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.”