Popular Science Monthly/Volume 7/May 1875/Evolution and the After-Life

From Wikisource
Jump to: navigation, search


FEW persons are able to escape some form of belief in the existence of a soul. Whatever view we may take of its origin, gradations, or development, whether the infinite soul, the human, the animal, and the "soul of things," are each only manifestations in different degrees of the same great principle, or each enlargement and refinement in the ascending series is to be considered a development, or whether nothing is to be dignified as soul except that which is manifested through human forms—whatever views we may have regarding its limitations and destiny—we cannot escape the conviction that there is, in man at least, a distinct entity, a combination of faculties, a blending of sensation, will, and wisdom, which we call soul. Its powers, its modes of action, and its destiny, have been subjects of thought for the thoughtful of all limes. Gradually these thoughts have taken form, and a science of psychology has grown up, engaging in its investigations the efforts of the ablest minds.

It may not be reasonable to suppose that any being, unless it be the Infinite, should perfectly comprehend itself. How far man is from being able to claim such knowledge may be inferred when we consider that, although he has been upon the earth so many thousand years, it is less than three centuries since he began to understand even his physical organization, or comprehend such simple facts in his own physiology as the process of digestion and the circulation of the blood. It is only within the present century that the functions of the nervous system began to be understood, and only within the last few years that its relations to mental activity have been intelligently studied. With so many points in regard to the functions of the material body only recently understood, and even now but imperfectly known, is it strange that our psychical relations should be even less perfectly comprehended?

A recent writer[1] has pointed out the fact that each epoch of intellectual activity and enlargement, as marked by the discovery of new truths in Nature, has been accompanied or directly followed by better modes of investigation and more scientific views in psychology; and not only so, but the methods employed and the results obtained in psychology have had direct relation to the methods and results in physical science. As mathematics and the laws of motion gave us Descartes and Hobbes, scientific medicine or the "science of observation" Locke, the vibratory theory Hartley, and chemistry the elder Mill, so geology and the doctrine of evolution have been potent in influencing the methods and results obtained in psychology by Bain and Herbert Spencer. And as each advance in psychology has had reference to the methods in physical science which have preceded it, so do we find that the doctrine of evolution, which in its general aspect at least has given direction to the scientific thought of the present generation, has also been the doctrine which has thrown most light upon the constitution and action of mind.

It is not the object of this paper to discuss the doctrine of evolution, but simply in the light of that doctrine, as generally understood, to present such facts as science has prepared for us relative to the development of mind, and its manifesting organs in the gradually-ascending series of animal forms.

The organ of all psychical manifestation is the nervous system, and the material of which it is composed is substantially the same, whether in animals of a high or a low organization. It is of two kinds, the gray matter, usually found in nodules or masses of greater or less bulk, called ganglia, and the white matter, usually found in continuous lines, and called nerve-trunks or simply nerves. The ganglia are the centres of power. The trunks are the lines of communication between the ganglia and the different parts of the organism.

Without descending into the debatable ground between the vegetable and animal world (for, strange to say, the boundary-line between the modes of life apparently so different has never yet been established), let us examine an organism as lowly as any possessing a distinct and single nervous system—an ascidian mollusk—which simply means a bag-shaped, soft-bodied animal. It has no head, nor any

PSM V07 D058 Nervous system of ascidian.jpg
Fig. 1.—Nervous System of Ascidian: 1. Mouth; 2. Vent; 3. Ganglion.

organs of sight, hearing, or smell. It consists of a sac, from the lower portion of which proceeds a stomach or digestive tube; these are covered with a muscular envelope, and the whole is inclosed in another envelope or membranous sac called a mantle. These coverings are pierced by two openings—a mouth for admitting water and the nutrient particles which it happens to contain into the inner sac or common reservoir, which also serves as a respiratory organ—and a vent, communicating directly with this sac, and also with the more circuitous digestive tube. A constant stream of water passes through the mouth into this common or respiratory sac, where, after having served its purpose of supplying oxygen to the system, a part is ejected directly through the vent, and the remainder, together with the nutrient particles, passes into the digestive tube, and thus finds its exit.

The nervous system, which is the part most important to our present purpose, is of the most simple kind; it consists of a single ganglion, situated between the two orifices of the body, with each of which it has lines of nerve-communication, and also with the various envelopes which mainly constitute the animal.

All the creature's movements must be carried on by means of this simple nervous arrangement; and, as it is fixed to one spot during its whole life, they must necessarily be of a very limited character; it has, in fact, but one movement—it contracts when touched.[2] Suppose, for instance, some offending substance to have found its way into the common sac, the irritation caused by it is transferred along the communicating nerves to the ganglion; there a "motor impulse" is generated, which again is transferred along the communicating lines from the ganglion to the muscular envelope, causing it to contract and eject the water which it contained, together with the offending substance. This is all the action the creature is capable of, and this it repeats whenever and wherever an irritation is applied. It is the simplest action, so far as we know, requiring a nervous system for its accomplishment, and has received the name of reflex action.

Without following each shade of improvement in the nervous organization of the mollusks, or soft-bodied animals, it may suffice to say that the same general arrangement holds throughout all the lower members of the series, new ganglia being added to meet the needs of a more complex organization until, in the highest members, as, for instance, in snails and the cuttle-fish, important changes are found to have occurred. Instead of the headless and irregular masses which have constituted the bodies up to this point, we now find an animal comparatively symmetrical in form, with a distinct head, and imperfectly-developed organs of special sense. Here, then, occurs the division between the two great classes of animals known as cephalous and acephalous; all the lower species of mollusks, the ascidians, mussels, oysters, and the like, belong to the acephalous or headless class, while with the highest species, snails, the nautilus, and the cuttle-fish, commences the other great class known as cephalous animals, or those having distinct heads.

The advance in the nervous system is correspondingly great; instead of the irregularly-situated ganglia hitherto met with, we find them arranged in pairs, to serve the purposes of the more symmetrical body; but a still more marked and important advance is found in the fact that each organ of special sense (sight, hearing, etc.) is furnished with a separate nerve-centre or ganglion; all of which, being brought together in the head of the animal, constitute what is known as the cephalic ganglia, or sensorium, an incipient brain.

The function of this nervous system is not merely to respond to irritation applied directly to the body, but also to respond to certain stimuli, such as that afforded by sight and hearing, received at the sensorium through the organs of special sense, and thence transferred to the different ganglia. This new stimulus is called sensation, and it is one to which the ganglionic system responds with almost the same alacrity that it does to direct contact.

Leaving now the grand division of mollusks, we ascend to another division in the animal world, namely, the Articulates. It embraces such marine animals as the crab, lobster, and crayfish; and on the land, worms, centipedes, and all the numerous tribes of insects. The characteristic of the whole division is, that the body is made up of rings or segments, joined and moving one upon the other, and hence the name articulates.

The general plan of the nervous organization throughout this large division is that just described, and commencing with cephalous animals. It consists of symmetrically-arranged ganglia—a sensorium, and the necessary communicating nerves.

And what are the actions by which this improved nervous system, characterizing all this large class of animals, manifests itself?

Taking the two extremes in the class of well-characterized articulates, the centipede at the lower, and wasps and bees at the upper, we notice a wide difference in the complexity of the general organization and a difference equally marked in the character of the corresponding actions. In the centipede, the general structure consists of a head furnished with certain organs of special sense, and a body made up of a series of segments—each, with the exception of the last, being a repetition of the others, and each being furnished with a single pair of legs.

PSM V07 D060 Sensorium and connected ganglia of centipede.jpg
Fig. 2.—Sensorium and Connected Ganglia of Centipede.

To preside over these organs of locomotion, the nervous system is distributed as follows: Each segment is supplied with a double ganglion, or nerve-centre, all being arranged in regular order just beneath the alimentary canal, and in the head is placed the sensorium; all the different ganglia are connected by a fine double-nerve filament called the ventral cord, and through this means also all are in communication with the sensorium. So each ganglion is in communication with its own particular pair of locomotive organs, with each of the other ganglia, and with the sensorium.

The chief action of this animal consists in the movement of these organs of locomotion; and this it does in response to direct irritation from without, or in consequence or sensations received at the sensorium through the organs of special sense, and thence transmitted to the several ganglia. So long, then, as this nervous communication remains unbroken, the action of all the segments composing the body is harmonious, and is performed with a direct relation to the guiding influence of the sensorium. This is the normal action of the animal. But suppose, now, that the head, with the sensorium, be removed while the creature is in motion, the legs still perform their office, carrying the body forward in its accustomed manner until it meets an obstruction, when its progress is stopped, though the legs still continue to move. If the body be divided, similar results follow: the forward part moves on under the guidance of the sensorium, avoiding or overcoming obstacles according as sight or other sensations influence; the after-part of the divided body also moves on, but only in obedience to its own ganglionic centres, and without any guidance from, or relation to, the sensorium, or the anterior portion of the body.

Thus we see the ordinary movements of the animal continuing to be repeated with only that part of the nervous system in operation which is capable of producing reflex action. What the entire creature has been accustomed to do, the separate parts continue to do when cut off from the guiding influence of the sensorium. The same holds good even in some of the more highly-organized, members of the articulate series. A remarkable instance is given by Dr. Carpenter, as shown in the mantis, an insect allied to the crickets, which performs its accustomed and very peculiar actions not only when the head is removed, but the segments of the body perform each its accustomed part, and no other, when the body itself is divided. So also a certain kind of water-beetle, after the sensorium is removed, remains motionless so long as it rests upon a dry surface; but, being placed upon the water, its accustomed element and stimulus, performs its accustomed movements of swimming, and with such energy as to strike aside its companions with great violence. These motions, which are repeated, as has been seen, under the influence of the ganglionic system alone, and by the simple process of reflex action, are termed automatic; and when these actions, though often more complex and varied, are repeated in the same automatic manner under the guidance of the sensorium, and under the stimulus derived from sensation, they are called instinctive.

Coming, now, to the higher species of articulates, we find the so-called social insects, and especially bees, furnishing the most wonderful examples of instinctive action; they construct for themselves habitations, some of them involving nice principles of geometry; they store up food for future use, and their whole economy seems, at first glance, to demand the presence and aid of even a rare intelligence; yet, on examination, it is found that no teaching is required, no thought nor memory is brought into use in these remarkable actions, but each insect goes to work without direction and without individual experience, and does at once, without hesitation, the first time as well as ever, that which is in its nature to do. "It acts according to its nervous organization."

How the insect comes by this impulse to do, is one of those seemingly simple questions which, in reality, includes the whole; it is the ever-recurring question regarding each new faculty as it makes its appearance in the series, and demands a few words in reference to the main theories involved. The term instinct is not to be taken, in its popular sense, as referring to all the actions performed by animals in distinction from those performed by man, but must be limited to those automatic actions which are performed without teaching or individual experience. Now this impulse, or instinct, as exemplified in the bee, must, as was formerly supposed, have been directly impressed upon the nervous organization at the creation of the first bee, and transmitted by each succeeding generation, or, as contended by Herbert Spencer and others, the race must have become gradually endowed with it, by a constant repetition of those acts which each individual was stimulated to perform by its surroundings at succeeding times. The former method presupposes a special creation and endowment for each species of animals; a supposition generally rejected by scientific men as presenting insurmountable difficulties, and as not having facts within possible reach to sustain it; for no one has ever known of a special creation. The other method presupposes development in some of its various phases, which, although not without its difficulties, satisfies so many existing conditions, and is constantly helping to solve so many formerly insoluble problems, that scientific men are led to adopt it, provisionally at least, as probably true in its main features, and certainly of great importance as an aid in further investigations.

According to this theory, instinct is the aggregate or accumulated experience of each race of creatures in which it is found—is impressed by repetition upon the nervous organization, and is inherited alike by each individual of a race, causing their actions to be the same, generation after generation, unless changed by necessity from changed surroundings. This is the mode of action characterizing the large class of animals whose highest nervous development is the sensorium. It embraces the cephalous mollusks and the whole division of articulates; and its highest development is reached in insects.

Ascending now another step in the series of animated forms, we find again an advance in the nervous organization suited to the still more complex action and consequent needs of the animal.

Without following out in detail the gradations which take place in passing from the articulate to the vertebrate series, we find in general terms the following changes to have occurred; and, as an example, one of the first and simplest of the series may be taken, namely, the fish. Instead of the ventral cord, with its interrupted series of ganglia, as in the centipede, we find in the fish a spinal cord, existing as a continuous line of ganglionic matter, inclosed in a fibrous sheath of white conducting matter, and the whole protected in the bony canal formed for it by the beautifully-arranged pieces which make up the vertebral column, or back-bone. From this continuous ganglionic centre nerves are given off at different points, as they are needed to supply the different muscles of the body, and especially those of locomotion. We find the sensorium enlarged to preside over the improved organs of special sense, the optic ganglia still being much the more important; and we have two new ganglionic masses added, the cerebrum in front of the optic ganglia, and the cerebellum, placed just behind them. Concerning these, it may be remarked that the latter, although its function has not been so clearly demonstrated as many other portions of the system, shows such marked relations to the complexity and perfection of the movements of which any animal is capable, as to render it nearly certain that its use is to regulate and coordinate muscular action; while the former, as marking a grand advance in the psychic endowments of living creatures, constitutes the most important addition to the nervous system hitherto found.[3]

PSM V07 D063 Brain of fish.jpg
Fig. 3.—Brain of Fish: 1. Olfactory Ganglia; 2. Cerebral Ganglia; 3. Optic Ganglia; 4. Cerebellum; 5. Spinal Cord.

Here, for the first time, inclosed in its bony covering, we have an <organ possessing, even in a rudimentary form, the principal parts of a complete brain. Of these parts the cerebrum, which is found as merely rudimentary in the fish, now takes the precedence in interest and importance—from fishes to reptiles, from reptiles to birds, from birds to mammalians, and all through the mammalian tribes, from the imperfect marsupial upward to the anthropoid apes and man, we find in the main, an unbroken line of increase in cerebral development, and corresponding increase in intelligence.

Then, again, it is of interest to inquire the manner in which this new faculty, intelligence, makes its appearance along with the improved nervous organization, and how it differs from the instinct of the classes below.

According to the eminent authority before referred to, as instinct is the aggregate experience of the race, accumulated and impressed upon the nervous system by innumerable repetitions, inherited by each individual of the race and available all at once, so intelligence is the aggregate individual experience and is available only as acquired, though the facility for acquiring it varies according to the nervous organization. Both instinct and intelligence may exist in the same individual, but generally, in proportion as actions governed by intelligence become numerous, those governed by instinct decrease in number and importance. In observing the nervous organization of the centipede as the representative of a dawning instinct and its appropriate manifesting organ, the sensorium, it was found that reflex action, characteristic of acephalous animals, did not cease when the head and its special ganglia appeared, but that a large share of its actions was still purely reflex in character, even those prompted by its small and imperfect sensorium being but little raised above the reflex and into the region of instinctive actions; and that the ganglionic system and reflex action were continued all through the higher mollusks and the whole series of articulates, only diminishing in importance as the sensorium and instinctive action increased. So in the commencing vertebrate series, we find the nervous organization of the preceding races continued—that for reflex action being represented in the spinal cord, and that for instinctive action being continued in the sensorium; not only so, but in proportion as the cerebrum remains small and undeveloped, and the sensorium predominates, do instinctive actions remain in the ascendant both in number and importance. This is found to be true in all the lower orders of vertebrates—fishes and reptiles; and even in the lower mammalians, although the cerebrum may outweigh the other portions of the brain, still a very important part of the actions manifested is instinctive. As an example of this in birds.

PSM V07 D064 Brain of pigeon.jpg
Fig. 4.-Brain of Pigeon: 1. Cerebrum; 2. Optic Ganglia; 3. Cerebellum; 4. Optic Nerve; 5. Spinal Cord.

may be mentioned the chick, which breaks its prison of shell with its beak and immediately runs about, sees and picks up its particle of food with unerring certainty without teaching or experience, hears and answers the call of the mother-bird, and scrambles toward her for protection although it may never have seen her. Birds also possess in a remarkable degree the impulse, akin to that of insects, for preparing elaborate habitations; but unlike the insect races they add a certain degree of intelligence to their work, varying it in form and material according to locality and surroundings, and even finishing for their own use that which others had left incomplete and abandoned. In proportion as instinct ceases to predominate, the work becomes less uniform; and so it may be observed in general, that in proportion as the habits of a given race are fixed and automatic, does each individual conform in its action to that prearranged method, and we know what each individual under given circumstances will do; but, as Intelligence increases and a larger range of actions is performed, this power to predict how any individual will act is gradually lost.

Advancing step by step upward in the mammalian series, certain changes in the development of the cerebrum occur, accompanied in each instance by the introduction of new faculties or the improvement of old ones. Throughout the lower orders—fishes, reptiles, and birds—the cerebrum, though constantly increasing in relative size from mere nodules of gray matter less in size than the optic ganglia, up to masses of much greater bulk than the sensorium, still retains the same general appearance—two smooth oval bodies, one on each side of the median line, and gradually approaching each other as they enlarge until they meet, then extending forward and backward so as more and more to cover in and hide the sensorium. These represent the hemispheres; and this is the condition of brain which is found in the lower mammalians. Associated with this cerebral development we find u psychical condition not very far advanced beyond that already considered as pertaining to birds; namely, action partly prompted by instinct, and partly controlled by intelligence, as especially seen in the rodentla, or gnawing animals. The perfection of instinct and want

PSM V07 D065 Brain of rabbit.jpg
Fig. 5.—Brain of Rabbit (Rodent): 1. Olfactory Ganglia; 3. Cerebral Hemispheres; 3. Cerebellum; 4. Spinal Cord. Other parts of Sensorium covered by Cerebrum.

of reasoning power in regard to certain actions are well illustrated in an example quoted by Dr. Carpenter. It is that of a beaver which a gentleman kept in his house, and who, notwithstanding his unfavorable surroundings, would exercise his instinct for dam-building on all occasions; for materials he appropriated brooms, warming-pan, walking-sticks, baskets, boots, and books, or in fact any thing portable within his reach, arranging them in the most approved style of beaver architecture, although he had never witnessed the process in others. He exercised the same skill, also, in preparing himself a dwelling. The absurdity of the whole process from a reasoning point of view was obvious from the fact that he had no access to water, and was already comfortably housed. He was simply working out what was impressed upon his nervous organization by countless generations of dam-builders before him, independent of circumstances or uses. In this class, however, are commenced two grand improvements in the cerebral development: first, the uniting of the two parts constituting the hemispheres by a broad band of fibres, known as the "great transverse commissure," indications of which appear in the rodents; and, second, "indications of a 'middle lobe' marked off from the anterior by the fissure of Sylvius." To these soon are added the "convolutions" or corrugation of the outer or cortical layer of the hemispheres, so as to secure more surface of active nerve-material without additional bulk; and lastly, in the apes, appears the commencement of the third or "posterior lobe."

In the human brain no addition of parts is presented, but only improvements in those parts found in animals next below. One of these improvements is the more perfect communication established between the diffrent parts composing the brain; the great "transverse commissure" connecting the two hemispheres is much better developed than in any of the preceding races, also the fibres connecting the cerebrum with the sensorium upon which it lies; the "convolutions," only indicated by slight depressions even in monkeys and apes, become conspicuous in the human brain, giving it the appearance of being gathered up in deep folds; and the "posterior lobe," which, as we have seen, first makes its appearance in the highest apes, is much increased in man, even in the uncultivated tribes, as is also the comparative bulk of the whole cerebrum.

PSM V07 D066 Human brain.jpg
Fig. 6.—Human Brain: 1. Cerebrum: 2. Cerebellum: 3. Spinal Cord. Sensorium covered by Cerebrum; a, b, c, Anterior, Middle, and Posterior Lobes of the Cerebrum.

These various improvements, gradually succeeding each other, are accompanied by psychical developments equally marked; gradually the strong instincts and limited perception of surroundings, which tend to make all the individuals of a class alike in physical and pyschical endowments, give place to more complex sensations, gathered from a wider range of surroundings. The cerebrum begins to take cognizance of these sensations, and to give its approval, before they are translated into actions; memory dawns—hatred, fear, anger, and revenge, are born; a certain adapting of means to ends gives evidence of commencing reason; affection, love of approbation, joy, and sorrow, all these appearing in the races most associated with man, proclaim the presence of faculties and endowments far above the plane of mere instinct, and bordering close upon attributes usually applied to soul alone, and in its more dignified estates.

Examples of such endowments in the brute races can hardly have escaped the notice of any intelligent observer. In the faithful dog, who at a word from his master collects the stray flock in the stormy Highlands, or brings in the helpless and perishing traveler from the snowy Alps; who shields his child playmate from the passing danger, or rescues him from threatening death; who, himself hungry, guards food for others; who with quick perception notes and shares his master's varying moods, and who metes out justice for the weak against the strong, we behold in humble guise a dawning soul, with which no truly noble soul need wish to ignore kinship.

To note all the improvements in the physical organ of mind in man, and point out the vast psychical advances which are found in him, compared with the best of the races beneath him, would far exceed our limits. We may, however, notice here that, as in his nervous organization, no distinctly new parts are discoverable, but only general growth and development, and especially vast increase in the size and working capacity of the cerebrum, together with improved lines of communication between the different parts of the brain, so in the psychical manifestations which this enlarged and better-developed brain exhibits, no faculties are discovered beyond what these various developments in structure render possible. Does man possess intelligence? It is found also in the lower tribes. Memory? Many races of animals possess it. Reason? No definition of it can be formed, consistent with its exercise in man, which can debar it from some feeble exercise in his more lowly companions. Up to the point which their organization permits, they possess and exercise faculties akin to those of man. But it is in the degree and perfection to which these faculties attain that the superiority of man is evident; and here the difference is vast indeed. The intellectual superiority of an ordinary man over the most sagacious animal, which nevertheless can scarcely be taught the simplest relation of numbers, is too vast to be readily comprehended; but so is the difference immense between the reasoning powers of an infant and a man, or a Hottentot and a Cuvier or Laplace. If a dog cannot be taught simple arithmetic, neither can a Hottentot be taught optics nor analytical geometry, nor be made to take in the idea of "quantitive reasoning" nor "correlation of forces." The dog is capable of improvement, limited only by his organization; the Hottentot only by his, and the child, of a large-brained and cultivated ancestry by his. The difference in these possibilities, however, can only be comprehended upon reflection. The most intelligent animal, or even the savage man, bears relations to no surroundings beyond the mere seeming of things upon the few acres or miles traversed by his race or tribe; the sun and moon are only what they appear; they rise just beyond the mountain, and they go down in the forest. The thunder and the tempest are incomprehensible, or are the voice and breathings of an angry God. The philosopher, or man of science, on the contrary, holds converse with all objects, animate and inanimate; all peoples and their works, both present and past, upon the surface of the earth. He explores its depths, and calls up before him the generations which peopled it ages on ages past. The microscope brings before him the world of the infinitely small, and the telescope reveals the worlds of space. With the spectroscope he questions the stars, and they give intelligible reply. Such, and a thousand-fold more, are his surroundings; and it is to express his relations to these, to the complex impressions and sensations to which they give rise, and the reflections and aspirations which they inspire, that the brain of the philosopher must be adequate.

We have thus noticed the more prominent structural changes as they occur in the nervous system, from its simplest form to its highest development, and also the corresponding psychical manifestations, which each advance in structure rendered possible. We have seen the lowly creature, endowed with its single nerve-centre, and its radiating nerve-filaments, expressing all its relations to the outer world by simple reflex action; and, if, as we should expect, the order of appearance in Nature corresponded with the order of development, for untold ages all over the silent, ocean-clothed earth, no higher form of life, and no higher expression of soul, was present. Gradually, by many a minute addition, in response to improved surroundings and new requirements, new organs appeared, until at length there existed a creature of definite form, with organs of sight and hearing, as well as touch and locomotion. The old ganglionic nerve-system, with its simple reflex movements, was still retained; but, to express the many new relations to the outer world which its gradually-acquired organs made possible, additional nerve-centres were required, and the sensorium assumed form and use. The series of actions performed through its promptings we call instinctive. Then for unknown ages sense impressions, stimulating to instinctive action, were the highest expressions of soul upon the slowly-emerging earth.

But, again, improved surroundings—the dry earth, with forest, field, and flower, the brighter sunlight and the purer air, demanded new organs to appropriate and new senses to enjoy; and a race appeared with improved organs of sense to receive impressions from this better outer world, improved modes of action, and above all in place, and superior to all in function, an organ of intelligence was added. The old methods of soul-manifestation continue; both reflex and instinctive action find their appropriate place in the higher organization; but they are not sufficient for the numerous and complex relations which now existed between the creature and the outer world; then the cerebro-spinal system comes into being, consciousness becomes perfected, intelligence established, and reason dawns.

Again, ages elapsed in gradual changes, until at length man, the crowning excellence, appeared—an upright form, a powerful brain, a soul capable of tracing causes, and even seeking to find out the First Cause. He was the first to place an ideal—his highest conception of good—before himself, and say, "Now for this will I strive;" the first of all the long line of sentient beings to aspire after a higher life; the first to say within himself, "I shall die," or ask, with ever-increasing interest, "Shall I live again?"

And what is the relation of science, especially as represented by the doctrine of evolution, to this aspiration after a future life? The objections raised against the doctrine by the religious world—the uninstructed part, at least—are that it banishes Deity and tends to materialism.

If by banishing Deity is meant that conception of him which particular sects or peoples have obtained, and are each desirous that all the world should have, the objection may or may not have foundation; but, if it is meant that the doctrine shuts out a great first and adequate cause for all the grand and orderly series of events and existences in Nature, nothing could be further from the truth. The desire to seek for causes is one of the developments of the human mind, increasing in direct ratio with the increase of intelligence. Brute intelligence exhibits no such desire. The savage mind does not rise far into that sphere of intelligence which demands causes; it is only as a higher reasoning power dawns that analysis commences, and causes are sought after; and the higher the intelligence and stronger the power of reason, the more imperative the demand for causes, and the more perfect the comprehension of them.

What is true of causes in general is true in a still greater degree of remote causes, and of a first cause; and hence that which we should expect to occur is found to be the fact, namely, that the scientific men of the present time, the well-developed and well-cultivated minds in all departments of learning, but especially in physical science, are the ones most fully established in an intelligent belief in an adequate first cause. The time is past in which the feeblest artificial works found upon the surface of a single planet, even to the flint-hewn weapons of an unknown race, must have assigned for them a competent originator, and yet man himself, with his complex organization, the long line of organisms of which he is chief, the planet on which he dwells, the system to which it belongs, and the whole vast system of systems sweeping in unimagined circles through space, all be supposed to exist, and have no architect and no supporter. Such is not the deduction of science, and such is not the conclusion at which the most skilled interpreters of Nature have arrived. In examining any artificial work, it is an instinct with man, and his reason approves, to assign for it a conscious and intelligent cause; and he knows that the cause exists in mind, for without mind nothing could be planned or originated. Not only so, but in every instance we judge of the character of the originating mind by the product. A great and noble work is not originated by a feeble and undeveloped mind, nor a crude and imperfect work by a large and well-disciplined one.

We judge similarly in regard to every work, from the crude utensils of the "cave-dwellers" to the mighty products of a Michael Angelo, a Shakespeare, or a Laplace. So, in judging of works compared with which the mightiest works of man are as mole-hills, whose beauty it is the highest exercise of his genius feebly to copy and represent, whose method and arrangement it is the life-work of the most exalted intellects to discover, and whose extent, either in time or space, he still gropes to find the unit of, we assign for cause a corresponding soul; and he who comprehends best the work is capable of understanding best the architect.

The gods of sects and specialties may perhaps be failing of their accustomed reverence, but, in the mean time, there is dawning on the world, with a softer and serener light, the conception, imperfect though it still may be, of a conscious, originating, all-pervading, active soul—the "Over-Soul," the Cause, the Deity; unrevealed through human form or speech, but filling and inspiring every living soul in the wide universe according to its measure: whose temple is Nature, and whose worship is aspiration.

Science, then, so far from excluding God from the universe, demands him as an ever-active power; but, as man can only know him through his works, and as the universe is yet comparatively unknown to him even in his highest condition, and must remain so while he is confined to earth, it follows that our knowledge, and even our conceptions of him, must be limited and imperfect, and our appreciation of him correspondingly so.

Is there, then, reason, in harmony with science, to expect an existence under more favorable circumstances for a knowledge and appreciation of this originating soul whom science itself demands?

As interpreted by the doctrine of evolution, we find man, as he now exists, with his physical organization and advanced psychical being, the product of a long series of developments. lie has arrived, however, only at a certain point in the ascending series; from that point he easily reviews the whole long line beneath him from the very beginnings of organization and life, and admires its grand and orderly procession; but, reaching out forward, he seems to find nothing within the scope of his physical senses. He sees, however, that the series is not ended, for reason assures him that even for the material universe there is, somewhere beyond, an architect whose skill and wisdom he is only commencing to appreciate, but still more, when he beholds the gradual unfolding of the world of soul, with its instinct, consciousness, intelligence, memory, reason, feeling, and aspiration, and considers the possibilities which still may lie enfolded there, is he lost in admiration and wonder at the great centre-soul, the author of all these attributes. And what is to span over the abyss, or even roach out toward this ineffable soul? Is he himself to cease when the material organization wears out?—and consciousness, memory, reason, and, higher, nobler and purer than all, heaven-born aspiration, the crowning development of countless ages, do they all go out in darkness just at the dawning? or, rather, do not the organization of elements and their development into life and movement, the gradual dawning of instinct and reason, and, lastly, of an aspiring soul, give promise of further development under more favoring circumstances for approaching, knowing, and appreciating the great central, causal, all-pervading soul?

For scientific proof of this after-life and future development, the whole world is looking, nor is there any thing unreasonable in the expectation. The orderly steps in the series of development suddenly end with the birth of a soul capable of inquiring after its Author, and aspiring to a continuous life. Is it, then, the end of the series, or must there not be further steps approximating toward the central soul, and observers have not searched aright, or means of observation been imperfect or misused? As, in our solar system, the "law of distances," found to exist among the planets, caused astronomers to look for another body in the huge space between Jupiter and Mars, who were rewarded by the discovery of the Asteroids; or as perturbations in the motions of Uranus caused them to look for a planet beyond its orbit, and Neptune was found; so, with equal reason, may psychologists infer the existence of a whole series of superior beings reaching onward toward the Infinite; and who shall deny the possibility of their discovery? The development of man is constantly leading on to the appreciation of more and more subtile elements and effects; the laws which govern the atmosphere—light, sound, and magnetism—which could not have been understood in the infancy of the race, are being unfolded; colors which our remote ancestors could not perceive, are being differentiated; and sounds, which to them were unmeaning noises, or were not discerned at all, to our more refined and better-developed senses convey impressions of pitch and harmony. Such advance in the development of the ordinary senses, not to discuss the possibilities of an internal and still higher sense, gives promise of future known relations to that which is subtile in the domains of biology and psychology, beyond that which has hitherto been attained.

In this view Science need not despair, and has no right to give over its efforts nor neglect its opportunities to obtain appreciable evidence, however slight it may at first appear, of a future life—one which the doctrine of evolution demands should be a higher development, one of greater possibilities than this. The aspiration after such a life is as much a development of the soul as is intelligence, or reason, or a desire to know causes, and there is the same reason to believe that it has its foundation in a corresponding reality.

And, great as have been the triumphs of science hitherto—great as has been the light which the grand thought of evolution has thrown upon the whole plan and system of the universe—nothing hitherto accomplished could compare in grandeur with the physical demonstration of a higher mode of life and action than that attainable with our present organization and present limitations; a demonstration which would enable man to lie down to sleep with the knowledge that he will awaken to an enlarged and ever-enlarging, conscious, future life.

  1. "The Development of Psychology," Westminster Review, and Popular Science Monthly, July and August, 1874.
  2. For many of the facts and illustrations here stated, see "Mental Physiology," by Dr. Carpenter, chapter ii.
  3. As expressed by Mr. Fiske, in his "Cosmic Philosophy," the cerebellum presides over space relations, while the cerebrum presides over time relations.