first cultivated simultaneously; and this becomes the more marked on finding, as we have done, not only that the sciences have a common root, but that science in general has a common root with language, classification, reasoning, art; that throughout civilisation these have advanced together, acting and reacting on each other just as the separate sciences have done; and that thus the development of intelligence in all its divisions and subdivisions has conformed to this same law to which we have shown the sciences conform” (Ib. The Genesis of Science, pp. 191, 192).

(In correspondence with this, recognising that the same method has to be adopted in all inquiry, whether we deal with the body or the mind, the following may be quoted from Hume’s Treatise on Human Nature.

“’Tis evident that all the sciences have a relation, greater or less, to human nature; and that, however wide any of them may seem to run from it, they still return back by one passage or another. Even Mathematics, Natural Philosophy, and Natural Religion are in some measure dependent on the science of Man, since they lie under the cognisance of men, and are judged of by their powers and qualities.)

“The analogy between individual organisms and the social organisms is one that has in all ages forced itself on the attention of the observant.... While it is becoming clear that there are no such special parallelisms between the constituent parts of a man and those of a nation, as have been thought to exist, it is also becoming clear that the general principles of development and structure displayed in all organised bodies are displayed in societies also. The fundamental characteristic both of societies and of living creatures is, that they consist of mutually dependent parts; and it would seem that this involves a community of various other characteristics.... Meanwhile, if any such correspondence exists, it is clear that Biology and Sociology will more or less interpret each other.

“One of the positions we have endeavoured to establish is, that in animals the process of development is carried on, not by differentiations only, but by subordinate integrations. Now in the social organism we may see the same duality of process; and further, it is to be observed that the integrations are of the same three kinds. Thus we have integrations that arise from the simple growth of adjacent parts that perform like functions; as, for instance, the coalescence of Manchester with its calico-weaving suburbs. We have other integrations that arise when, out of several places producing a particular commodity, one monopolises more and more of the business, and leaves the rest to dwindle; as witness the growth of the Yorkshire cloth districts at the expense of those in the west of England.... And we have yet those other integrations that result from the actual approximation of the similarly-occupied parts, whence results such facts as the concentration of publishers in Paternoster Row, of lawyers in the Temple and neighbourhood, of corn merchants about Mark Lane, of civil engineers in Great George Street, of bankers in the centre of the city” (Essays, vol. iii, 1878 edition; Transcendental Physiology, pp. 414-416).

But, divested of technicalities, and summarized in words to be “understanded of the people,” the following quotation from the Essay on Progress: Its Law and Cause, gives the gist of the Synthetic Philosophy:

“We believe we have shown beyond question that that which the German physiologists (Von Baer, Wolff, and others) have found to be the law of organic development (as of a seed into a tree, and of an egg into an animal), is the law of all development. The advance from the simple to the complex, through a process of successive differentiations (i. e., the appearance of differences in the parts of a seemingly like substance), is seen alike in the earliest changes of the Universe to which we can reason our way back; and in the earlier changes which we can inductively establish; it is seen in the geologic and climatic evolution of the Earth, and of every single organism on its surface; it is seen in the evolution of Humanity, whether contemplated in the civilised individual, or in the aggregation of races; it is seen in the evolution of Society in respect alike of its political, its religious, and its economical organisation; and it is seen in the evolution of all those endless concrete and abstract products of human activity which constitute the environment of our daily life. From the remotest past which Science can fathom, up to the novelties of yesterday, that in which Progress essentially consists, is the transformation of the homogeneous into the heterogeneous” (Essays, vol. i, 1883, p. 30).

To this may fitly follow the “succinct statement of the cardinal principles developed in the successive works,” which Mr. Spencer, as named above, prepared for Professor Youmans.

1. Throughout the universe in general and in detail there is an unceasing redistribution of matter and motion.

2. This redistribution constitutes evolution when there is a predominant integration of matter and dissipation of motion, and constitutes dissolution when there is a predominant absorption of motion and disintegration of matter.

3. Evolution is simple when the process of integration, or the formation of a coherent aggregate, proceeds uncomplicated by other processes.

4. Evolution is compound, when along with this primary change from an incoherent to a coherent state, there go on secondary changes due to differences in the circumstances of the different parts of the aggregate.

5. These secondary changes constitute a transformation of the homogeneous into the heterogeneous—a transformation which, like the first, is exhibited in the universe as a whole and in all (or nearly all) its details; in the aggregate of stars and nebulæ; in the planetary system; in the earth as an inorganic mass; in each organism, vegetal or animal (Von Baer’s law otherwise expressed); in the aggregate of organisms throughout geologic time; in the mind; in society; in all products of social activity.

6. The process of integration, acting locally as well as generally, combines with the process of differentiation to render this change not simply from homogeneity to heterogeneity, but from an indefinite homogeneity to a definite heterogeneity; and this trait of increasing definiteness, which accompanies the trait of increasing heterogeneity, is, like it, exhibited in the totality of things and in all its divisions and subdivisions down to the minutest.

7. Along with this redistribution of the matter composing any evolving aggregate there goes on a redistribution of the retained motion of its components in relation to one another; this also becomes, step by step, more definitely heterogeneous.

8. In the absence of a homogeneity that is infinite and absolute, that redistribution, of which evolution is one phase, is inevitable. The causes which necessitate it are these—

9. The instability of the homogeneous, which is consequent upon the different exposures of the different parts of any limited aggregate to incident forces.

The transformations hence resulting are—

10. The multiplication of effects. Every mass and part of a mass on which a force falls subdivides and differentiates that force, which thereupon proceeds to work a variety of changes; and each of these becomes the parent of similarly-multiplying changes; the multiplication of them becoming greater in proportion as the aggregate becomes more heterogeneous. And these two causes of increasing differentiations are furthered by—

11. Segregation, which is a process tending ever to separate unlike units and to bring together like units—so serving continually to sharpen, or make definite, differentiations otherwise caused.

12. Equilibration is the final result of these transformations which an evolving aggregate undergoes. The changes go on until there is reached an equilibrium between the forces which all parts of the aggregate are exposed to and the forces these parts oppose to them.

Equilibration may pass through a transition stage of balanced motions (as in a planetary system) or of balanced functions (as in a living body) on the way to ultimate equilibrium; but the state of rest in inorganic bodies, or death in organic bodies, is the necessary limit of the changes constituting evolution.

13. Dissolution is the counter-change which sooner or later every evolved aggregate undergoes. Remaining exposed to surrounding forces that are unequilibrated, each aggregate is ever liable to be dissipated by the increase, gradual or sudden, of its contained motion; and its dissipation, quickly undergone by bodies lately animate, and slowly undergone by inanimate masses, remains to be undergone at an indefinitely remote period by each planetary and stellar mass, which since an indefinitely distant period in the past has been slowly evolving; the cycle of its transformations being thus completed.

14. This rhythm of evolution and dissolution, completing itself during short periods in small aggregates, and in the vast aggregates distributed through space completing itself in periods immeasurable by human thought, is, so far as we can see, universal and eternal—each alternating phase of the process predominating now in this region of space and now in that, as local conditions determine.

15. All these phenomena, from their great features down to their minutest details, are necessary results of the persistence of force under its forms of matter and motion. Given these as distributed through space, and their quantities being unchangeable, either by increase or decrease, there inevitably result the continuous redistributions distinguishable as evolution and dissolution, as well as all these special traits above enumerated.

16. That which persists unchanging in quantity, but ever changing in form, under these sensible appearances which the universe presents to us, transcends human knowledge and conception—is an unknown and unknowable power, which we are obliged to recognise as without limit in space and without beginning or end in time.

All that is comprised in the dozen volumes which, exclusive of the minor works and the Sociological Tables, form the great body of the Synthetic Philosophy, is the expansion of this abstract. The general lines laid down in that Philosophy have become a permanent way along which investigation will continue to travel. The revisions which may be called for will not affect it fundamentally, being limited to details, more especially in the settlement of the relative functions of individuals and communities, and cognate questions. Into these we cannot enter here. Suffice it, that to those who have the rare possession of sound mental peptics, no more nutritive diet can be recommended than is supplied by First Principles and the works in which its theses are developed. For those who, blessed with good digestion, lack leisure, there is provided in a convenient volume the excellent epitome which Mr. Howard Collins has prepared.

The prospectus of the then proposed issue of the series of works which, beginning with First Principles, ends with the Principles of Sociology (1862-1896), was issued by Mr. Spencer in March, 1860. Through his courtesy the writer has seen the documents which prove that the first draft of that prospectus was written out on the 6th of January, 1858, and that it was the occasion of an interesting correspondence between Mr. Spencer and his father—mainly in the form of questions from the latter—during that month. The record of these facts is of some moment as evidencing that the scheme of the Synthetic Philosophy took definite shape in 1857. Therefore, the Theory of Evolution, dealing with the universe as a whole, was formulated some months before the publication of the Darwin-Wallace paper, in which only organic evolution was discussed. The Origin of Species, as the outcome of that paper, showed that the action of natural selection is a sufficing cause for the production of new life-forms, and thus knocked the bottom out of the old belief in special creation.

The general doctrine of Evolution, however, is not so vitally related to that of natural selection that the two stand or fall together. The evidence as to the connection between the succession of past life-forms which, regard being had to the well-nigh obliterated record, has been supplied by the fossil-yielding rocks; and the evidence as to the unbroken development of the highest plants and animals from the lowest which more and more confirms the theory of Von Baer; alike furnish a body of testimony placing the doctrine of Organic Evolution on a foundation that can never be shaken. And, firm as that, stands the doctrine of Inorganic Evolution upon the support given by modern science to the speculations of Immanuel Kant.

There is the more need for laying stress on this because recent discussions, revealing divided opinions among biologists as to the sufficiency of natural selection as a cause of all modifications in the structure of living things, lead timid or half-informed minds to hope that the doctrine of Evolution may yet turn out not to be true. It is in such stratum of intelligence that there lurks the feeling, whenever some old inscription or monument verifying statements in the Bible is discovered, that the infallibility of that book has further proof. For example, until the present year, not a single confirmatory piece of evidence as to the story of the Exodus was forthcoming from Egypt itself. Even the inscription which has come to light does not, in the judgment of such an expert as Dr. Flinders Petrie, supply the exact confirmation desired. But let that irrefragable witness appear, and while the historian will welcome it as evidence of the sojourn of the Israelites in Egypt, thus throwing light on the movements of races, and adding to the historical value of the Pentateuch; the average orthodox believer will feel a vague sort of satisfaction that the foundations of his belief in the Trinity and the Incarnation are somehow strengthened.