So soon as one of the higher animals comes into the world a number of simple vital activities are already in progress or are at once initiated. Some of these are what are termed "automatic actions," or actions which take their origin within the organ which manifests the activity; such are the heart-beat and the rhythmical contractions of the intestines by which the food is pushed onwards through the alimentary canal. Some are reflex, or responsive, actions, taking origin from a stimulus coming from without; such are the contraction of the pupil of the eye under bright light, the pouring forth of the secretions on the presence of food in the alimentary canal, taking the breast, sneezing, and so forth. Some are partly automatic and partly reflex; such is the rhythm of respiration.

In addition to these vital activities, there is a vast body of more complex activities, for the performance of which the animal brings with it innate capacities. Some of these, which we term "instinctive," are performed at once and without any individual training, as when a chicken steps out into the world, runs about, and picks up food without learning or practice. Others, which we term "habitual," are more or less rapidly learnt, and are then performed without forethought or attention. The store of innate capacity is often very large; and a multitude of activities are ere long performed with ease and certainty so soon as the animal has learnt to use the organization it thus inherits. And lastly, built upon this as a basis, by recombining of old activities in new modes, and by special application of the activities to special circumstances, we have the activities which we term "intelligent;" and here again the activities are sometimes divided into two classes, answering respectively to the reflex and the automatic, but on a higher plane, according as they are responsive to stimuli coming more or less directly from without, or spontaneous and taking their origin from within. But it is probably rather the remoteness and indirectness of the responsive element than its absence that characterizes these spontaneous activities.

Another classification of activities is into voluntary and involuntary. Voluntary actions are consciously performed for the attainment of some more or less definite end or object. Involuntary actions, though they may be accompanied by consciousness, and though they may be apparently purposive, are performed without intention. Notwithstanding the conscious element, they may, perhaps, be regarded as rather physiological than psychological. The simple vital activities belong to this class. But some are much more complex. If, when I am watching the cobra at the Zoo, it suddenly strikes at the glass near my face, I involuntarily start back. The action is apparently purposive, that is to say, an observer of the action would perceive that it was performed for a definite end, the removal from danger; it is also accompanied by consciousness; but it is unintentional, no representation of the end to be gained or the action to be performed being at the moment of action framed by the mind. On the other hand, if I perform a voluntary act, such as selecting and lighting a cigar, there is first a desire or motive directed to a certain end in view, involving an ill-defined representation of the means by which that end may be achieved; and this is followed by the fulfilment of the desire through the application of the means to the performance of the act.

In the carrying out of voluntary activities, then, both perception and emotional appetence are involved. There are construction and reconstruction, memory and anticipation, and interwoven therewith the motive elements of appetence or aversion. It is emotion that gives force and power to the motive. And this must be regarded as the dynamic element in voluntary activity, while intelligence is the directive element. Feeling is the horse in the carriage of life, and Intelligence the coachman.

Let us here note that, in speaking of the activities of animals and the motives by which they are prompted, we are forced, if we would avoid pedantry, to leap backwards and forwards across the chasm which separates the mental from the physical. Motives, as we know them, are mental phenomena; the activities, as we see them, are physical phenomena. The two sets of phenomena belong to distinct phenomenal categories. In ordinary speech, when we pass and repass from motives to actions, and from actions to the feelings they may give rise to, we are apt to be forgetful of the depth of the chasm we so lightly leap. And this is no doubt because the chasm, though so infinitely deep, is so infinitely narrow. There are, however, no physical analogies by which we can explain the connection between the physical and the mental, between body and mind. The so-called connection is, in reality, as I believe, identity. Viewed from without, we have a series of physical and physiological phenomena; felt from within, we have a series of mental and psychological phenomena. It is the same series viewed from different aspects. This is no explanation; it is merely a way, and, as I believe, the correct way, of stating the facts. Why certain physiological phenomena should have a totally different aspect to the organism in which they occur from that which they offer to one who watches them from without, is a question which I hold to be insoluble. All we have to remember, however, is that, in passing from the mental to the physical, we are changing our point of view. The series may be set down thus—

The physical stimulus and the resulting activities are occurrences in the external world, and more or less lie open to our view. But the intervening physical and physiological neural processes are hidden from us. As occurring in ourselves, however, the mental states which are the inner aspects of these neural processes stand out clearly in the light of consciousness. When, therefore, we are watching the life-activities of others, we naturally fill in between the physical stimulus and the activities, not the neural processes of which we are so ignorant, but mental states analogous to those of which we are conscious under similar conditions. Thus we leap from the physical to the mental, and back again to the physical, as represented by the diagonal lines in the above scheme. And there can be no objection to our doing so if we bear in mind that we are thus changing our point of view.

The human organism, then—for at present we may regard the matter from man's own position—is a wonderfully delicate piece of organization, with mental (inner) and physical (outer) aspects. It is in a condition of the most delicate equipoise. Under the influence of a perception associated with an appetence, or of a conception accompanied by a desire, it is thrown into a state of unstable equilibrium; the performance of the action which leads to the fulfilment or satisfaction of the appetence or the desire restores the stability of the system. The instability is caused by the conjoint action of an attraction towards some state represented as desirable, and a repulsion from the existing state which is relatively undesirable. In some cases the attraction, and in others the repulsion, is predominant. When we are in an uncomfortable position, the discomfort is predominant, and we seek relief by changing our attitude. When the bright sunshine tempts us to go out for a walk, the attraction is predominant. But if the uncomfortable attitude is enforced and prolonged, we have a mental representation of the relief we long for; and this is attractive. And if we have work which keeps us indoors, the irksome restraint brings with it an aversion to our present lot. Inseparably associated with the appetence or aversion there is a representation of the activity which constitutes the fulfilment of the emotion. On the physiological side this is probably an incipient excitation of the muscles or other organs concerned in the requisite actions. The miser's fingers itch to clutch the gold, the possession of which he desires. Our muscles twitch as we long to join in the race or the active contention of a game of football. Our horse grows restive as the hunt goes by. Our dog can scarce restrain himself from racing after the rabbits in the park. Under the influence of emotion, then, the body is prepared for activity, the organs and muscles are beginning to be innervated, and, if the appetence or desire be sufficiently strong, the appropriate actions are initiated, and the organism tends to pass from the state of unstable equilibrium arising out of a pressing need to the stable condition of satisfied appetence. The function of the will in this process we shall have briefly to consider presently.

Let us here notice, with regard to the activities, what we have before seen with regard to the process of perceptual construction. We there noticed that, at the bidding of a relatively simple suggestion, a complex object may be constructed by the mind. This presupposes a highly complex mental organization ready to be set in motion by the appropriate stimulus. The organization has been established by association and through evolution in the individual and his ancestors. It is the same with the activities. They, too, are the outcomes of associations and experiences established and registered during generations of ancestral predecessors. At the bidding of the appropriate stimulus arousing impulse or appetence, a train of activities of great intricacy may be set agoing with remarkable accuracy and precision. It is true that a certain amount of individual education is required to draw out and establish the latent powers of the body, as also of the mind; but the ability is inborn, and only requires to be cultivated. Every one of us inherits an organization rendering him capable of performing a vast amount of mental construction and a great number of bodily activities. All he has to do is to learn how to use it and to make himself master of the powers that are given him.

At first, the acquisition of this mastery over the innate powers, even in the performance of comparatively simple muscular adjustments, may require a good deal of attention and practice. But, as time goes on, the frequent repetition of the ordinary activities of everyday life leads to their easier and easier performance. In simple responsive actions the appropriate activity follows readily on the appropriate stimulus. And, ere long, many acts which at first required intelligent attention are performed easily and without consciousness of effort or definite intention. A close association between certain oft-recurring stimuli and the appropriate response in activity is thus established, and the action follows on the stimulus without hesitation or trouble. With fuller experience and further practice in the ordinary avocations of life, the responsive activities link themselves more and more closely in association, become more and more complex, are combined in series and classes of activity of greater length and accuracy, and thus become organized into habits. Under this head fall those activities which we learn with difficulty in childhood, and perform with ease in after-life. At first voluntary and intentional, they have become, or are becoming, through frequency and uniformity of performance, more or less involuntary and unintentional.

"The work of the world is," we are told, "for the most part done by people of whom nobody ever hears. The political machine and the social machine are under the ostensible control of personages who are well to the front; but these brilliant beings would be sorely perplexed, and the machinery would soon come to a standstill, but for certain experienced, unambitious, and unobtrusive members of society." So is it also in the economy of animal life. The work of life is—to paraphrase Mr. Norris's words—for the most part done by habits of which nobody ever thinks. The bodily organization is ostensibly under the control of intellect and reason; but these brilliant qualities would be sorely perplexed, and the machinery would soon come to a standstill, but for certain unobtrusive, habitual activities which are already as well trained in the routine work of life as are the permanent clerks in the routine work of a Government office.

The importance of the establishment of these habitual activities is immense. As the muscular and other responses of ordinary everyday life become habitual, the mind is, so to speak, set free from any special care with regard to their regulation and co-ordination, and can be concentrated on the end to be attained by such activities. The cat that is creeping stealthily upon the bird has all her attention rivetted on the object of her appetence, and has not to trouble herself about the movements of her body and limbs. When the swallows are wheeling over our heads in the summer air, their sweeping curves and graceful evolutions are not the outcome of careful planning, but are just the normal exercise of activities which from long practice have become habitual. To swim, to skate, to cycle, to row, to play the piano or the violin,—all these require our full attention at first. But with practice they become habitual, and during their performance the attention may be devoted to quite other matters. This is a great gain. Without it complex trains of activities could not be performed with ease by man or beast.

When once habits have been firmly established, their normal performance is accompanied by a sense of satisfaction. But if their performance is prevented or thwarted, there arises a sense of want or dissatisfaction. The pining of a caged wild animal for liberty is a craving for the free performance of its habitual activities. In an animal born into captivity the craving is probably less intense, though, for reasons which will presently become evident, it is presumably by no means absent. Animals are, to a very large extent, creatures of habit. Much of the pleasure of their existence lies in the performance of habitual activities. Our zoological gardens, interesting as they are to us, are probably centres of an amount of misery and discomfort, from unfulfilled promptings of habit and instinct, which we can hardly realize.

From habitual activities we may pass by easy steps to those which are instinctive. Both habits and instincts, or, to use a more convenient and satisfactory mode of expression for our present purpose, both habitual and instinctive activities, are based upon innate capacity. But whereas habitual activities always require some learning and practice, and very often some intelligence, on the part of the individual, instinctive activities are performed without instruction or training, through the exercise of no intelligent adaptation on the part of the performer, and either at once and without practice (perfect instincts) or by self-suggested trial and practice (incomplete instincts).[IN]

There is some little difficulty in distinguishing between instinctive activities and reflex actions. Mr. Herbert Spencer defines or describes instinct as compound reflex action. Mr. Romanes defines instinct as reflex action into which there is imported the element of consciousness. But, on the one hand, many instincts involve something more than compound reflex action, since there is an organized sequence of activities; and, on the other hand, the difficulty (which Mr. Romanes admits) or impossibility (as I contend) of applying the criterion of consciousness renders unsatisfactory the introduction of the mental element as distinctive. I would say, therefore, that (1) reflex actions are those comparatively isolated activities which are of the nature of organic or physiological responses to more or less definite stimuli, and which involve rather the several organs of the organism than the activities of the organism as a whole; and that (2) instinctive activities are those organized trains or sequences of co-ordinated activities which are performed by the individual in common with all the members of the same more or less restricted group, in adaptation to certain circumstances, oft-recurring or essential to the continuance of the species.

These instinctive activities may, as I have said, be performed at once and without practice (perfect instincts) or by self-suggested trial and practice (incomplete instincts). Most young mammals require some little practice in the use of their limbs before they are able to walk or run. But young pigs run about instinctively so soon as they are born. Thunberg, the South African traveller, relates, on the testimony of an experienced hunter, the case of a female hippopotamus which was shot the moment she had given birth to a calf. "The Hottentots," he said, "who imagined that after this they could catch the calf alive, immediately rushed out of their hiding-place to lay hold of it; but, though there were several of them, the new-born calf got away from them, and at once made the best of its way to the river."

Even in cases where some practice is apparently necessary, the activities may be, and often are, perfectly instinctive. They cannot, however, be performed immediately on birth, because the nervous and muscular mechanism is not at that time sufficiently developed. They might, perhaps, with advantage be termed "deferred instincts." If time be given for this development, the activities are carried out at once and without practice. Throw a new-born puppy into the river, and, after some helpless floundering, he will be drowned. Throw his brother when fully grown into the river, and, though he may never have been in the water in his life, he will swim to shore. He has not to learn to swim; this is with him an instinctive activity. The dog inherits the power which the boy must with some little difficulty acquire. He probably has to pay no special attention to the muscular adjustments involved. The act is accompanied by consciousness, but not that directed consciousness we call "attention." When the boy has acquired the habit, he is scarcely conscious of the special muscular co-ordinations as he swims across the river; he is only conscious of a desire to pick the water-lilies near the further bank.

Birds, especially those which are called proecoces, in contradistinction from the altrices, which are hatched in a helpless, callow condition, come into the world prepared at once to perform complex activities. Mr. Spalding writes,[IO] "A chicken that had been made the subject of experiments on hearing [having been blindfolded at birth] was unhooded when nearly three days old. For six minutes it sat chirping and looking about it; at the end of that time it followed with its head and eyes the movements of a fly twelve inches distant; at ten minutes it made a peck at its own toes, and the next instant it made a vigorous dart at the fly, which had come within reach of its neck, and seized and swallowed it at the first stroke; for seven minutes more it sat calling and looking about it, when a hive-bee, coming sufficiently near, was seized at a dart, and thrown some distance much disabled. For twenty minutes it sat on the spot where its eyes had been unveiled without attempting to walk a step. It was then placed on rough ground, within sight and call of a hen with a brood of its own age. After standing chirping for about a minute, it started off towards the hen, displaying as keen a perception of the qualities of the outer world as it was ever likely to possess in after-life. It never required to knock its head against a stone to discover that there was 'no road that way.' It leaped over the smaller obstacles that lay in its path, and ran round the larger, reaching the mother in as nearly straight a line as the nature of the ground would permit. This, let it be remembered, was the first time it had ever walked by sight."[IP]

Mr. Spalding's experiments also proved that, even among the altrices, young birds do not require to be taught to fly, but fly instinctively so soon as the bodily organization is sufficiently developed to render this activity possible. He kept young swallows caged until they were fully fledged, and then allowed them to escape. They flew straight off at the first attempt. They exhibited the instinctive power of flight in a perfect but deferred form.

It is, however, among the higher invertebrates—especially among the insects, and of them pre-eminently in the social hymenoptera, ants and bees, that the most remarkable and complete instincts are seen. There is, however, a tendency to ascribe all the habits of ants and bees to instinct, often, as it seems to me, without sufficient evidence that they are performed without instruction, and through no imitation or intelligent adjustment. This is, perhaps, a survival of the old-fashioned view that all the mental activities of the lower animals are performed from instinct, whereas all the activities of human beings are to be regarded as rational or intelligent. In popular writings and lectures, for example, we frequently find some or all of the following activities of ant-life ascribed to instinct: recognition of members of the same nest; powers of communication; keeping aphides for the sake of their sweet secretion; collection of aphid eggs in October, hatching them out in the nest, and taking them in the spring to the daisies, on which they feed, for pasture; slave-making and slave-keeping, which, in some cases, is so ancient a habit that the enslavers are unable even to feed themselves; keeping insects as beasts of burden, e.g. a kind of plant-bug to carry leaves; keeping beetles, etc., as domestic pets; habits of personal cleanliness, one ant giving another a brush-up, and being brushed-up in return; habits of play and recreation; habits of burying the dead; the storage of grain and nipping the budding rootlet to prevent further germination; the habits described by Dr. Lincecum, and to a large extent confirmed by Dr. McCook,[IQ] that Texan ants go forth into the prairie to seek for the seeds of a kind of grass of which they are particularly fond, and that they take these seeds to a clearing which they have prepared, and then sow them for the purpose, six months afterwards, of reaping the grain which is the produce of their agriculture; the collection by other ants of grass to form a kind of soil on which there subsequently grows a species of fungus upon which they feed; the military organization of the ecitons of Central America; and so forth. Now, the description of the habits of ants forms one of the most interesting chapters in natural history. But to lump them together in this way, as illustrations of instinct, is a survival of an old-fashioned method of treatment. That they have to a very large extent an innate basis may be readily admitted. But at present we are hardly in a position to say how far they are instinctive, that is, performed by each individual straight off, and without imitation, instruction, or intelligence; how far habitual, that is, performed after some little training and practice; how far there is the intelligent element of special adaptation to special circumstances; how far they are the result of imitation; to what extent, if any, individual training and instruction are factors in the process.

To put the matter in another way. Suppose that an intelligent ant were to make observations on human activities as displayed in one of our great cities or in an agricultural district. Seeing so great an amount of routine work going on around him, might he not be in danger of regarding all this as evidence of blind instinct? Might he not find it difficult to obtain satisfactory evidence of the establishment of our habits, of the fact that this routine work has to some extent to be learnt? Might he not say (perhaps not wholly without truth), "I can see nothing whatever in the training of the children of these men to fit them for their life-activities. The training of their children has no more apparent bearing upon the activities of their after-life than the feeding of our grubs has on the duties of ant-life. And although we must remember," he might continue, "that these large animals do not have the advantage which we possess of awaking suddenly, as by a new birth, to their full faculties, still, as they grow older, now one and now another of their instinctive activities are unfolded and manifested. They fall into the routine of life with little or no training as the period proper to the various instincts arrives. If learning thereof there be, it has at present escaped our observation. And such intelligence as their activities evince (and many of them do show remarkable adaptation to uniform conditions of life) would seem to be rather ancestral than of the present time; as is shown by the fact that many of the adaptations are directed rather to past conditions of life than to those which now hold good. In the presence of new emergencies to which their instincts have not fitted them, these poor men are often completely at a loss. We cannot but conclude, therefore, that, although shown under somewhat different and less favourable conditions, instinct occupies fully as large a space in the psychology of man as it does in that of the ant, while their intelligence is far less unerring and, therefore, markedly inferior to our own."

Of course, the views here attributed to the ant are very absurd. But are they much more absurd than the views of those who, on the evidence which we at present possess, attribute all the varied activities of ant-life to instinct? Take the case of the ecitons, or military ants, or the harvesting ants, or the ants that keep draught-bugs as beasts of burden: have we sufficient evidence to enable us to affirm that these activities are purely instinctive and not habitual? That they are to a large extent innate, few are likely to deny; but then our own habitual acts have a basis that is, to a very large extent, innate. The question is not whether they have an innate basis, but whether all the varied manoeuvres of the military ants, for example, are displayed to the full without any learning or imitation, without teaching and without intelligence on the part of every individual in the army.[IR]

That in some cases there is something very like a training or education of the ant when it emerges from the pupa condition is rendered probable by the observations of M. Forel. As Mr. Romanes says,[IS] "The young ant does not appear to come into the world with a full instinctive knowledge of all its duties as a member of a social community. It is led about the nest and 'trained to a knowledge of domestic duties, especially in the case of larvÆ.' Later on, the young ants are taught to distinguish between friends and foes. When an ants' nest is attacked by foreign ants, the young ones never join in the fight, but confine themselves to removing the pupÆ; and that the knowledge of hereditary enemies is not wholly instinctive in ants is proved by the following experiment, which we owe to Forel. He put young ants belonging to three different species into a glass case with pupÆ of six other species—all the species being naturally hostile to one another. The young ants did not quarrel, but worked together to tend the pupÆ. When the latter hatched out, an artificial colony was formed of a number of naturally hostile species, all living together after the manner of the 'happy families' of the showmen."

I have said that the varied activities of ants, though they may not in all cases be truly instinctive, are nevertheless the outcome of certain innate capacities. It seems to me necessary to distinguish carefully between innate capacity and instinct. Every animal comes into the world with an innate capacity to perform the activities which have been necessary for the maintenance of the normal existence of its ancestors. This is part of its inherited organization. Only when these activities are performed at the bidding of impulse, through no instruction and from no tendency to imitation, can they, strictly speaking, be termed instinctive. The more uniform the conditions of ancestral life, and the more highly developed the organism when it enters upon the scene of active existence, the more likely are the innate capacities to manifest themselves at once and without training as perfect instincts. Among birds, the proecoces, which reach a high state of development within the egg, and among insects, those which undergo complete metamorphosis, and emerge from the pupa or chrysalis condition fully formed and fully equipped for life, display the greatest tendency to exhibit activities which are truly and perfectly instinctive. But man, whose ancestors have lived and worked under such complex conditions, and who comes into the world in so helpless and immature a state, though his innate capacities are enormous, exhibits but few and rudimentary instincts.

One marked characteristic of many of the habits and instincts of the lower animals is the large amount of blind prevision (if one may be allowed the expression) which they display. By blind prevision I mean that preparation for the future which, if performed through intelligence or reason, we should term "foresight," but which, since it is performed prior to any individual experience of the results, is done, we must suppose, in blind obedience to the internal impulse. The sphex, a kind of wasp-like insect, forms a little mud chamber in which she lays her eggs. She goes forth, finds a spider, stings it in such a way that it is paralyzed but not killed, and places it in the chamber for her unborn young, which she will never see. The hen incubates her eggs, though she may never have seen a chicken in her life. The caterpillars of an African moth weave a collective cocoon as large as a melon. All unite to weave the enveloping husk; each forms its separate cocoon within the shell, and all these separate cocoons are arranged round branch-passages or corridors, by which the moths, when they emerge from the chrysalis condition, may escape. Another caterpillar, that of a butterfly (Thekla) feeds within the pomegranate, but with silken threads attaches the fruit to the branch of the tree, lest, when withered, it should fall before the metamorphosis is complete. An ichneumon fly, mentioned by Kirby and Spence, "deposits its eggs in the body of a larva hidden between the scales of a fir-cone, which it can never have seen, and yet knows where to seek;" and thus provision is made for young which it will never know. Instances of such blind prevision might be quoted by the score. It is idle to speculate as to the accompaniments of consciousness of such acts. If it be asked—May there not be associated with the performance of the instinctive activity of incubation an inherited memory of a generalized chick? we can only answer that we do not know, but that we guess not.[IT]

There is, however, one association, in the case of these and other instincts, which we may fairly surmise to be frequent, though, for reasons to be specified hereafter, it is probably not invariable. Just as we saw to be the case with habits, so too with instinctive activities, their performance is not infrequently associated with pleasurable feeling, their non-performance with pain and discomfort and a sense of craving or want. The animal prevented from performing its instinctive activities is often apparently unquiet, uneasy, and distressed. Hence I said that the animals in our zoological gardens, even if born and reared in captivity, may exhibit a craving for freedom and a yearning to perform their instinctive activities. This craving may be regarded as a blind and vague impulse, prompting the animal to perform those activities which are for its own good and for the good of the race to which it belongs. The satisfaction of the craving, the gratification of the blind impulse, is accompanied by a feeling of relief and ease. Thus where a motive emerges at all into consciousness, that from which we may presume that instinctive activities are performed is not any foreknowledge of their end and purpose, but the gratification of an immediate and pressing need, the satisfaction of a felt want.

We have, so far, been concerned merely with the various kinds of activity presented by men and animals, and with some of their characteristics. The organism, in virtue of its organization, has an inherited groundwork of innate capacity. Surrounding circumstances and commerce with the world draw out and develop the activities which the innate capacity renders possible. First, there are automatic and reflex actions, which are comparatively isolated activities in response to definite stimuli, external or internal. Secondly, there are those organized trains or sequences of co-ordinated activities which are performed by the individual in common with all the members of the same more or less restricted group, in adaptation to certain circumstances, oft-recurring or essential to the continuance of the species. These are the instinctive activities. But no hard-and-fast line can be drawn between them and reflex actions. The instinctive activities may be either perfect or relatively imperfect, according to the accuracy of their adaptation to the purpose for which the activity is performed; but in either case they are carried out without learning or practice. In some cases, however, they cannot be performed until the organization is more perfectly developed than it is at birth; but when the proper time arrives they are perfect, and require no practice; these may be termed "deferred instincts." Where some practice, but only a little, is required, the instinctive activities may be regarded as incomplete; and these pass into those activities which require at first a good deal of practice, learning, and attention, but eventually run off smoothly and without special attention, at times almost or quite unconsciously. These are habitual activities. Finally, we have those activities which are performed in special adaptation to special circumstances. These are intelligent activities.

All of these may be, and the last, the intelligent actions, invariably are, accompanied by consciousness. The habitual activities, and those which are incompletely instinctive, are also, we may presume, accompanied by consciousness during the process of their organization and establishment. It is possible, however, that some of the perfectly instinctive activities may be performed unconsciously. When we consider how perfectly organized such activities are, and when we also remember that perfectly organized habitual activities are frequently in us unconscious, we shall see cause for suspecting that instinctive activities may, at any rate in some cases, be unconscious. No doubt the conditions of consciousness are not well understood. But let us accept Mr. Romanes's suggestion, that a physiological concomitant is ganglionic delay. "Now what," he asks,[IU] "does this greater consumption of time imply? It clearly implies," he answers, "that the nervous mechanism concerned has not been fully habituated to the performance of the response required, and therefore that, instead of the stimulus merely needing to touch the trigger of a ready-formed apparatus of response (however complex this may be), it has to give rise in the nerve-centre to a play of stimuli before the appropriate response is yielded. In the higher planes of conscious life this play of stimuli in the presence of difficult circumstances is known as indecision; but even in a simple act of consciousness—such as signalling a perception—more time is required by the cerebral hemispheres in supplying an appropriate response to a non-habitual experience, than is required by the lower nerve-centres for performing the most complicated of reflex actions by way of response to their habitual experience. In the latter case the routes of nervous discharge have been well worn by use; in the former case these routes have to be determined by a complex play of forces amid the cells and fibres of the cerebral hemispheres. And this complex play of forces, which finds its physiological expression in a lengthening of the time of latency, finds also a psychological expression in the rise of consciousness." Now, since in many instinctive activities the stimulus "merely needs to touch the trigger of a ready-formed apparatus of response," I think that they may be unconscious. And Mr. Romanes thus himself supplies the reason for rejecting his own definition of instinct as "reflex action into which there is imported the element of consciousness." Of course, logically, Mr. Romanes can reply, "It is merely a question of where we draw the line; if the activity is unconscious, it is a reflex action; if conscious, it is an instinct." I think this unsatisfactory, (1) because the criterion of consciousness, from its purely inferential nature, is practically impossible of application with accuracy; (2) because the same series of activities may probably at one time be unconscious and at another time conscious; and (3) because many actions which are almost universally regarded as reflex actions may at times be accompanied by consciousness, and would then have, on Mr. Romanes's view, to be regarded as instincts.

Having made this initial criticism, I may now state that I regard Mr. Romanes's treatment of instinct as most admirable and masterly. Building upon the foundation laid by Charles Darwin, he has worked out the theory of instinct in a manner at once broad and yet minute, lucid and yet close, definite in doctrine and yet not blind to difficulties. If I say that it is a piece of work worthy of the great master whose devoted disciple Mr. Romanes has proved himself, I am according it the highest praise in my power. I have ventured in this volume to criticize some of Mr. Romanes's conclusions in the field of animal intelligence. And lest I should seem to undervalue his work, lest our few divergences should seem to hide our many parallelisms, I take this opportunity of testifying to my great and sincere admiration of the results of his careful and exact observations, his patient and thoughtful inferences, and his lucid and often luminous exposition.

I do not propose to go over the ground so exhaustively covered by Mr. Romanes in his discussion of instinct. I shall first endeavour shortly to set forth his conclusions, and then review the subject in the light of modern views of heredity.

Admitting that some instincts may have arisen from the growth, extension, and co-ordination of reflex actions, Mr. Romanes regards the majority of instincts as of two-fold origin—first, from the natural selection of fortuitous unintelligent activities which chanced to be profitable to the agent (primary instincts); and, secondly, from the inheritance of habitual activities intelligently acquired. These are the secondary instincts, comprising activities which have become instinctive through lapsed intelligence. In illustration of primary instincts, Mr. Romanes cites the instinct of incubation. "It is quite impossible," he says,[IV] "that any animal can ever have kept its eggs warm with the intelligent purpose of hatching out their contents, so that we can only suppose that the incubating instinct began by warm-blooded animals showing that kind of attention to their eggs which we find to be frequently shown by cold-blooded animals.... Those individuals which most constantly cuddled or brooded over their eggs would, other things equal, have been most successful in rearing progeny; and so the incubating instinct would be developed without there ever having been any intelligence in the matter."

Many of the instincts which exhibit what I have termed above "blind prevision" must, it would seem, belong completely or in the main to this class. The instincts of female insects, which lead them to anticipate by blind prevision the wants of offspring they will never see; the instincts of the caterpillars, which lead them to make provision for the chrysalis or imago condition of which they can have no experience; the instinct of a copepod crustacean, which lays its eggs in a brittle-star, that they may therein develop, probably in the brood-sac, and may even destroy the reproductive powers of the host for the future good of her own offspring—these and many others would seem to have no basis in individual experience.

In illustration of the second class of instincts, those due to lapsed intelligence, Mr. Romanes cites the case of birds living on oceanic islands, which at first show no fear of man, but which acquire in a few generations an instinctive dread of him—for the wildness or tameness may become truly instinctive. "If," says Dr. Rae,[IW] "the eggs of a wild duck are placed with those of a tame one under a hen to be hatched, the ducklings from the former, on the very day they leave the egg, will immediately endeavour to hide themselves, or take to the water if there is any water, should any person approach, whilst the young from the tame duck's eggs will show little or no alarm, indicating in both cases a clear instance of instinct or 'inherited memory.'"

It must not be supposed that these two modes of origin are mutually exclusive, and that any particular instinct must belong either to the one class or the other. On the contrary, many instincts have, as it were, a double root—the principle of selection combining with that of lapsing intelligence in the formation of a joint result. Intelligence may thus give a new direction to a primary instinct, and, the intelligent modification being inherited, what is practically a new instinct may arise. Conversely, selection may tend to preserve those individuals which perform some intelligent action, and may, therefore, aid the lapsing of intelligence in establishing and stereotyping an instinct.

Referring the reader to Mr. Romanes's work for the examples and illustrations by which he enforces his views, we may now proceed to consider the subject in the light of recently developed theories of heredity.

We have seen that a school of biologists has arisen who deny the inheritance of acquired characters. But Mr. Romanes's secondary instincts depend upon the inheritance of habits intelligently acquired. By the school of Professor Weismann, therefore (if we may so call it without injustice to Mr. Francis Galton), secondary instincts, in so far as any individual acquisition is concerned, are denied. Opposed to this school are those who lay great stress on the inheritance of acquired characters. Some of them seem driven to the opposite extreme in the matter of instinct, and appear to hold that instincts are entirely (or let us say almost entirely) due to lapsed intelligence. Professor Eimer, of TÜbingen, for example, says,[IX] "I describe as automatic actions those which, originally performed consciously and voluntarily, in consequence of frequent practice, come to be performed unconsciously and involuntarily.... Such acquired automatic actions can be inherited. Instinct is inherited faculty, especially is inherited habit." In his discussion of the subject, Professor Eimer seems to make no express allusion to primary instincts. And he regards at any rate some of those which are classed by Mr. Romanes as primary, as due to lapsed intelligence. "Every bird," he says,[IY] "must, from the first time it hatches its eggs, draw the conclusion that young will also be produced from the eggs which it lays afterwards, and this experience must have been inherited as instinct." He says[IZ] that the infant takes the breast and sucks "in accordance with its acquired and inherited faculties." He believes[JA] that "the original progenitors of our cuckoo, when they began to lay their eggs in other nests, acted by reflection and with design." Regarding the mason-wasps and their allies, which sting larvÆ in the ganglia which govern muscular action, and thus provide their young with paralyzed but living prey, he exclaims,[JB] "What a wonderful contrivance! What calculation on the part of the animal must have been necessary to discover it!" Of the storing instincts of bees he remarks,[JC] "Selection cannot here have had much influence, since the workers do not reproduce. In order to make these favourable conditions constant, insight and reflection on the part of the animals, and inheritance of these faculties, were necessary." And he concludes,[JD] "Thus, according to the preceding considerations, automatic action may be described as habitual voluntary action; instinct, as inherited habitual voluntary action, or the capacity for such action."

Professor Eimer would not probably deny the co-operation of natural selection in the establishment of these instincts, but he throws it altogether into the background. Now, such a view seems to me wholly untenable. Many of the instincts of insects are performed only once in the course of each individual life. Can it be supposed that the weaving of a cocoon by the caterpillar is mainly a matter of lapsed intelligence? Even if we credit the hen bird with the amount of reflection supposed by Professor Eimer, can we grant to the ancestors of the ichneumon fly such far-reaching observation and intelligence as really to foresee (not by blind prevision, but through intelligent foresight) the future development of the eggs which she lays in a caterpillar? Are we to suppose that the instinctive action of the young cuckoo, which, the day after it is hatched, will eject all the other occupants of a hedge-accentor's nest,[JE] can have had its origin in lapsed intelligence? If, because of their purposive character, we are to regard such instincts as of intelligent origin, may we not be told that through intelligent design the pike has beset its jaws, palate, and gill-arches with innumerable teeth, all backwardly directed for the purpose of holding its slippery prey; and the eagle has protected its eye with a bony ring of sclerotic plates, like the holder of an optician's watch-glass? If mimicry in form and colour is due to natural selection, why not mimicry in habits and activities? If structures of a wonderfully purposive character have been evolved without the intelligent co-operation of the organisms which possess them, why not some of the highly purposive activities?

And here the disciple of the school of Professor Weismann will echo and extend the question, and will say, "Yes! why not all instinctive activities? You are ready to admit," he will continue, "that many instincts, wonderfully purposive in their nature, are of primary origin, that is due to natural selection; why, then, invoke any other mode of origin? If lapsed intelligence be excluded in these cases, why introduce it at all? Why not admit, what our theory of heredity demands, that[JF] 'all instinct is entirely due to the operation of natural selection, and has its foundation, not upon inherited experiences, but upon the variations of the germ'?"

Professor Weismann's contention needs much more serious consideration than that of Professor Eimer. I think there is force in the À priori argument (as an À priori argument) that since very complex instincts are probably of primary origin, there is no À priori necessity for the introduction of the hypothesis of lapsed intelligence. Let me first illustrate this further.

A certain beetle (Sitaris) lays its eggs at the entrance of the galleries excavated by a kind of bee (Anthophora), each gallery leading to a cell. The young larvÆ are hatched as active little insects, with six legs, two long antennÆ, and four eyes, very different from the larvÆ of other beetles. They emerge from the egg in the autumn, and remain in a sluggish condition till the spring. At that time (in April) the drones of the bee emerge from the pupÆ, and as they pass out through the gallery the sitaris larvÆ fasten upon them. There they remain till the nuptial flight of the anthophora, when the larva passes from the male to the female bee. Then again they await their chance. The moment the bee lays an egg, the sitaris larva springs upon it. "Even while the poor mother is carefully fastening up her cell, her mortal enemy is beginning to devour her offspring; for the egg of the anthophora serves not only as a raft, but as a repast. The honey, which is enough for either, would be too little for both; and the sitaris, therefore, at its first meal, relieves itself from its only rival. After eight days the egg is consumed, and on the empty shell the sitaris undergoes its first transformation, and makes its appearance in a very different form.... It changes into a white, fleshy grub, so organized as to float on the surface of the honey, with the mouth beneath and the spiracles above the surface.... In this state it remains until the honey is consumed;"[JG] and, after some further metamorphoses, develops into a perfect beetle in August.

Now, it seems to me difficult to understand how, at any stage of this long series of highly adaptive, instinctive activities, lapsed intelligence can have been a factor. And therefore I say, if such a complex series[JH] can have resulted from natural selection and non-intelligent adaptation, I see no À priori reason why any instinct, no matter how complex, should not have had a like origin.

Let us, however, next consider whether Professor Weismann's theory of the origin of instincts necessarily altogether excludes intelligence as a co-operating factor. The essential point on which that theory is absolutely insistent is that what is handed on through inheritance is an innate, and not an individually acquired, character. Now, since intelligent actions are characteristically individual, and performed in special adaptation to special circumstances, it would seem, at first sight, that the intelligent modification of an instinct could not, on Professor Weismann's view, be handed on. Let us consider whether this must be so.

Speaking of ants and bees, Darwin pointed out that their instincts could not possibly have been acquired by inherited habit, since they are performed by neuter insects, that is, by undeveloped females incapable of laying eggs and continuing their race. For a habit to pass into an instinct by inheritance, it is obviously necessary that the organism which performs the habitual actions should be capable of producing offspring by which these actions might be inherited. But in this case the parental forms do not possess these instincts, while the neuter insects which do possess them are sterile.

And how does Mr. Darwin meet this difficulty? "It is lessened, or, as I believe, disappears," he says,[JI] "when it is remembered that selection may be applied to the family as well as to the individual. Breeders of cattle wish the flesh and fat to be well marbled together; an animal thus characterized has been slaughtered, but the breeder has gone with confidence to the same stock, and has succeeded. Such faith may be placed in the power of selection, that a breed of cattle always yielding oxen with extraordinarily long horns could, it is probable, be formed by carefully watching which individual bulls and cows, when matched, produced oxen with the longest horns; and yet no one ox would ever have propagated his kind.... Hence we may conclude that slight modifications of structure or of instinct, correlated with the sterile condition of certain members of the community, have proved advantageous; consequently, the fertile males and females have flourished, and transmitted to their fertile offspring a tendency to produce sterile members with the same modifications. This process must have been repeated many times, until that prodigious amount of difference between the fertile and sterile females of the same species has been produced which we see in many social insects."

Now let us apply this illustration to the case of habits intelligently acquired. Instead of the possession of long horns, suppose the performance of some habitual action be observed in the oxen. Then, by carefully watching which individual bulls and cows, when matched, produced oxen which performed this intelligent habitual action, a breed of cattle always yielding oxen which possessed this habit might, on Darwin's principles, be produced. The intelligence of oxen might in this way be enhanced. Such faith may be placed in the power of selection that a breed of cattle always yielding oxen of marked intelligence could, it is possible, be formed by carefully watching which individual bulls and cows, when matched, produced the most intelligent oxen; and yet no ox would ever have propagated its kind. Regarding, then, a nest of ants or bees as a social community, mutually dependent on each other, and subject to natural selection, that community would best escape elimination in which the queen produced two sets of offspring—one set in which the procreative faculty was predominant to the partial exclusion of intelligence, and another in which intelligent activities were predominant to the exclusion of propagation.

It is possible that I have weakened my case by introducing such a difficult problem as the instincts of neuter insects. And I would beg the reader to remember that this is only incidental. What I wish to indicate is that among the many variations to which organisms are subject, there are variations in their intelligent activities; that these are of elimination value, those animals which conspicuously possess them escaping elimination in its several modes; that those survivors which thus escape elimination are likely to hand on, through inheritance, that intelligence which enabled them to survive; that if, throughout a series of generations, such intelligence be applied to some definite end, nervous channels will tend to be definitely established, and the intelligent activity will more and more readily become habitual; that eventually, through the lapsing of intelligence, these habitual activities may become so fixed and stereotyped as to become instinctive; that intelligence has thus been a factor in the establishment of these instinctive activities; that throughout the sequence there is no inheritance of anything individually acquired, the intelligent variations being throughout of germinal origin; and that, therefore, in the origin of instincts, the co-operation of intelligence and the lapsing of intelligence are not excluded on the principles advocated by Professor Weismann.

What, then, is excluded? Any individually acquired increment, either in the intelligence displayed or the stereotyping process. The subject of instinct and of animal intelligence has not at present been considered at any great length by Professor Weismann, but, judging by the general tenor of his writings, I take it that what he demands is definite proof that such individually acquired increment is actually inherited.

As before indicated in the chapter on "Heredity," such proof it is, from the nature of the case, almost impossible to produce. Suppose that we find evidence of a gradually increasing application of intelligence to some important life-activity, or a more and more defined stereotyping of some incompletely habitual or instinctive action; how are we to prove that the increment in either case is due to the inheritance of individual acquisitions, not to the selection of favourable innate (that is to say, germinal) variations? Such a hopeless task may at once be abandoned.

Are we, then, to leave the question as insoluble? I think not. It is still open to us to consider whether there are any cases in which the inheritance of acquired modifications is a more probable hypothesis than the selection of favourable germinal variations. Now, the acquisition of an instinctive dread of man, and the loss of this instinctive timidity under domestication, seem to be of this kind. And yet I doubt whether the evidence on this head is convincing. For the loss of instinctive timidity, Professor Weismann may invoke the aid of panmixia. But if there is truth in what I have already urged on this head, panmixia will not adequately account for the facts. On the other hand, he may contend that the instinctive dread is not due to the inheritance of individually acquired experience, but to the selection of the wilder birds and animals through the persistent elimination of those which are tame. And in support of this view, he may quote Darwin himself, who says,[JJ] "It is surprising, considering the degree of persecution which they have occasionally suffered during the last one or two centuries, that the birds of the Falklands and Galapagos have not become wilder; it shows that the fear of man is not soon acquired." It is questionable, however, whether this persecution, admittedly occasional, can have much elimination value. There is, however, the element of imitation and instruction to be taken into account, and the difficulty of proving that the timidity is really instinctive. It has frequently been observed that birds become, after a while, quite fearless of trains. Here elimination is practically excluded; but it has to be proved that this fearlessness is truly instinctive. Professor Eimer says,[JK] "In my garden every sparrow and every crow know me from afar because I persecute these birds. Once, in the presence of a friend, I shot a crow from the roof of my house, while the pigeons and starlings on the same roof, to the great astonishment of my friend, to whom I had predicted it, remained perfectly quiet. They had learned by frequent experience at what my gun was aimed, and knew that it did not threaten them." There is nothing in this interesting observation, however, to show that what the pigeons had learnt had, by inherited experience, become instinctive. And Professor Weismann will not, in all probability, be prepared to accept as a logical inference "that this instinct of fear, because it can be dispelled by experience, must be founded on inherited, acquired experience."[JL]

Fully admitting, then, that this is a matter of relative probability, and that the observations and inferences in this matter are not by themselves convincing, I still think that the balance of probability is here on the side of some inheritance of experience. Take next such an instinctive habit as that which dogs display of turning round in a narrow circle ere they lie down. In its origin the instinct probably arose with the object of preparing a couch in the long grass. Now, is this habit of elimination value? Can we suppose that it arose through the elimination of those ancestral animals which failed to perform this habit? I find it difficult to accept this view, though it is just possible that the animals which did this thereby escaped the observation of their enemies. It is also possible that this originally was a merely purposeless habit, a strange trick of manner, which has been inherited, and rendered constant and fixed. Here again, however, I think the balance of probability is that the habit was intelligently acquired and inherited.

I have before drawn attention to the more or less incompletely instinctive avoidance, by birds and lizards, of insects with warning coloration. That the avoidance is not perfectly instinctive is shown by the fact that young birds sometimes taste these caterpillars or insects. But a very small basis of experience, often a single case, is sufficient to establish the association. And in young chicks the avoidance of bees and wasps seems to be perfectly instinctive. The effects on the young birds, however, can hardly be of elimination value. Mr. Poulton offered unpalatable insects "to animals from which all other food was withheld. Under these circumstances, the insects were eaten, although often after many attempts, and evidently with the most intense disgust."[JM] I have caused bees to sting young chickens; the result was extreme discomfort, but in no cases permanent injury or death. If, then, the instinct is not of elimination value, that is to say, not such as to save the possessors from elimination, how can it have been established by natural selection? And if not due to natural selection, to what can it be due, save inherited antipathy?

Natural selection is such a far-reaching and ubiquitous factor in organic evolution, that it is not likely that many cases can be found in which the play of elimination can be rigidly excluded. But there are not a few in which elimination does not appear to be the most important factor. Mr. G. L. Grant has recently observed that the sparrows near Auckland, New Zealand, have taken to burrowing holes in sand-cliffs, like the sand-martin. The cliff-swallow of the Eastern United States has almost ceased to build nests in the cliffs, like its progenitors, and now avails itself of the protection afforded by the eaves of houses. The surviving beavers in Europe are said to have abandoned the instinct of building huts and dams. The race being no longer sufficiently numerous to live in communities, the survivors live in deep burrows. In Russian Lapland, under the persecution of hunters, the reindeer are reported to be abandoning the tundras, or open lichen-covered tracts, for the forests. The kea (Nestor notabilis), a brush-tongued parrot of New Zealand, which normally feeds on honey, fruits, and berries, has, since the introduction of sheep, taken to a carnivorous diet. It is said to have begun by pecking at the sheep-skins hung out to dry; subsequently it began to attack living sheep; and now it has learnt to tear its way down to the fat which surrounds the kidneys. This habit, far from being the result of elimination, is rapidly leading to the elimination of the bird that has so strangely adopted it.

Now, although in these cases elimination has, I think, been a quite subordinate factor, I do not adduce them as convincing evidence that acquired habits are hereditary. Instruction and imitation in each successive generation may well have come into play. There is no proof that they are even incompletely instinctive. But I think that these are the kinds of activities, renewed and careful observations and, if possible, experiments on which, may lead to more decisive results. It would probably not be difficult to ascertain how far the carnivorous habit of the kea has become hereditary, and how far it is performed in the absence of instruction and without the possibility of imitation.

I confess that when I look round upon the varied habits of birds and mammals, when I see the frigate bird robbing the fish-hawk of the prey that it has captured from the sea, the bald-headed chimpanzee adopting a diet of small birds, a Semnopithecus in the Mergui Archipelago eating crustacea and mollusca, and the koypu, a rodent, living on shell-fish; when I consider the divergence of habits in almost every group of organisms, the ground-pigeons, rock-pigeons, and wood-pigeons, seed-eating pigeons and fruit-eating pigeons; the carrion-eating, insect-eating, and fruit-eating crows; the aquatic and terrestrial kingfishers, some living on fish, some on insects, some on reptiles;[JN] the divergent habits of the ring-ousel and the water-ousel; and the peculiar habits of blood-sucking bats;—when I see these and a thousand other modifications and divergences of habit, I question whether the theory that they have all arisen through the elimination of those forms which failed to possess them may not be pushed too far; I am inclined to believe that the inheritance of acquired modifications has been a co-operating factor. It is not enough to say that these habits are all useful to their several possessors. It has to be shown that they are of elimination value—that their possession or non-possession has made all the difference between survival and elimination.

On the whole, then, as the result of a careful consideration of the subject of instinctive and habitual activities, and in accordance with my general view of organic evolution as set forth in previous chapters, I am disposed to accept the inheritance of individually acquired modifications of habit as a working hypothesis. I do not think that absolutely convincing evidence thereof can at present be produced. But to the best of my judgment, the probabilities are in favour of the inheritance of modifications of existing activities, due to intelligence, instruction, and imitation; always provided that the exercise of these modified activities is sufficiently frequent and definite to give rise to habits in the individual.

I recognize three factors in the origin of instinctive activities—

1. Elimination through natural selection.

2. Selection through preferential mating.

3. The inheritance of individually acquired modifications.

Of these I consider the first quite incontrovertible; the second as highly probable; and the third as probable in a less degree. In all three, intelligence may or may not have been a factor. Some of the habits which have survived elimination under the first factor may have been originally intelligent, some of them from the first unintelligent. Some of the love-antics (so called), which, through their tendency to excite sexual appetence in the female, have been selected under the second factor, may have had a basis in intelligence; many of them probably have not. And though the great majority of individually acquired modifications of habits have owed their origin to intelligent direction, still it is conceivable that some of them have not. An animal may have been forced by circumstances to modify its habits, without any exercise of intelligence; and this modification, forced, through changed conditions, upon all the members of a species, may, through inheritance, have passed into the stereotyped condition of an instinct. Under each factor, then, we have two several categories.

In all cases, however, where intelligence has been a co-operating factor, this intelligence has lapsed so soon as the activity became truly instinctive.

From the co-operation of the factors it is almost impossible to give examples which shall illustrate the exclusive action of any one. The following table must therefore be regarded as indicating the probable predominance of the factor indicated:—

In speaking of the instinct of caterpillars spinning cocoons as unintelligent, I am regarding the final purpose of the activity. Intelligence may very possibly have come into play in modifying the details of procedure. In giving the drumming of snipe as an example of unintelligent activities furthered by selection, I am assuming that it has a sexual import, and that the activity correlated with a narrowing of the tail-feathers was not, in its inception, intelligently performed with the object of exciting sexual appetence in the hen. The case of the ants of Siam is given by Mr. Romanes,[JO] on the authority of LonbiÈre, who says "that in one part of that kingdom, which lies open to great inundations, all the ants made their settlements upon trees; no ants' nests are to be seen anywhere else." Now, this modification of habits may have been the result of intelligence; or it may have been forced upon the ants by circumstances. The floods drove them on to the trees; the instinctive impulse to build a settlement was imperative; hence the settlement had to be formed on the trees, because the ground was flooded. The difficulty of ascertaining whether intelligence has or has not been a factor is simply part of the inherent difficulty of comparative psychology—a difficulty on which sufficient stress has already been laid in an earlier chapter.

The great majority of the instinctive activities of animals have arisen through a co-operation of the factors, and it is exceedingly difficult in any individual case to assign to the factors their several values.

And here we must once more notice that the separation off of the instinctive activities from the other activities of animals is merely a matter of convenience in classification. In the living organism the activities—automatic actions, reflex actions, incompletely and perfectly established instincts, habits, and intelligent activities—are unclassified and commingled. They are going on at the same time, shading the one into the other, untrammelled by the limits imposed by a scientific method of treatment.

Once more, too, we must notice that the activities of animals are essentially the outcome and fulfilment of emotional states. When the emotional sensibility is high, the resulting activities are varied and vigorous. As we have before seen, this high state of emotional sensibility is correlated with a highly charged and sensitive condition of the organic explosives elaborated by the plasmogen of the cells. After repose, and at certain periodic times, this state of exalted sensibility is apt to occur. It is exemplified in the so-called instinct of play, which manifests itself in varied activities in the early morning, in early life, and in the returning warmth of spring—at such times, in fact, as the life-tide is in full flood.

But perhaps the activities which result from a highly wrought state of sensibility are best seen at the periodic return of sexual appetence or impulse in animals of various grades of life and intelligence. Many organisms, at certain periods of the year, and in presence of their mates, are thrown into a perfect frenzy of sexual appetence. The love-antics of birds have been so frequently described that I will merely quote from Darwin[JP] Mr. Strange's account of the satin bower-bird: "At times the male will chase the female all over the aviary, then go to the bower, pick up a gay feather or a large leaf, utter a curious kind of note, set all his feathers erect, run round the bower, and become so excited that his eyes appear ready to start from his head; he continues opening first one wing, and then the other, uttering a low, whistling note, and, like the domestic cock, seems to be picking up something from the ground, until at last the female goes gently towards him." Instances might be quoted from almost all classes of the animal kingdom. Many fish display "love-antics," for example, the gay-suited, three-spine stickleback, whose excitement is apparently intense. Newts display similar activities. Even the lowly snail makes play with its love-darts (spiculÆ amoris), practical tangible darts of glistening carbonate of lime. Mr. George W. Peckham has recently described[JQ] the extraordinary "love-dance" of a spider (Saitis pulex). "On May 24 we found a mature female, and placed her in one of the larger boxes; and the next day we put a male in with her. He saw her as she stood perfectly still, twelve inches away; the glance seemed to excite him, and he at once moved towards her; when some four inches from her he stood still, and then began the most remarkable performances that an amorous male could offer to an admiring female. She eyed him eagerly, changing her position from time to time, so that he might be always in view. He, raising his whole body on one side by straightening out the legs, and lowering it on the other by folding the first two pairs of legs up and under, leaned so far over as to be in danger of losing his balance, which he only maintained by sidling rapidly towards the lowered side. The palpus, too, on this side was turned back to correspond to the direction of the legs nearest it. He moved in a semicircle for about two inches, and then instantly reversed the position of the legs, and circled in the opposite direction, gradually approaching nearer and nearer to the female. Now she dashes towards him, while he, raising his first pair of legs, extends them upward and forward as if to hold her off, but withal slowly retreats. Again and again he circles from side to side, she gazing towards him in a softer mood, evidently admiring the grace of his antics. This is repeated until we have counted a hundred and eleven circles made by the ardent little male. Now he approaches nearer and nearer, and when almost within reach whirls madly around and around her, she joining and whirling with him in a giddy maze. Again he falls back and resumes his semicircular motions, with his body tilted over; she, all excitement, lowers her head and raises her body, so that it is almost vertical; both draw nearer; she moves slowly under him, he crawling over her head, and the mating is accomplished."

It can scarcely be doubted that such antics, performed in presence of the female and suggested at sight of her, serve to excite in the mate sexual appetence. If so, it can, further, scarcely be doubted that there are degrees of such excitement, that certain antics excite sexual appetence in the female less fully or less rapidly than others; yet others, perhaps, not at all. If so, again, it can hardly be questioned that those antics which excite most fully or most rapidly sexual appetence in the female will be perpetuated through the selection of the male which performs them. This is sexual selection through preferential mating. And, I think, the importance of these activities, their wide range, and their perfectly, or at any rate incompletely instinctive nature, justifies me in emphasizing this factor in the origin of instinctive activities. It has hitherto, I think, not received the attention it deserves in discussions of instinct.

A few more words may here be added to what has already been said on the influence of intelligence on instinct. The influence may be twofold—it may aid in making or in unmaking instincts. We have seen that instincts may be modified through intelligent adaptation. A little dose of judgment, as Huber phrased it, often comes into play. The cell-building instinct of bees is one which is remarkably stereotyped; and yet it may be modified in intelligent ways to meet special circumstances. When, for example, honey-bees were forced to build their comb on the curve, the cells on the convex side were made of a larger size than usual, while those on the concave side were smaller than usual. Huber constrained his bees to construct their combs from below upwards, and also horizontally, and thus to deviate from their normal mode of building. The nest-construction of birds, again, may be modified in accordance with special circumstances. And, perhaps, it is scarcely too much to say that, whenever intelligence comes on the scene, it may be employed in modifying instinctive activities and giving them special direction.

Now, suppose the modifications are of various kinds and in various directions, and that, associated with the instinctive activity, a tendency to modify it indefinitely be inherited. Under such circumstances intelligence would have a tendency to break up and render plastic a previously stereotyped instinct. For the instinctive character of the activities is maintained through the constancy and uniformity of their performance. But if the normal activities were thus caused to vary in different directions in different individuals, the offspring arising from the union of these differing individuals would not inherit the instinct in the same purity. The instincts would be imperfect, and there would be an inherited tendency to vary. And this, if continued, would tend to convert what had been a stereotyped instinct into innate capacity; that is, a general tendency to certain activities (mental or bodily), the exact form and direction of which is not fixed, until by training, from imitation or through the guidance of individual intelligence, it became habitual. Thus it may be that it has come about that man, with his enormous store of innate capacity, has so small a number of stereotyped instincts.

But while intelligence, displayed under its higher form of originality, may, in certain cases, lead to all-round variation, tending to undermine instinct and render it less stereotyped, intelligence, under its lower form of imitation, has the opposite tendency. For young animals are more likely to imitate the habits of their own species than the foreign habits of other species, and such imitation would therefore tend towards uniformity.

Imitation is probably a by no means unimportant factor in the development of habits and instincts. Mr. A. R. Wallace, in his "Contributions to the Theory of Natural Selection," contends that the nest-building habit in birds is, to a large extent, kept constant by imitation. The instinctive motive is there, but the stereotyped form is maintained through imitation of the structure of the nest in which the builders were themselves reared. Mr. Weir, however, writing to Mr. Darwin, in 1868, says in a letter, which Mr. Romanes quotes,[JR] "The more I reflect on Mr. Wallace's theory, that birds learn to make their nests because they have themselves been reared in one, the less inclined do I feel to agree with him.... It is usual with canary-fanciers to take out the nest constructed by the parent birds, and to place a felt nest in its place, and, when the young are hatched and old enough to be handled, to place a second clean nest, also of felt, in the box, removing the other. This is done to prevent acari. But I never knew that canaries so reared failed to make a nest when the breeding-time arrived. I have, on the other hand, marvelled to see how like a wild bird's the nests are constructed. It is customary to supply them with a small set of materials, such as moss and hair. They use the moss for the foundation, and line with the finer materials, just as a wild goldfinch would do, although, making it in a box, the hair alone would be sufficient for the purpose. I feel convinced nest-building is a true instinct." On the other hand, Mr. Charles Dixon, quoted[JS] in Mr. Wallace's "Darwinism," speaking of chaffinches which were taken to New Zealand and turned out there, says, "The cup of the nest is small, loosely put together, apparently lined with feathers, and the walls of the structure are prolonged for about eighteen inches, and hang loosely down the side of the supporting branch. The whole structure bears some resemblance to the nests of the hang-birds (IcteridÆ), with the exception that the cavity is at the top. Clearly these New Zealand chaffinches were at a loss for a design when fabricating their nest. They had no standard to work by, no nests of their own kind to copy, no older birds to give them any instruction, and the result is the abnormal structure I have just described."

There is more evidence in favour of the view that the song of birds is, in part at least, imitative. That it has an innate basis is certain; and that it may be truly instinctive is shown by Mr. Couch's observation of a goldfinch which had never heard the song of its own species, but which sang the goldfinch-song, though tentatively and imperfectly. On the other hand, imitation is undoubtedly a factor. The Hon. Daines Barrington says (1773), "I have educated nestling linnets under the three best singing larks—the skylark, woodlark, and titlark—every one of which, instead of the linnet's song, adhered entirely to that of their respective instructors. When the note of the titlark linnet was thoroughly fixed, I hung the bird in a room with two common linnets for a quarter of a year. They were in full song, but the titlark linnet adhered steadfastly to that of the titlark." Mr. Wallace, who quotes this, adds,[JT] "For young birds to acquire a new song correctly, they must be taken out of hearing of their parents very soon, for in the first three or four days they have already acquired some knowledge of the parent's notes, which they afterwards imitate." Dureau de la Malle, as quoted by Mr. Romanes,[JU] describes how he taught a starling the "Marseillaise," and from this bird all the other starlings in a canton to which he took it are stated to have learned the air!

That dogs, monkeys, and other mammalia have powers of imitation needs no illustration. And when we remember that it is only the imitation of strange and unusual actions that arrests our attention, while the imitation of normal activities is likely to pass unnoticed, we may, I think, fairly surmise that imitation is by no means an unimportant factor in the acquisition and development of habits. And where the young animal is surrounded during the early plastic and imitative period of life by its own kith and kin, imitation will undoubtedly have a conservative tendency.

The education of young animals by their parents has also a conservative tendency. Mr. Spalding's observations show that the flight of birds is instinctive; but the parent birds normally aid the development of the instincts by instruction. Ants, as we have seen, are instructed in the business of ant-life. Dogs and cats train their young. And Darwin tells us, on the authority of Youatt,[JV] that lambs turned out without their mothers are very liable to eat poisonous herbs.

We may say, then, with regard to the influence of intelligence on instinctive activities, that it may lead them to vary along certain definite lines of increased adaptation; that it may, in some cases, lead them to vary along divergent lines, and hence tend to render stereotyped instincts more plastic; and that, through imitation and instruction, it may tend to render instinctive habits more uniform in a community, and hence, if the habits are tending to vary under changed circumstances in a given direction, may tend to draw the habits of all the members of the community in that given direction.

And with regard to the more general question of the variation of habits and instincts, we may say that, in addition to those variations in the origin and direction of which intelligence is a factor, there are other variations which take their origin without the influence of intelligence under the stress of changing circumstances, and yet others which may arise as we say "fortuitively" or "by chance," that is, from some cause or causes whereof we are at present ignorant, and which do not appear to be evoked directly by the stress of environing circumstances.

Granting, however, the existence of these variations in whatsoever way arising, and granting the influence of natural selection, of sexual selection, and perhaps of the inheritance of individually acquired modifications, those variations which are for the good of the race or species in which they occur will have a tendency to be perpetuated, while those which are detrimental will be weeded out and will tend to disappear.

Passing on now to consider the characteristics of those activities which we term "intelligent," we may first notice what Mr. Charles Mercier, in "The Nervous System and the Mind," calls the four criteria of intelligence. Intelligence is manifested, he says, first, in the novelty of the adjustments to external circumstances; secondly, in the complexity; thirdly, in the precision; and fourthly, in dealing with the circumstances in such a way as to extract from them the maximum of benefit.

Now, I think it is clear that, when it is our object to distinguish intelligent from instinctive activities, the precision of the adjustment cannot be regarded as a criterion of intelligence. Many instinctive acts are wonderfully precise. The sphex is said to stab the spider it desires to paralyze with unerring aim in the central nerve-ganglion. Other species, which paralyze crickets and caterpillars, pierce them in three and nine places respectively, according to the number of the ganglia. And yet this seems to be a purely instinctive action. So, too, to take but one more example, there is surely no lack of precision in the cell-making instinct of bees. We may say, then, that, granting that an action is intelligent, the precision of the adjustment is a criterion of the level of intelligence; but that, since there may be instinctive actions of wonderful precision, this criterion is not distinctive of intelligence. Nay, more, there are many reflex actions of marvellous precision and accuracy of adjustment; and there can be no question of intelligence, individual or ancestral, in many of these.

Nor can we regard prevision (which is sometimes advanced as a criterion of intelligence) as specially distinctive of intelligent acts regarded objectively in the study of the activities of animals. For, as we have already seen, there are many instincts which display an astonishing amount of what I ventured to term "blind prevision"—instance the instinctive regard for the welfare of unborn offspring, and the instinctive preparation for an unknown future state in the case of insect larvÆ.

Nor, again, is the complexity of the adjustment distinctive of intelligence as opposed to instinct. The case of the sitaris, before given, the larva of which attaches itself to a male bee, passes on to the female, springs upon the eggs she lays, eats first the egg and then the store of honey,—this case, I say, affords us a series of sufficiently marked complexity. This instinct, the paralyzing, but not killing outright, of prey by the sphex; the marvellous economy of wax in the cell-building of the honey-bee; the affixing to their body, by crabs, of seaweed (Stenorhynchus), of ascidians (an Australian Dromia), of sponge (Dromia vulgaris), of the cloaklet anemone (Pagurus prideauxii); and other cases too numerous for citation;—these show, too, that the circumstances may be dealt with in such a way as to extract from them the maximum of benefit, probably without intelligence. It would be quite impossible intelligently to improve upon the manner of dealing with the circumstances displayed in many instinctive activities, even those which we have reason to believe were evolved without the co-operation of intelligence.

There remain, therefore, the novelty of the adjustment and the individuality displayed in these adjustments. And here we seem to have the essential features of intelligent activities. The ability to perform acts in special adaptation to special circumstances, the power of exercising individual choice between contradictory promptings, and the individuality or originality manifested in dealing with the complex conditions of an ever-changing environment,—these seem to be the distinctive features of intelligence. On the other hand, in instinctive actions there seems to be no choice; the organism is impelled to their performance through impulse, as by a stern necessity; they are so far from novel that they are performed by every individual of the species, and have been so performed by their ancestors for generations; and, in performing the instinctive action, the animal seems to have no more individuality or originality than a piece of adequately wound clockwork.

It may be said that, in granting to animals a power of individual choice, we are attributing to them free-will; and surely (it may be added), after denying to them reason, we cannot, in justice and in logic, credit them with this, man's choicest gift. I shall not here enter into the free-will controversy. I shall be content with defining what I mean by saying that animals have a power of individual choice. Two weather-cocks are placed on adjoining church pinnacles, two clouds are floating across the sky, two empty bottles are drifting down a stream. None of these has any power of individual choice. They are completely at the mercy of external circumstances. On the other hand, two dogs are trotting down the road, and come to a point of divergence; one goes to the right hand, the other to the left hand. Here each exercises a power of individual choice as to which way he shall go. Or, again, my brother and I are out for a walk, and our father's dog is with us. After a while we part, each to proceed on his own way. Pincher stands irresolute. For a while the impulse to follow me and the impulse to follow my brother are equal. Then the former impulse prevails, and he bounds to my side. He has exercised a power of individual choice. If any one likes to call this yielding to the stronger motive an exercise of free-will, I, for one, shall not say him nay. What I wish specially to notice about it is that we have here a sign of individuality. There is no such individuality in inorganic clouds or empty bottles. Choice is a symbol of individuality; and individuality is a sign of intelligence.

But though I decline here to enter into the free-will controversy, I may fairly be asked where I place volition in the series between external stimulus and resulting activity; and what I regard as the concomitant physiological manifestation. I doubt whether I shall be able to say anything very satisfactory in answer to these questions. I shall have to content myself with little more than stating how the problem presents itself to my mind.

I believe that volition is intimately bound up and associated with inhibition. I go so far as to say that, without inhibition, volition properly so called has no existence. When the series follows the inevitable sequence—

Stimulus: perception: emotion: fulfilment in action

—the act is involuntary. And such it must ever have remained, had not inhibition been evolved, had not an alternative been introduced, thus—

At the point of divergence I would place volition. Volition is the faculty of the forked way. There are two possibilities—fulfilment in action or inhibition. I can write or I can cease writing; I can strike or I can forbear. And my poor little wounded terrier, whose gashed side I was sewing up, clumsily, perhaps, but with all the gentleness and tenderness I could command, could close his teeth on my hand or could restrain the action.

I have here, so to speak, reduced the matter to its simplest expression. It is really more complex. For volition involves an antagonism of motives, one or more prompting to action, one or more prompting to restraint. The organism yields to the strongest prompting, acts or refrains from acting according as one motive or set of motives or the other motive or set of motives prevails; in other words, according as the stimuli to action or the inhibitory stimuli are the more powerful.

And then we must remember that the perceptual volition of animals becomes in us the conceptual volition of man. An animal can choose, and is probably conscious of choosing. This is its perceptual volition. Man not only chooses, and is conscious of choosing, but can reflect upon his choice; can see that, under different circumstances, his choice would have been different; can even fancy that, under the same circumstances (external and internal), his choice might have been different. This is conceptual volition. Just as Spinoza said that desire is appetence with consciousness of self; so may we say that the volition of contemplative man is the volition of the brute with consciousness of self. No animal has consciousness of self; that is to say, no animal can reflect on its own conscious states, and submit them to analysis with the formation of isolates. Self-consciousness involves a conception of self, persistent amid change, and isolable in thought from its states. It involves the isolation in thought of phenomena not isolable in experience. We can think about the self as distinct from its conscious states and the bodily organization; but they are no more separable in experience than the rose is separable from its colour or its scent. Such isolation is impossible to the brute. An animal is conscious of itself as suffering, but the consciousness is perceptual. There is no separation of the self as an entity distinct from the suffering which is a mere accident thereof; no conception of a self which may suffer or not suffer, may act or may not act, may be connected with the body or may sever that connection. Just as there is a vast difference between the perception of an object as here and not there, of an occurrence as now and not then, of a touch as due to a solid body; and the conception of space, time, and causation; so is there a vast difference between a perception of an injury as happening to one's self, and a conception of self as the actual or possible subject of painful consciousness. This difference is clearly seen by Mr. Mivart, who therefore speaks of the consentience of brutes as opposed to the consciousness of man. Consciousness he regards as conceptual; consentience as perceptual.[JW] And, as before stated, I should be disposed to accept his nomenclature, were it not for its philosophical implications. For Mr. Mivart regards the difference between consciousness and consentience as a difference in kind, whereas I regard it as a generic difference. I believe that consentience (perceptual consciousness) can pass and has passed into consciousness (conceptual consciousness); but Mr. Mivart believes that between the two there is a great gulf fixed, which no evolutionary process could possibly bridge or span.

The perceptual volition of animals, then, is a state of consciousness arising when, as the outcome of perception and emotion, motor-stimuli prompting to activity conflict with inhibitory stimuli restraining from activity. The animal chooses or yields to the stronger motive, and is conscious of choosing. But it cannot reflect upon its choice, and bother its head about free-will. This involves conceptual thought. When physiologists have solved the problem of inhibition, they will be in a position to consider that of volition. At present we cannot be said to know much about it from the physiological standpoint.

Still, as before indicated, the fact of inhibition is unquestionable and of the utmost importance. It has before been pointed out that through inhibition, through the suppression or postponement of action, there has been rendered possible that reverberation among the nervous processes in the brain which is the physiological concomitant of Æsthetic and conceptual thought. We have just seen that, in association with inhibition, the faculty of volition has been developed. And we may now notice that the postponement or suppression of action is one of the criteria of intelligent as opposed to instinctive or impulsive activities. This is, however, subordinate to the criterion of novelty and individuality.

Granting, then, that an action is shown to be intelligent from the novelty of the adjustments involved, and from the individuality displayed in dealing with complex circumstances (instinctive adjustments being long-established and lacking in originality), we may say that the level of intelligence is indicated by the complexity of the adjustments; their precision; the rapidity with which they are made; the amount of prevision they display; and in their being such as to extract from the surrounding conditions the maximum of benefit.

Before closing this chapter, I will give a classification of involuntary and voluntary activities:—

In the involuntary acts classed as automatic and reflex, the initiation and the result may be accompanied by consciousness, but the intermediate mental link which answers to the motive in higher activities is, I think, unconscious. In habitual and instinctive activities the consciousness of the percept and the impulse may in some cases have become evanescent, or, to use G. H. Lewes's phrase, have lapsed. In the case of some instincts, originating by the natural selection of unintelligent activities, the perceptual element may never have emerged, and the initiation may have been a mere sense-stimulus.

The division of voluntary activities into perceptual and conceptual follows on the principles adopted and developed in this work. As to the terminology employed, I agree with Mr. S. Alexander[JX] that it is convenient to reserve the terms "desire" and "conduct" for use in the higher conceptual plane. Animals, I believe, are incapable of this higher desire and this higher conduct. It only remains to note that it is within the limits of the fourth class (of voluntary activities initiated by concepts) that morality takes its origin. Morality is a matter of ideals. Moral progress takes its origin in a state of dissatisfaction with one's present moral condition, and of desire to reach a higher standard. The man quite satisfied with himself has not within him this mainspring of progress. The chief determinant of the moral character of any individual is the ideal self he keeps steadily in view as the object of moral desire—the standard to be striven for, but never actually attained.