A creeping Amœba, or unicellular Protist that changes its form continually; with cell-nucleus in the middle, within which is the nucleolus. After Haeckel.
Gastrula of a Gasteropoda (Gastrœada)
After Haeckel.
A. Ectoderm. B. Endoderm. C. Mouth. D. Gastric cavity.
EVOLUTION OF MIND.
It seems hardly credible that there should exist people who profess to accept the Darwinian theory of development of species in all its fulness, and yet reject the idea of the human mind having been evolved by slow stages from the primitive sense-organ of our lowliest ancestors, the Protista. Such inconsistency seems almost puerile, and, were it not for the fact that the admission of this truth would be the final blow at the various faiths of the world, we should not be called upon to-day to defend a position so utterly impregnable as that assumed by Haeckel and others in regard to the evolution of the human mind. When education has advanced further there will, we must hope, be less of this shutting of the eyes to obvious truths for the mere sake of propping up for a little while longer the belief in a batch of fairy tales and preposterous legends. As we look around us upon the wonderful objects of nature we see everywhere animation and law; the heavens above are full of life—suns, planets, moons, and other celestial bodies incessantly moving to and fro, all bound in their courses by the immutable laws of nature; the vast ocean, teeming with myriads of living beings, is incessantly rolling and roaring like some great monster, but never exceeds the limits which nature has assigned to its action; and the whole face of the earth presents a constant scene of activity of some kind or other—volcanoes discharging their molten fluid, huge glaciers grinding along the ground, monster rivers rushing forward with incessant roar, and the vegetable and animal kingdoms increasing and multiplying at a marvellous pace. All this is life—in fact, everything we see around us, of whatever form or shape, is life of some sort. The very ground upon which we stand is full of life, each particle of dust being held to its fellow particles by mutual attraction; and there is not a single atom of the earth’s substance or of the whole universe that we can say is minus this property of life or activity; nothing in the universe that we know of ever remains for one moment in a state of rest; everything is constantly moving, and every particle of the whole contributes its own share to the general activity which we term motion or life. The whole universe is a huge manifestation of phenomena, which make up the sum-total of life or activity. The sun rotating on its axis is one form of life; the moon silently wandering round our planet is another form of life; the trees and animals growing and multiplying on the land are other forms; and every lump of ore taken out of the ground and every paving stone in our streets are other forms of life. Every particle of every substance whatever is in a state of continual motion, and therefore full of life. In fact, it is this very motion or life that sustains matter; for matter could not exist—that is, its particles could not hold together, and thus form substance—without the life, motion, activity, or whatever we like to term the property which operates upon them and produces mutual cohesion.
Life has always, therefore, been active in matter, and always will be, for life or motion cannot be separated from matter; and, just as matter has passed from a condition of homogeneity to one of heterogeneity, so has life done likewise. Life possesses infinite potentiality, and manifests itself in an infinite variety of ways by means of different combinations, which it brings about in the molecular atoms of universal matter. It acts, for instance, upon a planet by causing its particles to hold together in one mass apart from other bodies of a similar or dissimilar character; it also acts upon what we unscientifically call inanimate nature by causing its particles to hold together, forming in one case a stone, in another a metal, etc.; and it acts upon what we term animated nature by causing its molecules to combine and procreate. This power of attraction and cohesion of particles of universal matter is life, and it depends entirely upon what particular combination of the molecular atoms of universal matter takes place whether a sun, a moon, a planet, a stone, a crystal, a sponge, a tree, or a man be the result. This much is certain, however, that not one of these bodies can ever be produced except by an evolutionary process subject to the universal and unchangeable law which fixes the sequence.
Animal life, as distinct from all other life, is a comparatively late development or manifestation in the sequence of universal phenomena. This world on which we live had existed as a compact body for millions of ages before life assumed the character of animal life; and so gradual was the process of evolution from the primal condition of homogeneity, through all the manifold stages of life, until the condition of animal life was reached, that it is impossible to fix a particular moment when such life became manifest. So it is with every stage of the evolutionary process; there are no starting-places for particular species, the whole being one continuous unfolding of phenomena, without arrest of any kind.
It is equally impossible to fix a particular point or moment for the manifestation of the crystal life as it is for that of the animal or the vegetable life. All are but gradual unfoldings of the universal potentiality. Crystal life is the highest development of what is popularly but erroneously termed inanimate nature, and differs not one iota from Moneron life, which is the lowest form of animal life, in its constituent elements, the only difference between the two being in the mode of combination of the elementary particles composing each. The crystal elements combine in such proportions as to cause the mass to hold together like other solid bodies, its bulk being increased by the deposition of fresh particles upon its outer surface; while the Moneron elements combine in such a manner as to render the body soft and yielding, so that it can absorb nutriment from without to within and multiply by fission. The elements of both are identically the same: the manner of combination causes the differences between them. Many learned men declare that, if this were true, we ought to be able to take the five elements—viz., Oxygen, Hydrogen, Nitrogen, Carbon, and Sulphur—in the necessary proportions, and, by uniting them, form animal life. This, they say, has been attempted, and the result has been failure; therefore, animal life could not have been generated in that manner, but must have been specially created at some particular moment. This argument is absurdly unsound. These persons might just as well say that, to substantiate the assertion that crystals are formed of a combination of elementary molecules, we ought to be able to take the necessary quantity of these elements, and, by uniting them together, form a crystal; and that, if this cannot be done, then crystals also require a special creation. The same argument for a special creation will apply to every species of the animal, vegetable, and mineral kingdoms. Protoplasm is the lowest form of animal life, differing from the highest form of mineral life only in the mode of combination of its elementary particles; but this difference causes the manifestation of fresh phenomena, in this case as in every other modification of a previous state of nature, which gives it the appearance of possessing a property that had not been possessed by any substance previously, whereas, in truth, the apparently new property is but a further development of that previously possessed by inorganic bodies. In short, the power of absorption possessed by the Moneron is simply one of the many manifestations of that universal life or energy that is inherent in all matter, and has been so from all time; but it is a comparatively late development, occurring at a particular period in the world’s history, when the conditions necessary for such a development were present. Before this period no such combination of molecular atoms took place with the same result, simply because the necessary conditions of development were absent. In the same manner precisely there was a prior period when no such substance as a crystal existed, the conditions requisite for the peculiar combination of molecular atoms to result in the formation of a crystal having been absent.