CHAPTER IX.

THE RELATION OF EVOLUTION TO THE PROBLEM OF EVIL.

The problem of evil has tasked the power and baffled the skill of the greatest thinkers in every age. It would be folly in me to imagine that I can solve it. Its complete solution is probably impossible in the present state of science. Yet I can not doubt that on this, as on every important question relating to man, the theory of evolution will throw new and important light. All I can hope to do is to throw out some brief suggestions on the subject.

If evolution be true, and especially if man be indeed a product of evolution, then what we call evil is not a unique phenomenon confined to man, and the result of an accident, but must be a great fact pervading all nature, and a part of its very constitution. It must have existed in all time in different forms, and subject like all else to the law of evolution. Let us, then, trace rapidly some of the steps of this evolution.

1. _External Physical Evil in the Animal Kingdom._--As already seen in previous chapters, the necessary condition of evolution of the organic kingdom is a _struggle_ for life--a conflict on every side, with a seemingly _inimical_ environment and a survival of only the strongest, the swiftest, or the most cunning--in a word, the fittest. Now, suppose the course of organic evolution finished in the introduction of man, and from this vantage-ground we look back over the course and consider its result. Shall we call that evil which was the necessary condition of the progressive elevation which culminated so gloriously? Evil doubtless it seemed to the individual, struggling animal, but is this worthy to be weighed in comparison with the evolution of the whole organic kingdom until it culminated in man? Is it not rather a _good_ in disguise? I suppose human arrogance may be willing enough to admit it in _this_ case, where animals only are sufferers.

2. _Physical Evil in Relation to Man._--But organic evolution, completed in man, was immediately transferred to a higher plane, and continued as social evolution; material evolution is transformed into psychical evolution; unconscious evolution, according to _necessary_ law, to conscious voluntary progress toward a recognized goal, and according to a _freer_ law. But in this transformation the fundamental conditions of evolution do not change. Man also is surrounded on every side with what at first seems to him an _evil environment_, against which he must ever struggle or perish. Heat and cold, tempest and flood, volcanoes and earthquakes, savage beasts and still more savage men. What is the remedy--the only conceivable remedy? Knowledge of the laws of Nature, and thereby acquisition of power over Nature. But increasing knowledge and power are equivalent to progressive elevation in the scale of psychical being. This conflict with what seems an evil environment is, therefore, the necessary condition of such elevation. It is not too much to say that, without this condition, except for this necessity for struggle, man could never have emerged out of animality into humanity, or, having thus emerged, would never have risen above the lowest possible stage. Now suppose, again, this ideal to have been attained--suppose knowledge of physical laws and power over physical forces to be complete--suppose physical nature completely subdued, put beneath our feet, and subject to our will, and, from the high intellectual position thus attained, we look back over the whole ground and consider the result. Shall that be called evil which was obviously the necessary condition for attaining our then elevated position? Evil it doubtless seemed to the individuals who fell, and still seems to us who now suffer, by the way in the conflict; but is physical discomfort or even physical death of the individual to be weighed in comparison with the psychical elevation of the individual, and especially of the race? Evidently, then, physical evil even in the case of man is only _seeming_ evil, but _real_ good.

3. _Organic Evil--Disease._--But there is a more dreadful form of evil than that which results from _external_ physical nature--an evil far more subtle and difficult to understand, and therefore to conquer. I mean _internal_ organic evil--disease in its diversified forms and with its attendant weakness and suffering, inscrutable often in its causes, insidious in its approaches, contagious, infectious, spreading from house to house, carrying suffering and death in its course, and leaving sorrow and desolation behind. Is there any remedy which can transmute this evil into good? There is. It is again knowledge--knowledge of the laws, and power over the forces, of _organic nature_. Is it not evident that complete knowledge of the laws of health and the causes of disease would put this evil also under our feet? Is it not evident that a perfect knowledge of the laws of health, and a perfect living according to these laws, would so entirely subdue this evil that men would no longer die except by natural decay or by accident? Is it not evident, also, that the race will not attain this knowledge unless it be forced upon us by the necessity of avoiding the dread evil of disease?

Now suppose, again, this ideal attained, suppose this dread evil subdued by complete knowledge, and again from our elevated intellectual position we look back over the ground. Shall we call that evil which was the necessary condition of our intellectual elevation? Evil, doubtless, it seems to us individuals who have suffered and are still suffering through our ignorance; but is such individual suffering or even individual death to be weighed against the psychical elevation of the individual and evolution of the race? Ought not the individual to be willing to suffer thus much vicariously for the race? Is not this seeming evil also a _real_ good?

May we not, then, confidently generalize? May we not say that all physical evil is good in its general effect--that every law of Nature is beneficent in its general operation, and, if sometimes evil in its specific operation, is so only through our ignorance? Partly by survival of the fittest, and partly by intelligence, man, like other animals, brings himself in accord with the laws of Nature, and thus appropriates the good and avoids the evil, and Nature becomes beneficent only. But, also unlike any other animal, man by rational knowledge makes the laws of Nature his servants, and uses them for his own purposes, thus increasing his power and elevating the plane of his life.

4. _Moral Evil._--But there is still another form of evil, the most dreadful of all. This one may be called _the_ evil, in some sense, _the only evil_. It is that of which all other forms are but the shadows cast backward and downward along the course of evolution and on lower stages of existence. This consummation of all evil is _sin_--_moral disease_--more dreadfully contagious and deadly than any organic disease. What shall we say now? Is there any rational explanation of this evil? Is there any possible-reason or excuse for an all-wise, all-powerful Ruler afflicting man alone of all His creatures with this greatest of all evils? In all other cases, the individual and the race sacrifice themselves for a time _physically_ for the sake of final spiritual elevation; but this _is spiritual debasement_. In all other cases, there is a sacrifice in the _course_ in order to attain the _goal_, but this is a missing of the goal itself. Is there any view which mitigates this evil, any philosophic alchemy which can transmute this evil into good? Age after age the human mind has prostrated itself in helpless paralysis before this problem. Most thinkers have been content to say, “Thou hast ordered it so. Thou art good. It must be right.” But many, and among them some of the best minds, have said, “Either God is not all-good, or else not all-wise, or else not all-powerful, or else there is no God at all.” Does evolution shed any light on this dread problem? I believe it does.

We have said that all other evils are but shadows of this one, cast backward and downward on earlier stages of evolution and lower forms of existence. But from the evolution point of view these earlier and lower forms of evil are rather to be regarded as _fore_shadowings of the reality to come. They are but earlier and lower stages of the evolution of the _same thing_--embryonic conditions of the now full-grown evil. If so, then the same law must apply here also, though, as we shall see, with a difference. Here, also, the individual as well as the race finds himself surrounded by what seems an evil environment, against which he must struggle. The spirit of man is inclosed and conditioned by a lower environment, which he must subdue or perish. Here, then, is again a deadly conflict: “a law in the members warring against the law of the spirit, and bringing it into captivity”; a law of selfism warring against the law of love, and bringing it into subjection; solicitations to debasement on the one hand, and solicitations to wrong others on the other. How shall it be overcome? What is the remedy? Again I answer, Knowledge of and conformity to the _laws of the moral world_. But, as in other cases, so in this: this knowledge of and conformity to law, which is the true goal of humanity, will not be attained unless it is forced upon us by necessity and in self-defense--i. e., by evil.

Now suppose, once more, this knowledge and conformity be complete, and the ideal of humanity be attained, and from this final and highest position we look back over the whole ground. Shall that be called evil which from the very nature of a moral being and the laws of evolution was obviously the necessary condition of attaining the goal? Shall we not from this final position call it a good in disguise? Evil, doubtless, it seems to us who suffer and stumble and mayhap fall by the way; but shall the mishap of the individual be weighed as an equivalent against the evolution of the race and the attainment of its goal?

Ah! there is the rub. It is all well enough to talk of sacrificing the _physical_ individual to the race, but not so the _spiritual_. If we believe in the immortality of the human spirit, if we do indeed stand related to God in the manner explained in Chapter IV, then moral evil in the individual has an entirely peculiar and an eternal significance--then the individual human spirit has an infinite worth and can not be sacrificed to the race; for the evolution of the race itself is only in order to the perfecting of individual human souls. What shall we say now? I answer: The sacrifice is not necessary. There is in the realm of morals _alone_ a way of escape--a saving element which redeems the individual without violating the law. Let me explain.

It will, I think, be admitted by all that _innocence_ and _virtue_ are two very different things. Innocence is a _pre-established_, virtue a _self-established_, harmony of spiritual activities. The course of human development, whether individual or racial, is from innocence through more or less discord and conflict to virtue. And virtue completed, regarded as a condition, is holiness, as an activity, is spiritual freedom. Not happiness nor innocence but virtue is the goal of humanity. Happiness will surely come in the train of virtue, but if we seek primarily happiness we miss both. Two things must be borne steadily in mind: virtue is the _goal of humanity_; virtue can not be given, it must be _self-acquired_.

Now we have already seen that in all evil the remedy, which not only cures it but transmutes it into good, is knowledge of law and conformity of conduct thereto--a true science and a successful art--in a word, knowledge of the laws of God and obedience to these laws. In the physical world ignorance of these laws is necessarily fatal, but not so in the moral world. Ignorance here is not necessarily fatal though dangerous. By the very nature of a moral being, the essential thing is not knowledge but _character_ or virtue--the _will_ to know and the _effort_ to obey. In the physical realm, knowledge is the goal; in the moral realm, knowledge is only in order to virtue. Therefore, in the case of the individual struggling with moral evil within and without, the victory is always in his power. If he fails, it is his own fault. His utmost effort in this field must be successful, because the result is not external, but internal and in the realm of moral freedom. The spirit of man is self-acting and in some sense, though not absolutely, self-existing, and can not be ruined except by its own act. In the moral world, where the goal is not knowledge but character, attainment must be in proportion to honest endeavor in the right spirit.

Evil, then, has its roots in the necessary law of evolution. It is a necessary condition of all progress, and pre-eminently so of moral progress. But some will ask, “Why could not man have been made a perfectly pure, innocent, happy being, unplagued by evil and incapable of sin?” I answer: The thing is impossible even to omnipotence, because it is a contradiction in terms. Such a being would also be incapable of virtue, would not be a moral being at all, would not in fact be man. We can not even conceive of a moral being without freedom to choose. We can not even conceive of virtue without successful conflict with solicitations to debasement. But these solicitations are so strong and so often overcome us, that we are prone to regard the solicitations themselves as essential evil instead of our weak surrender to them.

All evolution, all progress, is from lower to higher plane. From a philosophic point of view, things are not good and evil, but only higher and lower. All things are good in their true places, each under each, and all must work together for the good of the ideal man. Each lower forms the basis and underlying condition of the higher; each higher must subordinate the lower to its own higher uses, or else it fails of its true end. The physical world forms the basis and condition of the organic, yet the organism rises to a higher plane only by ceaseless conflict with and adaptation to the physical environment, which therefore seems in some sense evil. The organic world in its turn underlies and conditions and _nourishes_ the rational moral world. As the senses are the necessary feeders of the intellect, so the appetites are the necessary feeders of the moral nature. Yes, even the lowest sensual appetites are the necessary basis and nourishers of our highest moral sentiments. And yet the struggle for mastery of the higher spiritual with the lower animal is often so severe that the latter seems to many as _essential evil_ to be extirpated, instead of a useful _servant_ to be controlled. This view is asceticism. Now the whole view of evil usually held is a kind of asceticism, and therefore, like asceticism, must be only a transition phase of human thought. All that we call evil both in the material and the spiritual world is good, so long as we hold it in subjection as servants to the spirit, and only becomes evil when we succumb. All evil consists in the dominance of the lower over the higher; all good in the rational use of the lower by the higher. Asceticism may, indeed, be the best philosophy for some. If we can not subdue the lower nature, we must try to extirpate it, and thus at any cost set free the higher from humiliating bondage. If we can not practice the higher virtue of _temperance_ in _all_ things, we must even try the lower virtue of _total abstinence_ in _some_ things. If our right eye offends, we must not hesitate to pluck it out; but let us not imagine that one eye is better than two--let us clearly understand that thereby our spiritual nature is sadly maimed, and therefore that the highest virtue, which is spiritual beauty and strength, can not thus be attained. True virtue consists, not in the extirpation of the lower, but in its subjection to the higher. The stronger the lower is, the better, _if only_ it be held in subjection. For the higher is nourished and strengthened by its connection with the more robust lower, and the lower is purified, refined, and glorified by its connection with the diviner higher, and by this mutual action the whole plane of being is elevated. It is only by action and reaction of all parts of our complex nature that true virtue is attained.

FOOTNOTES:

[1] The term _Chorology_, used by Haeckel, nearly covers the ground.

[2] _Ontos-gennao_ (individual-making, or genesis of the individual).

[3] _Taxis, nomos_ (relating to science of arrangement).

[4] This statement is general; it will be modified hereafter.

[5] _Phule-gennao_ (kind-making); genesis of the race.

[6] This formulation of the laws of organic succession was given by me in 1860, before I knew anything of either Darwin’s or Spencer’s evolution. They were my own mode of formulating Agassiz’s views.

[7] Genesis without previous life--spontaneous generation.

[8] Fishes were first introduced in the later Silurian; but became dominant in the Devonian.

[9] Amphibians were introduced in the Carboniferous, but true reptile not until the Permian.

[10] Of course I mean downward in _social function_. Individually the scavenger may be nobler than the statesman.

[11] Cope, “Science,” vol. ii, p. 274, 1883.

[12] Boston Society of Natural History--anniversary memoir, 1880. Also, “American Naturalist,” June, 1882.

[13] “Archives des Sciences,” vol. liv, 1875.

[14] “Nature,” vol. xxxi, p. 4, 1884.

[15] See abstract of Dr. Romanes’s views, “Nature,” vol. xxxiv, pp. 314, 336, 362. Also, discussions of the same by Meldola, Galton, Wallace, etc., in immediately subsequent numbers.

[16] This subject is more fully treated in chapter IX, p. 240 _et seq._

[17] See an article entitled “Genesis of Sex,” “Popular Science Monthly,” 1879, vol. xvi, p. 167.

[18] Mr. Wallace has recently, in his work on “Darwinism,” taken strong ground against this Darwinian factor. He thinks, for example, that sexual vigor is the cause of both the splendor of color and the pertinacity which secures the female. We see little difference in this way of putting it. Our object, however, is not to argue the question of what are true factors, but simply to give the most accepted, and, as it seems to us, also the most probable view.

[19] By _reason_ I mean the faculty of dealing with the phenomena of the _inner world of consciousness and ideas_. Animals live in one world--the outer world of _sense_; man in two--the outer world of sense, like animals, but also in an inner and higher world of _ideas_. All that is characteristic of man comes of this capacity of dealing with the inner world. In default of a better word I call it reason. If any one can suggest a better word, I will gladly adopt it.

[20] While all comparative anatomists agree that the lung is a diverticulum from the œsophagus, like the air-bladder of the gar-fish, some think that it is a _different_ diverticulum, which is seen first in the dipnoi.

[21] Undoubtedly the true principle on which primary groups ought to be made is, _identity of general plan of structure_, or _traceableness of homology throughout_. For these groups are the great primary branches of the tree of life, and classification ought to represent degrees of genetic relationship. This was Agassiz’s principle, although he did not admit the genetic relation. This principle has been, it seems to us, too much neglected by later systematists.

[22] The Amphioxus, the lowest of all vertebrates--if vertebrate it may be called--is an exception to 2 and 3. In this animal the vertebrate type is not yet fully declared.

[23] This is only one example under a general law which it may be well to stop a moment to illustrate. A repetition of similar parts performing the same function is always an evidence of low organization, and as we rise in the scale of organization such parts usually become fewer and more efficient. Thus, to give one example, myriapods, as their name indicates, have hundreds of locomotive organs--lower crustaceans perhaps thirty or forty. As we go up, they are reduced to fourteen (tetradecapods), then to ten (decapods), then in spiders to eight, in insects to six, in vertebrates to four, and in man to two. A similar reduction in number, but increase in efficiency, is found in toes, _when they are used for support and locomotion only_. In man we find the normal number of five (1), because his hands are used for grasping and the functions of the fingers are not the same; and (2), because man’s development was almost wholly _brainward_. In other respects his structure is far less specialized than most other mammals. He can not compete with carnivores in strength and ferocity, nor with herbivores in fleetness. In the struggle for life, therefore, there was nothing left for him but increase in intelligence. Probably four is the smallest number of locomotive organs consistent with highest efficiency. In retaining but two legs for locomotion, man has lost in locomotive efficiency, but by the sacrifice he liberates two limbs for higher functions.

[24] “Proceedings of American Academy of Arts and Sciences,” vol. xiv, May, 1878.

[25] Fol., “Archives des Sciences,” vol. xiv, p. 84, 1885; “Science,” vol. vi, p. 92, 1885.

[26] Of course, this is a purely imaginary case. The conditions of development of the eggs of higher animals forbid continuous watching the process. Yet we do observe in different individuals all these stages in mammals as well as other animals.

[27] These baleen plates are not modifications of teeth, as might at first be supposed, but rather of the transverse gum-ridges found on the roof of the mouth of many mammals, and conspicuous in the horse.

[28] “Proceedings of the California Academy of Science,” vol. v, p. 152. 1873.

[29] For fuller discussion of this subject, see “Bulletin of the California Academy of Science,” No. 8, 1887, and “American Journal of Science,” for Dec., 1887.

[30] “Origin of Races of the Dog.” “Annals and Magazine of Natural History,” vol. xvii, p. 295. 1886.

[31] Mr. Galton (“Nature,” August 26, 1886) has used a diagram similar to the above (which I first used in 1879) to illustrate the law of sexual attraction and repugnance.

[32] This subject is more fully discussed by the author in an article entitled “Genesis of Sex,” in “The Popular Science Monthly,” vol. xvi, p. 167, 1879.

[33] For examples of this the reader is referred to Cope, “Bulletin of the National Museum,” No. 1; and to Coues’s “Key to North American Birds,” last edition.

[34] “Monatsbericht d. k. Preuss. Akademie d. Wissenschaft zu Berlin,” for July, 1866.

[35] “Genesis of Tertiary Species of Planorbis at Steinheim.” A. Hyatt, Anniversary Memoir of the Boston Society of Natural History, 1880.

[36] In a letter to the author, dated February 13, 1887, Prof. Cope says: “Such transitions of species are clearly indicated in the _Oreodontidæ_, where such different forms as _O. gracilis_ and _O. Culbertsoni_ are connected by intergradations.”

[37] “American Naturalist,” 1873; “Popular Science Monthly,” June, 1873.

[38] For a fuller development of this subject the reader is referred to an article by the author, entitled “Critical Periods in the History of, and their Relation to, Evolution” (“American Journal of Science,” vol. xiv, p. 99, 1877).

[39] “Reflex Action and Theism,” William James, “Unitarian Review” for November, 1881.

[40] See an article by the author on this subject, “American Journal of Science,” series ii, vol. xxviii, p. 305, 1859, and in “Popular Science Monthly,” vol. iv, p. 156, 1873.

[41] All chemical compounds are dissociated by sufficient heat.

[42] The origin of vital from chemical force in the green leaves of plants can not be doubted; but this does not, of course, explain the mystery of the _first origin of life on the earth_, for one condition of the change _now_ is the _contact of living matter_.

[43] I know it is the fashion to ridicule the use of the terms vitality, vital force, as a remnant of an old superstition; and yet the same men who do so use the terms gravity, electricity, chemical force, etc. Vital force is indeed _correlated_ with other forces of Nature, but is none the less a distinct _form_ of force, far more distinct than any other unless it be the still higher form of psychical, and therefore it better deserves a distinct name than any lower form. Each form of force gives rise to a peculiar group of phenomena, and the study of these to a special department of science. Now, the group of phenomena called vital is more peculiar, more different from other groups than these are from each other, and the science of physiology is a more distinct department than either physics or chemistry, and therefore the form of force, which determines these phenomena, is more distinct and better entitled to a name than any physical or chemical force.

[44] “Princeton Review” for May, 1884.

[45] “Popular Science Monthly,” December, 1873.

[46] For a fuller statement of this antithesis, see an article by the author entitled “Evolution in Relation to Materialism,” “Princeton Review,” for March, 1881.

[47] Johnstone Stoney, “Nature,” vol. xxxi, p. 422.

[48] “Nature,” vol. xxxiv, p. 385. 1886.

[49] So, again, see a book recently published (“Nature,” vol. xliii, p. 460, 1891), entitled “Whence comes Man, from Nature or from God?” The answer is plain. From both--from God through Nature. Evolution is the method of creation.

INDEX

Acceleration, law of, 178.

African fauna explained, 204.

Agassiz, his greatest result, 29, 43; relation to evolution, 32, 37, 43; relation to Darwin, 46; compared with Kepler, 47.

Ages of geological history, 16.

Alpine species explained, 215.

Amphibians, development of, 150.

Analogy and homology, 99.

_Anima_ of animals, 313, 317.

Animal architecture, styles of, 209.

Animal kingdom, primary divisions of, 107.

Animals, relation of man to, 311; spirit embryonic in, 311.

Antiquity of man, religion and, 282; of the earth, religion and, 281.

Aortic arches, proofs of evolution from, 151.

Arthropods, 132.

Artificial production of varieties, 222.

Australia, fauna and flora of, explained, 200; when isolated, 202.

Barriers limit faunal and floral regions, 188.

Beauty, origin of, 269.

Birds’ tails, changes of, 174.

Brain, vertebrate, proofs of evolution from, 162; vertebrate, changes of, in phylogenic series, 168; relation to mind, 327, 338.

Brain-physiology as a basis for materialism, 306.

Branching tree illustrates evolution, 13-15, 18, 110, 250.

Brooks, W. K., on the cause of variations, 262.

Californian coast-islands, fauna and flora of, 211.

Causation, idea of, from within, 342.

Cause, first and second, 354.

Cells, somatic and germ, 93.

Centers of creation, specific, 194.

Cephalization, 171.

Chambers, his views on evolution, 34.

Changes slow at present, 266.

Christ, the, 359; relation of evolution to, 359; as an agent in human progress, 363.

Close-breeding, effects of, 236, 243.

Coast-islands of California, fauna and flora of, 211.

Comparison, method of, 41.

Conflict between religion and science, 280.

Continental faunas and floras, 188.

Continental island life, 208.

Continuity, law of, 53; law of, applied to inorganic forms, 54; to organic forms, 56.

Cope’s law of acceleration, 178.

Creation, special, 30, 69; specific centers of, 194; changes in our notions of, 348; question of mode, 358.

Cross-breeding, law of, 236.

Cross-fertility of artificial varieties, 232.

Cross-sterility, 77, 234.

Cyclical movement, law of, 16, 22.

Darwin, relation to Agassiz, 46; compared with Newton, 48; factors of evolution discovered by, 74; objections to his theory of evolution, 76.

Derivation, origin of inorganic forms by, 54; origin of organic forms by, 56.

Design, idea of, from within, 345; argument from, not destroyed by evolution, 346; changes in our ideas of, 348; in Nature, question of, 357.

Differentiation, law of, 11, 19; law of, in embryonic development, 19; law of, illustrated, 144; of the animal kingdom illustrated, 176.

Disease, necessity of, 367.

Divine energy, forms of, 318.

Divisions of the animal kingdom, 117.

Dogmatism, theological and scientific, 293.

Domestication, changes produced by, 222.

Egg, development of, 3, 19.

Egyptian species unchanged in three thousand years, 265.

Embryology, proofs of evolution from, 148.

Environment, physical, 73.

Evil, problem of, relation of evolution to, 365; physical, necessity of, 366; a condition of progress, 366, 373; organic, necessity of, 367; moral, necessity of, 369.

Evolution, what is, 3, 8; scope of, 3; type of, 3, 8; examples of, 5; popularly limited to the organic kingdom, 7; progressive change in, 9; laws of, 11; illustrated by branching tree, 13-15, 18, 90, 250; misconception of, 14; produced by resident forces, 27; germs of the idea, 32; relation of Agassiz to, 32, 37, 43; Lamarck’s views on, 33; Chambers’s views on, 34; obstacle to, removed, 35; confliction with religion imaginary, 45; how related to gravitation, 49; general evidences of, 53; artificial, 60; observed, 62; certainty of, 65; special proofs of, 67; factors of, 73, 81; human contrasted with organic, 88; monotypal and polytypal, 85; proofs of, from the vertebrate skeleton, 111; from the articulate skeleton, 132; from embryology, 148; from development of amphibians, 150; from aortic arches, 151; from vertebrate brain, 162; from rudimentary organs, 179; from geographical distribution of organisms, 183; explains geographical diversity, 195; objection to this view, 217; answer, 219; proofs of, from artificial modifications, 222; factors of, operative in domestication, 228; paroxysmal, 257; material, nearly completed, 267; thoroughly established, 275; relation to religion, 276, 282; relation to materialism, 284; necessitates great change in religious thought, 295; of forces, 315; relation to revelation, 331; pantheistic objection answered, 335; relation to problem of evil, 365.

Experimental method largely fails on plane of life, 40.

Factors of evolution, 73; their grades and order of introduction, 81; Lamarckian, 81; selection, 82-85; Darwinian, 83; rational, 86.

Faculties, evolution of, 23.

Faunas and floras, geographical, 183; continental, 188; marine, 192; special cases of distinct, 192; of Australia, 200; of Africa, 204; of Madagascar, 205; of continental islands, 208; of the coast-islands of California, 211; of oceanic islands, 213; of lofty mountains, 215.

Fish-tails, changes of, in development, 172; in evolution, 174.

Fishes, age of, 17.

Floras and faunas, geographical, 183.

Force, vital, correlation of, 36; planes of, 314; evolution of, 315; idea of, from within, 342.

Forces, resident, evolution by, 27; of Nature are forms of Divine energy, 317; different planes of, 314.

Fore-limbs, vertebrate, homologies of, 113.

Generation, spontaneous, 15.

Geographical faunas and floras, 183; diversity, theory of, 193; diversity explained by evolution, 195; present diversity determined by Glacial epoch, 198; objection to this view, 217; answer, 219.

Geological record, imperfection of, 252.

Glacial epoch determined distribution of species, 195, 198, 215; changes during, in America, 198; in Europe, 199.

God, relation of, to Nature, 297; immanence of, in Nature, 300; relation of, to man, 326; personality of, 332; necessary belief in, 344; different forms of conception, 351.

Good and the true, relation of, 277.

Grasshopper, external anatomy of, 143.

Gravitation, relation of, to evolution, 49; and religion, 281.

Gyroscope, 288.

Heliocentric theory and religion, 280.

Hind-limbs, vertebrate, homologies of, 121.

Horse, genesis of, 126.

Homologies of vertebrate skeleton, 111; of vertebrate fore-limbs, 113; of vertebrate hind-limbs, 121; of articulate skeleton, 132.

Homology and analogy, 99; only within primary divisions, 108.

Hyatt, A., on Planorbis, 254.

Ideal, relative and absolute, 364.

Idealism, true and false, 301.

Immortality in accord with law, 316.

Individuality, organic, 325; spiritual, 325.

Innocence and virtue compared, 372.

Inorganic forms, law of continuity applied to, 54.

Intermediate forms between artificial varieties, 232.

Islands, continental and oceanic, 207.

Kepler compared with Agassiz, 47.

Lamarck, evolutionary views of, 33, 74.

Law of differentiation, 11, 19; of progress of the whole, 13, 22; of cyclical movement, 16, 22; of continuity, 53; of continuity applied to inorganic forms, 54; to organic forms, 56; of differentiation illustrated, 144; of acceleration, 178; of cross-breeding, 218, 236.

Laws of evolution, 11, 19.

Lepidosiren, 101.

Life, nature of, 35; imperfectly subject to experiment, 40; relation of, to philosophy, 277.

Limbs, vertebrate, homology of, 113.

Links, connecting, 12, 57, 145; connecting, elimination of, 248; connecting, usually absent from geological faunas, 251.

Liquidambar, 218, 220.

Lobster, external anatomy of, 136.

Lungs, formation of, 100.

Madagascan fauna explained, 205.

Mammals, age of, 17.

Man, age of, 18; relation of, to Nature, 304; relation of, to animals, 311; spirit of, in relation to the forces of Nature, 313, 316; relation of God to, 331.

Marsupials, 201.

Materialism, relation of, to evolution, 284; basis for, in brain-physiology, 306; basis for, in evolution, 311.

Methods, scientific, 38.

Migration favors diversification, 77.

Mind, relation of, to brain, 327, 338; _versus_ mechanics in Nature, 340.

Miracles, question of, 356.

Mollusks, age of, 16.

Monotremes, 201.

Mystery, changes in our sense of, 347.

Nature, relation of God to, 297; immanence of God in, 300; relation of man to, 304; has no meaning without spirit, 329; mind _versus_ mechanics in, 340.

Natural and supernatural, 355.

Neo-Darwinism, 93; relation of, to human progress, 97.

Newton compared with Darwin, 48.

Nominalism and realism reconciled, 329.

Obstacle to evolution removed, 35.

Oceanic island life, 213.

Ontogenic series, 9, 40.

Organic forms, views of origin of, 29, 68, 72, 292; law of continuity applied to, 56.

Organs, incipient, 270.

Origin of varieties unexplained, 270.

Pantheism, true and false, 302, 335.

Paroxysmal evolution, 257.

Personality behind Nature, 338.

Personality of God, 337, 341.

Philosophy and life, relations of, 277.

Phylogenic series, 10, 41.

Planorbis of Steinheim, 254.

Primal animals, 145.

Progress of the whole, law of, 13, 22.

Progressive change in evolution, 9.

Providence, question of general and special, 355.

Ranges of organic forms, 186.

Realism and nominalism reconciled, 329.

Record, geological, imperfection of, 252.

Religion, so-called conflict of, with evolution, 45, 280.

Religious thought to be reconstructed, 295.

Reproduction, methods of, 237.

Reptiles, age of, 17.

Revelation, relation of evolution to, 331; not inconsistent with the laws of Nature, 332; nature of, 333.

Reversion of artificial forms, 229.

Romanes, G. J., his idea of physiological selection, 76, 84; the idea applied, 245.

Rudimentary organs, proofs of evolution from, 179; organs in man, 181.

Selection, sexual, 74, 85; natural, 74, 79, 83; physiological, 75, 79, 84; natural, compared with artificial, 225; physiological, applied, 245.

Self-consciousness the sign of spirit-individuality, 325.

Sequoia, 219, 220.

Sexes, characters of, compared, 262.

Shrimp, external anatomy of, 134.

Sin a condition of moral evolution, 350.

Skeleton, vertebrate, homologies of, 111; articulate, homologies of, 132; articulate, general structure of, 134.

Society, progress of, 25.

Space and time the two fundamental conditions of material existence, 48.

Species, natural, more permanent than artificial varieties, 229; more distinct, 232; cross-sterile, 232.

Spirit embryonic in animals, 311; of man related to _anima_ of animals, 313; to forces of Nature, 313, 316; origin of illustrated, 320-322; Plato’s view, 326; orthodox view, 326; no meaning in Nature without, 329.

Steinheim, Planorbis of, 254.

Supernatural and the natural, 355.

Taxonomic series, 9, 40.

Temperature-regions, 184.

Tread, plantigrade and digitigrade, 123.

True and the good, relation of, 277.

Truth tested by effect on life, 277; not compromise, 291.

Types, generalized, 13.

Use and disuse of organs, 73.

Useless structures, how produced, 76.

Variation depends on sexual reproduction, 238; caused by unfavorable conditions, 264.

Varieties, artificial production of, 222, 235; artificial production of, illustrated, 224; natural and artificial, compared, 228; origin of, unexplained, 270.

“Vestiges of Creation,” 34.

Virtue and innocence compared, 372.

Vital principle, 328.

Voluntary social progress, 26.

Weismann’s views, 93.

Whales, rudimentary organs of, 180.

THE END.

Transcribers’ Notes:

Punctuation, hyphenation, and spelling were made consistent when a predominant preference was found in this book; otherwise they were not changed.

Simple typographical errors were corrected; occasional unbalanced quotation marks retained.

Ambiguous hyphens at the ends of lines were retained.

Subscripts in chemical formulas are represented here as simple numbers, such as H2O and NH3.

Illustrations were printed mid-paragraph but have been moved between paragraphs, usually near to text that references them.

Footnotes have been collected and repositioned just before the Index.

Some in-line paragraph headings are in boldface and some are in italics; this emphasis has been retained.

Index not checked for proper alphabetization or correct page references, but a reference to page 274 was a typographical error and has been changed to 174.

Page 155: Text refers to _c c′_ in Figs. 38-39, but neither figure appears to contain a _c′_ label.