Chapter VII: The Evolution of Animal Behaviour (2)

So far, then, we reach the following conclusion: that if we classify the behaviour of the higher and more intelligent animals under two heads, the one comprising all those acts which are of direct biological value in enabling the animal to escape elimination under the immediate stress of the struggle for existence, and the other including all those acts which are of indirect preparatory or educative value, the latter, which are under their biological aspect not less important than the former, are under their psychological aspect of perhaps even greater importance. For the conditions of actual struggle are not those under which mental development could most easily be furthered, though they are those in which it is most effectually tested. Hence, the more intelligent animals pass through a period during which they are more or less shielded from the incidence of natural selection by their parents, and this is the period of play and of psychological education. And the tendency to play is so far organic, in that it is dependent on inherited instinctive propensities, and so far psychological in that it is accompanied by a felt want, which constitutes a conative impulse finding its appropriate end in the consciousness of satisfaction. But play--if we accept the term as the group-name for all these modes of behaviour which fall under our second class, those of indirect biological value--does not cease with the period of youth; it occupies all the intervals in the more serious business of animal life. And no discussion of animal behaviour can be adequate which does not assign to this class its due place, alike in biological and in psychological evolution.

The whole value of experience lies in the linkage and coalescence of the data afforded to consciousness. It is true that an inherited nervous system supplies the organic conditions of that physiological linkage and functional coalescence of which experience is the psychological expression. It is true that this physical integration secures a ready-made grouping of the conscious data which are the concomitants of orderly molecular changes in the brain or analogous sensorium. Still, it also remains true that the value of experience lies in the further linkage and coalescence that is acquired by the individual in the course of what we may fitly call its education. Every step in this education gets its psychological sanction through the satisfaction it affords in consciousness; and the time of acquisition is not during the stress of examination in the actual struggle for existence, but rather in the youthful period and in the subsequent intervals of preparation and practice during the play-time of animal life.

The examination analogy--if, indeed, it may not be rightly regarded as something more than an analogy--may be pressed a little further as a means of fixing our attention on two points which are worthy of consideration. The first is that, in the preparation for the examination, specific practice as much of it is, cramming is not the system exemplified by the higher animals. A good all-round education in the acquisition of conscious situations more or less coalescent into a unified system of experience, and in their effective utilization without unnecessary delay and bungling along more or less converging lines of practical behaviour; this is what secures a “pass” in survival, especially where the circumstances of life have reached a considerable degree of complexity. The instinctive act, with its relatively definite response to a question which is almost certain to be set to every candidate for survival, is that, which is the analogue in behaviour to the result of a system of cram. Organic nature does employ this system in the lower classes of her school; definite responses are ground into merely instinctive types generation after generation, and the right answers are given, automatically and unintelligently, whenever the oft-recurrent questions are set. But this will not do when the questions require the exercise of intelligence, when they are of the nature of problems, with just those delicate but not unimportant shades of difference which baffle the candidate who has been drilled in a merely mechanical fashion. Hence the cramming of instinct does not suffice for animals whose environment presents problems of greater variety and greater complexity. Intelligence is required to meet the particular combinations as they arise. The greyhound, which is loosed on a hare, has never seen that hare run in exactly that way over that special tract of country. But he has been trained in such situations, and is thus prepared to meet the special problem in its details as they present themselves in the light of the experience he has gained of other like problems. And his skill in pursuit has not only been gained through education in coursing. In a thousand ways, as puppy and dog, he has learnt how to use well those sinewy limbs. The training of his whole life is brought to bear on the question immediately before him.

The general bearing of these facts is obvious. Play, as a means of animal education, is varied, and has for its end all-round training of the animal mind in its sphere of operation. Although there are some specific propensities, certain observable trends of behaviour, as in hunting-play, courtship-play, and the like, we must not expect, nor do we find, anything like stereotyped definiteness of conative activity. We find that freedom and elasticity in animal education which is, perhaps, more often advocated than carried into practice in human education.

The second point arising out of the examination analogy is, that its range determines the level of preparation therefor. It is, for animals, a practical examination, not a theoretical. Not a single question is set demanding an explanation. The problems are such as can be solved by intelligence, not such as require the exercise of reason, as we have used the term in foregoing pages. These higher problems are only set when the sixth form is reached, and there is no conclusive evidence that any animals get into the sixth. This, however, is entirely a question of evidence, and many of us will be glad to welcome them there, if proved ability to deal reflectively with ideational questions justifies their promotion.

If any of them do belong to this form, they have probably got there through play. For in the stress of the actual examination there is not much time for reflection. Or perhaps we may rather say that, not in actual struggle, and not in active preparation for it in play-time, but in intervals of leisure between both, when the animal lies quietly turning over in his mind we know not what, will experience be reviewed, and generalizations drawn as to the why of events in this strange world. Probably the animal accepts things as they are, and does not trouble about their explanation. But it may not be so. At any rate, if animals lack the means of descriptive inter-communication, and have no words as concrete pegs on which to hang abstract ideas, their explanations cannot be carried far. Theories without the power of disputation would be a poor solace in leisure moments.

One more point may be noticed with regard to the psychological aspect of the evolution of behaviour--the reciprocal action of intelligence. It is the intelligence of others that introduces so much variety and complexity into the environment. Hunters and hunted, combatants, rivals, mate and mate, enemies or companions in their varied aspects, introduce through their intelligence complications which only intelligence can meet. And, as intelligence begets intelligence, so do emotional attitudes beget answering emotional states. Psychological evolution translated into practical behaviour gives rise to situations of reciprocal complexity. This point of view is, however, so familiar, that nothing need be said in its further elucidation. The behaviour of any given animal does not stand alone, but is closely related with the behaviour of others. Among social animals the relationships are peculiarly close, and it is among them that the psychological aspect of behaviour reaches its highest expression.

IV.--CONTINUITY IN EVOLUTION

Under the head of organic behaviour, in the widest acceptation of the term, fall the whole of physiology, the whole of embryological development, nay, more, the whole of organic evolution; while mental evolution, in all its stages, may be regarded as the psychological aspect of that which, from the physiological aspect, is the evolution of nervous systems. Life itself is the behaviour of a particular kind of substance which is found more or less abundantly under natural conditions. No other known substance behaves in this way, and so ignorant are we as to the conditions of its natural origin, that it is useless to guess at a scientific explanation. And even if we knew all the antecedents and conditions of its origin we should be no nearer a comprehension of why protoplasm has the peculiar properties which we find it to possess. That is a question to which science can give no answer. Who knows why a certain compound of oxygen and hydrogen in certain proportions has the properties of that which we call water?

Let us note the distinction between saying, as we said above, that life is the behaviour of protoplasm, and asserting that life is the cause of this behaviour. The one is a scientific statement of observed fact, the other an explanation of the fact in metaphysical terms, a reference of the fact to its underlying cause. So long as we quite clearly understand that we are talking the language of metaphysics, we may speak of life as a cause of organic behaviour; but let us be careful to remember that the statement has no more value for science than the assertion that aqueosity is the cause of the behaviour of water.

Leaving on one side, then, the natural origin of protoplasm, the conditions of which are unknown, we find that, as a matter of observation, every bit of living substance, the history of which has been traced, is a fragment detached from some other bit which behaved in the same way. This is the basal fact of the continuity of organic evolution. But such a detached fragment has the property of increasing by taking up from the environment more of those elementary materials from which it is itself compounded in subtle synthesis. Nay, further, every fragment of which we know the history is found to increase in such a way as to reach, in form, structure, and idiosyncracies of behaviour, the likeness of the organism--plant or animal--from which it was derived. In the higher plants and animals the separated fragments or cells are the ova and sperms, or their equivalents, which unite, with fusion or coalescence of their nuclear matter, and thus give rise to a new individual in the course of embryological development.

Now, as we have already seen, much modern biological discussion centres round the question whether the detached reproductive fragment, ovum or sperm as the case may be, is derived from the whole body of the parent, by what Darwin termed pangenesis or in some other way, or only from germinal substance set apart in development for this end. And we have provisionally accepted the hypothesis that it is the direct descendant of other reproductive cells; and that, throughout a long ancestry, stretching back into the far past, there never occurs in the direct line of genealogical sequence, any highly differentiated cell, such as a gland-cell, muscle-cell, nerve-cell; never, with certain reservations into which we need not enter, is found the representative of any tissue save that to which the reproductive function is restricted. In technical phraseology, the continuity of organic evolution is due to the continuity of the germinal substance.

During embryological development the fertilized ovum--consisting of two fused fragments of this germinal substance--gives rise to a host of ordered and marshalled cells, which are divisible into two groups: the one forms the body with its muscles, bones, glands, digestive system, skin, sense-organs, nerve-centres, and so forth; the other forms a reserve store of germinal substance, from which are derived the ova and sperms. The former take no direct share in reproduction; they are off the line of continuous descent; they die without issue. But they protect and minister to the reproductive function of the second group--the potential ancestors of the races to follow. But all instinctive and intelligent behaviour is the outcome of the orderly working of the nervous system, is initiated through sensory stimulation, and is executed by the motor organs; and all the structural parts, through which such behaviour is possible, belong to the body--that which dies without issue. How, then, can instinct and intelligence be inherited? In a sense they are not inherited. The nervous system which is their organic basis begets no heirs. But it is begotten of germinal substance, which not only produced the body of which the nervous system is a part, but also handed on, with that body, samples of the same germinal substance capable of reproducing a similar body and a like nervous system. Herein lies the basis of heredity.

The stress of the struggle for existence falls upon the body; and instinctive or intelligent behaviour is a means to its preservation in the struggle for existence. According as it survives or not, will the samples of germinal substance it contains fulfil their biological end or perish with it. Natural selection secures the survival of those animals which bear the seed from which their like will be developed.

On this view all variation arises within the germinal substance, but it is manifested in the body which is its product. How variations arise we do not know with any exactness of detail. That the germinal substance is influenced in its nutrition and in other ways by the surrounding tissues is highly probable; and this influence may lead to changes which are the source of variations; but it is very doubtful whether such influence can be what we before termed “homœopathic.”[202] It is improbable that the formation of the nerve-connections involved in intelligent behaviour which has grown habitual through repetition, can so influence the germinal cells as to give rise to variations of like nature. In other words, acquired habit is probably not a direct determinant of an inherited variation of like nature in instinctive behaviour. Apart from such influence the only source of variations which can be assigned is either the differential division of nuclei in preparation for the process of fertilization,[203] or the process of fertilization itself. The union of perhaps differentiated germinal substance from two distinct parents affords the opportunities for the admixture and compounding of hereditary qualities in the two samples, from which variations favourable or the reverse may arise.

It is now generally recognized, however, that the origin of variations is a problem quite distinct from that of the survival of those whose direction is favourable to that end. The theory of natural selection, as such, does not pretend to offer any explanation of the manner in which variations arise; though of course a complete theory of organic evolution must assign the antecedents and conditions of organic progress in all its varied phases. We know that variations do occur; we know, too, that more individuals are born than survive to procreate their kind; and, on the theory of natural selection, we draw from these data the conclusion that, on the average, the animals that escape elimination are those in which the variations are of such a nature as to conduce to this end.

It will be seen that, on the hypothesis of organic heredity, thus briefly sketched, continuity can, in strictness and, as we may phrase it, in its first intent, only be predicated of the germinal substance; but that this substance gives rise to products--active vigorous animals behaving in certain ways, each after his kind--which hold similar germinal substance in trust for future use. Natural selection deals with the trustees; and if they succumb, that which they hold in trust is lost. To put the matter in another way: Nature says to the germinal substance, “By your products you must be judged in accordance with the criterion of utility and efficiency.” Practical use in the give and take of active life is the touchstone of all behaviour which makes for survival. This being secured, there may be a balance of behaviour for other purposes. But in animals the balance is not of large amount, and other purposes have not taken form and direction. It should be clearly noticed that, on the hypothesis we are considering, use is the test of survival, and though it is not the direct cause of variations, it affords their sanction in survival. That animal escapes elimination whose behaviour is of practical use; and it holds in trust for the future a store of germinal substance from which is produced a successor capable of behaving in like manner.

The whole drama of organic evolution may be regarded as the realization in a succession of individuals of the evolving potentiality of continuous lines of germinal substance. The successive individuals die--but the germinal substance lives on in their heirs, if they have any. In virtue of what intimate and hidden structure or disposition of parts the germ possesses this potentiality we do not know. The ovum of a dog is a microscopic speck less than one-hundredth of an inch in diameter; the sperm is far more minute. They unite, and their nuclei coalesce. The cellular product divides and subdivides. The cell colony absorbs nutriment from the maternal tissues. Division proceeds apace, and the cells are marshalled and ordered in embryological development; definite tissues are formed; the stages of their genesis can be predicted with accuracy; and in due time a puppy is born which shall grow to the likeness of its parents and behave as they behaved. We can trace the succession of events; we see that they form a related series; we have good reason for believing that the state of matters at any one moment is the antecedent condition of the state of matters at the succeeding moment. More than this science cannot say. The underlying cause is, for science, hidden in the mists of the unknown. Even for metaphysics it is but part of the force that beats through the universe and makes it not a chaos but a cosmos--a force known to us only in its effects.

It will thus be seen that the conception of continuity in organic evolution has, broadly considered, a threefold aspect. First, there is the continuity of the germinal substance through whose reproductive behaviour under the appropriate conditions embryological development occurs; secondly, there is continuity in this embryological development, stage by stage, from the fertilized ovum to the adult which is its final product and expression; thirdly, there is continuity in these final products, in the animals whose organic, instinctive, and intelligent behaviour lie open to our study and investigation. The first is germinal, the second developmental, the third evolutional continuity.

Before attempting to summarize some of the contributions afforded by our inquiry towards the doctrine of continuity in the last of these three aspects, we must pause for a moment to consider how far and in what sense continuity can be predicated of mental development.

We have regarded the conscious situation as the psychical aspect of a nerve-situation in the sensorium; and the nervous system, capable of behaving in this way, is in developmental continuity with the germinal substance of the fertilized ovum. But what shall we say with regard to the psychical aspect? Two hypotheses seem open to us, each of which presents difficulties, but of different kinds. The first is, that when the organic development of the nervous system reaches a certain level and order of complexity consciousness emerges, how and whence we know not. The second is, that consciousness is developed from sentience, which is the concomitant of all organic behaviour; which accompanies life wherever it occurs and therefore shares the continuity of the germinal substance.

The difficulty inseparable from the first hypothesis, is that it is contrary to the analogy of all that we know or infer elsewhere throughout the realm of nature. Huxley[204] likened its emergence to the production of heat when an iron bar is struck by repeated blows of the hammer. But this analogy will not hold; for heat is a mode of energy, and only emerges through the transformation of other and pre-existing modes of energy. A certain amount of the energy of motion in the massive hammer-head is transferred to the iron rod, and assumes the form of that molecular vibration which we call heat. And by what amount the one is the gainer, by that amount is the other the loser. But we have no reason to suppose that the like takes place in the origin of the mental concomitants of neural changes. No portion of the brain’s store of physical energy is drained off to form the rivulet of consciousness. Now, whenever we speak of a product elsewhere in nature, we mean a specialized bit of something pre-existent. Water is the product of pre-existing oxygen and hydrogen. Heat is the product of other forms of energy. But this is not so on the first hypothesis, according to which consciousness emerges when the functional activity of the nervous system reaches a certain level and order of complexity. The mental concomitants are not “products,” in the recognized sense of the term. Furthermore, although on this hypothesis we may still speak of what was termed above evolutional continuity in the mental concomitants, there is nothing analogous to either developmental or germinal continuity.

On the second hypothesis, according to which sentience is the concomitant of all organic behaviour, such developmental and germinal continuity, or their analogues in the psychical order of being, are rendered conceivable. Consciousness is regarded as a developed form of sentience. But the sentience is wholly hypothetical. It is at best a “may be,” and its existence is incapable of proof. And science is rightly impatient of hypotheses the validity of which cannot in any way be verified. Our safest course, therefore, is to accept that which is common to both hypotheses, evolutional continuity, and for the rest to be content with a confession of ignorance.

We have already drawn attention to the fact that mere sentience, if it exists, has no power of guidance over organic behaviour; but consciousness, when it emerges, is a concomitant of nervous processes which determine the nature and direction of such nerve-changes as are the antecedents of intelligent behaviour. The steps by which this control is established are unknown. It is, indeed, probable that conscious guidance arises as an accompaniment of the differentiation of controlling centres from the automatic centres of the nervous system; but of how this takes place we are as ignorant as we are of many other differentiations in the course of embryological development and evolutional progress. Of those nervous arrangements within the brain which are the physiological concomitants of the far later mental processes of reflection, abstraction, generalization, and the formation of ideals, we are, if it be possible, even yet more profoundly ignorant. Nor would it serve any good purpose to indulge in speculation where there are not even the data to enable us so much as to hazard a probable guess. The utmost we are justified in attempting is to show how organic behaviour leads up to and affords the requisite data for the exercise of intelligence, and how both supply the necessary preliminary stages in the development and evolution of what, following Dr. Stout, we have termed ideational process. This we have endeavoured to do in preceding pages; and all that is now required is to conclude our inquiry with a brief summary by which the results, as affording some basis for evolutional continuity, may be focussed.

We regard reflex action and instinctive behaviour, broadly considered, as genetically prior to that which is intelligent. Their development in the individual and their evolution in the race are reached by the differentiation and integration of nerve-centres. In the abdominal region of the crayfish, for example, special centres are differentiated for the behaviour of each pair of swimmerets; but these are so integrated that the whole series of like abdominal appendages swing rhythmically with co-ordinated movements. Now, when a sensorium is developed, it does not have to group by an act of conscious selection and deliberate arrangement the multiplicity of scattered sensory data which it receives; it does not have to organize from diverse and hitherto unrelated elements some sort of system in experience: it receives them as a physiological heritage already grouped, and to some extent organized. Stimulus and response are organically linked; and within the response inherited co-ordinations, often exceedingly complex, afford a correlated group of sensory data. Just in so far as organic heredity has provided a working system of bodily parts, does consciousness receive systematic information of their orderly working. No doubt it is true that the development and evolution of the sensorium proceeds _pari passu_ with the development and evolution of reflex actions compounded and co-ordinated to give rise to instinctive behaviour. No doubt the progress of the one is in close touch and relation with the progress of the other; for such relation receives the emphatic sanction of utility. Still it is none the less true that in individual development, as in racial evolution, the organic takes the lead. What is intelligently acquired is something added to that which has been engrained, through natural selection or otherwise, as a potentiality of the germinal substance. What we have first to note, then, is that organic evolution provides ready-grouped data to consciousness.

The second point is, that the germs of abstraction and generalization, or rather processes which are the precursors of abstraction and generalization, arise, and cannot fail to arise, in the genesis of experience from the performance of inherited responses, and from the coalescence of their results into a conscious situation. To a quite young chick I gave pieces of yellow orange peel, which were found to be distasteful and rejected. In Dr. Stout’s phraseology, they acquired meaning in experience. Can one doubt that the colour and taste were thus rendered predominant, and that the shape, size, and other qualities of the bits of orange peel remained practically unnoticed? Shortly afterwards the chick was given chopped and crumbled egg; the fragments of “white” were eaten, but the bits of hard-boiled yolk were untouched. They possessed a sufficient general resemblance to the orange peel to carry the same meaning. In many ways particular qualities of objects are emphasized in so far as they incite to behaviour; they form centres of biological interest, just as the abstract quality of ideational thought is the centre of rational interest on a higher plane of mental development. And in many ways objects presenting certain salient features in common, amid differences which remain unnoticed, are unconsciously grouped as the starting-points of similar perceptual situations, just as in the generalization of ideational thought similar relationships are deliberately grouped as the starting-points of like conceptual situations. Both are purposive and have an end, which we as investigators are able to assign; but only for reflection and conceptual thought are they also purposeful--the end being foreseen and realized, not only by the investigators, but by the agent concerned. And the purpose or end itself is in the two cases different. In the one case it is the biological end of practical behaviour; in the other case it is the rational end of explanation--abstraction and generalization being deliberately used as a means to this latter end. The question has again and again been asked: Do animals reason? And different answers are given by those who are substantially in agreement as to the facts and their interpretation, but are not in agreement as to their use of the word “reason.” Perhaps, if the question assume the form--Are animals capable of explaining their own acts and the causes of phenomena?--the position of those who find the evidence of their doing so insufficient may be placed in a clearer light. This is what is generally meant by the statement that animals have probably not reached the level of rational beings.

But even if they have not reached this level, their perceptual processes supply the antecedent conditions which are necessary if this level is to be attained in the course of further evolution. We have seen that, even in relatively simple cases, where conscious situations mark only the beginnings of intelligence, there is a biological emphasis of some, rather than others, among what we call the qualities of objects, and there is a grouping, on biological grounds, of certain things which have some quality in common--such, for example, as being fit for food. Here we have at the outset of perceptual development the germs of processes which are the precursors of the abstraction and generalization of ideational thought. And in the more complex conscious situations of the higher animals these processes attain to such degree of development as is necessary to secure more difficult and more remote biological ends, until all that is necessary, for their rational use, is the quickening touch of a new purpose, that of explanation.

We have seen that, through what Dr. Stout terms “manipulation,” and Professor Groos “experimentation”--names applied to a type of behaviour widely exemplified among the higher animals,--things, as the nuclei of conscious situations, become differentiated from the environment. One can hardly question that a fly to the trout, a ball to the kitten, a bone to the puppy are things distinguished from their surroundings, and that they become marked off as special centres of interest. Here on the perceptual plane is a process which is the antecedent of the conception of quasi-independent objects on the ideational plane. For rational thought the thing, as object, is not only the centre of a practical situation leading to behaviour of direct or indirect biological value, but is the nucleus around which we build all the qualities which are ascertained by more elaborate manipulation and experimentation carried out deliberately and of set purpose for rational ends. It becomes capable of definition with the aim of explaining what are its characteristics as an object.

There can be little doubt that the higher animals become intimately and practically acquainted with their environment. The dog who accompanies his master in many a ramble, the horse who carries him again and again over all the surrounding country, has a good perceptual knowledge of a somewhat extended environment. And this, again, is the precursor of the far more extended conceptual knowledge which leads up at last to a rational conception of the universe of objects in their varied relationships. But only through the concentration of thought rendered possible by much true abstraction and generalization,--only through disentangling the relationships and regrouping them for the purpose of framing an ideal scheme,--only, in short, by explanation and for the sake of explanation is this difficult process brought to a more or less successful issue.

Again, there can be little doubt that the higher animals, in the course of experience begotten of behaviour, reach a perceptual sensing of the bodily self, through experience derived from the non-projecting senses, in pain and sickness, and often, we may hope, in the sense of well-being, and the joy of existence. They do not probably set this self in antithesis to the not-self. That comes with reflection, and is the result of ideal construction based on the analysis of experience, with a view to reaching some explanation of the genesis of experience. But in their perceptual awareness of the embodied self, they have that kind of consciousness which affords the necessary data, for the later conception of the self--when experience is polarized into its subjective and objective aspects and thus is explained, so far as science can explain it; suggesting, indeed, long ere science has attained this end, metaphysical explanations by reference to underlying causes--too often accepted as an easy substitute for the difficult tracing out of the antecedent conditions which science endeavours painfully and by slow steps to formulate.

It is unnecessary to do more than remind the reader that we have found that such processes as attention and imitation pass through instinctive and intelligent stages which are the precursors of the ideational stage, where they reach a higher expression as deliberately conscious acts. In the young bird that instinctively pecks at some small, perhaps moving, thing, which forms the starting point of a piece of responsive behaviour, we have attention in the germ. When experience has caused the thing to acquire meaning, attention passes into a succeeding intelligent phase; but only when we desire to explain this meaning, and attention thus has a deliberate purpose, do we find it entering upon its higher ideational career. So, too, as we have seen, imitation is at first a specialized form of instinctive behaviour, where the response is seen to resemble that which stimulates it. Later it becomes intelligent when the repetition of the imitative behaviour is due to the satisfaction it introduces into the conscious situation. Then, at last, it reaches the ideational stage, where reflection gives rise to an ideal, which is to be realized in conduct. The imitation by the child of its older companions is at first probably intelligent; but when the child begins to consider why it imitates these and not those among its companions, he is passing to the ideal stage, and imitation becomes the sincerest form of hero-worship. The boy who merely imitates his elder brothers playing at soldiers because he gets satisfaction from so doing, becomes the subaltern who has his ideal soldier, and will face death firmly rather than fall below his conception of how such a soldier should behave.

We need not again attempt to indicate how among animals we have the perceptual precursors of the æsthetic and ethical concepts. But we may remind the reader that we endeavoured to show that intercommunication had its foundation in instinctive sounds; and that it passed into the intelligent stage in the perceptual life, when these sounds acquired meaning, and hence became guides to behaviour. This is especially instructive from our present standpoint, since it is probable that the passage of communication from the indicating to the descriptive stage afforded the conditions under which rational thought was evolved. For such thought it is essential that attention should be focussed on the relationships of things. And no description is possible without making distinctly present to consciousness these relationships, in time and space, the data for which are abundantly present in the perceptual life, though lurking in the background, and needing something to fix them and to aid consciousness in distinguishing them clearly. In descriptive communication parts of speech, or their initial equivalents, afford fixation points for these relationships, and serve to render them distinct. If the reader will try to describe even the simplest occurrence without introducing the symbols for the relations which the events bear to each other, his failure will serve to bring home how essential a feature this is. In social communication, then, we probably have the key to the passage from perceptual to ideational process; and in this passage description is the antecedent of, and affords the conditions to, explanation. Words, moreover, as we have already said, form the pegs upon which we can hang up, for ready reference, the products of abstraction and generalization, or, to modify the analogy, they form the bodies of which these products are the rational soul.

If we are ever to trace the passage from the instinctive through the indicating stage of communication, and so onwards through the beginnings of description to its higher levels, and thus to the use of language as a medium of explanation, it must be through child-study. In every normal human child the passage does actually take place, though, no doubt, in a condensed and abbreviated form as an epitomized recapitulation in individual development, of the steps of evolutional progress. Thus we may obtain a key to the solution of one of the most difficult problems in evolution by continuous process--that of the transition from animal behaviour to human conduct.

INDEX

A

Abstract and general ideas, 57

Abstraction, 166;
germs of, 332 ff.

Acceleration, 250

Accommodation defined, 36

Acquired characters, inheritance of, 35, 110

Acquired instincts (Wundt), 66, 106

Acquisition defined, 36;
ultimately dependent on natural selection, 289

Adaptation defined, 37

ADDISON on instinct, 63

Æsthetics, animal, 270

Afferent and efferent impulses, 32, 101

Aid, mutual, among animals, 227

_Ammophila_ mode of stinging prey, 75;
of carrying prey, 76;
deposition of egg, 77;
intelligent behaviour of, 127

_Amœba_, 296

Antlers of deer, 15

Ants, behaviour of, 123;
intercommunication of, 198;
social communities of, 205

_Aporus_, intelligent behaviour of, 126

Appreciation, germs of, 273

Ardour of male in courtship, 269

_Argyromœba_, instincts of, 79

Arrest of development in egg, 14

Association in coalescent situation, 46

Attention, 242

AUDUBON on American night-hawks, 261

AVEBURY, Lord, on ants, 198;
on Van, 200;
on aphides and ants, 214;
on slave ants, 215;
on intelligence of ants, 218

B

BALDWIN, Prof. Mark, on organic selection, 37 (note), 115;
on functional selection, 163;
on imitation, 179 ff.;
on projective stage of development, 275

Batesian mimicry, 165

BECHSTEIN on canaries, 262

Bees, homing of, 131;
social communities of, 205

Beetle soliciting food from ant, 213

_Bembex_ mode of carrying prey, 76

BETHE, Dr., on instinctive behaviour of ants, 217

BINET, M., on infusoria, 6

Biological value of play, 250;
purpose, 294;
aspect of animal behaviour, 305

Birch-weevil, leaf-case of, 121

Birds, instinct of, 84

Bison, behaviour of the, 226

BLACKBURN, Mrs. Hugh, on instinct of cuckoo, 90

BLOCKMANN, Dr., on _componotus_, 210

BOLTON on goldfinches’ nests, 136

Bower-bird, observations on, 261, 273

BUCKMAN, Mr. S. S., on speech of children, 203

BUDGETT, Mr. John S., on nest-building, 135

Bullfinch, nest of, 135

C

CAMERON, Mr., on mimetic insects in ants’ nest, 212

Canaries’ nest, building of, 135

Canon of interpretation, 270

Capacity, innate, 176

Capuchin monkey, imitation in, 188, 278

CARPENTER, W. B., on water-beetle, 299

Catasetum, fertilization of, 29

Cats, Prof. Thorndike’s experiments on, 147, 184

Causation, idea of, 257

Cell-division in egg, 14

_Cerceris_, instincts of, 74;
locality studies of, 129

_Chalicodoma_, parasites of, 78;
Fabre’s observations on, 130

Chick swimming, 85;
instincts of, 85 ff.;
imitation in, 183

Child-study, desirability of, 155, 337

Choice, apparent in Paramecia, 9;
in the pairing situation, 266

Ciliary action in Paramecium, 4-10

Circular process (Baldwin), 181

_Clepsine_, behaviour of, 159

Coalescence in conscious situation, 46

Coincident variations defined, 37;
survival of, 115, 174

Communities, social, of bees and ants, 205

Companion as centre of special interest, 244

_Componotus_, communities of, 210

Conation and impulse, 187, 235

Concept, nature of, 167

Condensation of experience, 163

Conduct implies motive, 60;
and ideal, 278

Congenital responses, 41

Conjugation in Paramecium, 4

Connate instincts, 66, 69

Conscience, ambiguity of word, 281

Conscious accompaniments of certain organic changes, 42;
aspect of instructive behaviour, 99

Consciousness, as accompaniment and as guide, 34;
effective, defined, 43;
as heir to organic estate, 52;
as epiphenomenon, 306

Consentience, 53, 62

Consonance of biological and psychological end, 286, 316

Constancy of environment leads to stereotyped behaviour, 173

Continuity in evolution, 324;
threefold aspect of, 329

Control, the sign of effective consciousness, 43

Co-ordinated acts, 69, 100;
inherited, 94, 95

Corporate behaviour, 14

Courtship in animals, 259

Coyness of female birds, 264 ff.

Cranial sense-organs, 301

Crayfish, reflex action in, 298

Creation, special, 297

Criteria of effective consciousness, 43;
of intelligence, 120

Cruelty in cat, 277

Cuckoo, instinct of nestling, 90

D

DARWIN, Charles, fig. of sun-dew leaf, 26;
of Venus’s fly-trap, 27;
of catasetum, 31;
on earthworms, 158;
on social life of animals, 225;
on human ancestry, 229;
on play and practise, 259;
on sexual selection, 262 ff.;
on law of battle, 313

DAVIS, Prof. Ainsworth, on limpets, 156

DEAN, Dr. Bashford, on chick swimming, 85

Deceit in animals, 280

Deferred instincts, 70

Definiteness of instinctive behaviour, 66

Description, involves relational terms, 202

_Didunculus_, changed habits in, 221

Differentiation and integration of nerve-centres, 167

Disintegration of instincts, 176

Diving, instinctive, 86

Dog, observations on, intelligence of, 141 ff., 152, 200, 271, 322

Duckling, inherited co-ordination in, 96

_Dytiscus_, instinct of, 104

E

Earthworms, Darwin’s observations on, 158 ff.

Education in play, 255, 320 ff.

Effective consciousness defined, 43

Efferent and afferent impulses, 32, 101

Egg, cell-division in, 14

EIMER, Th., on instincts of solitary wasps, 73;
on origin of instincts, 108

Emotions, and feelings, 235 ff.;
psychological nature of, 246;
evolution of, 282

Energy stored in cell, 23

Equilibrium, tendency to, 296

_Eristalis_, mimicry of, 164

ESPINAS, Prof., on social life of animals, 230

Ethics, animal, 270

Evolution of organic behaviour, 35;
of consciousness, 61;
of instinctive behaviour, 106;
of intelligent behaviour, 155;
of social behaviour, 225;
of feeling and emotion, 282;
of animal behaviour, 295;
as continuous, 324 ff.

Experience, of value for future guidance, 44;
is it inherited? 48, 97;
condensation of, 163

Experimentation, 251, 253

Explanation, characteristic of later phases of mental development,
58, 257

Explosive nature of cell, 21

Expression of emotions, 247

External stimuli to instinctive behaviour, 102

F

FABRE on behaviour of _Sphex_, 77, 172;
of _Chalicodoma_, 78, 129;
of _Leucopsis_, 79;
of _Pompilus_, 129

Faculty, instinctive, 64

Falcons, training of, 137

Fear in birds not inherited in specific direction, 49, 110

Feelings and emotion, 235 ff.;
evolution of, 282;
feeling-tone, 240

Ferns, fertilization of, 24

Fertilization of ferns, 24;
of _Valisneria_, 28;
of orchids, 29

FINN, Mr. Frank, on the acquisition of experience by young birds, 50

Fission, reproduction of Paramecium by, 4

Flight, instinctive, 86

FOREL on _Componotus_, 211

FOSTER, Sir Michael, on consciousness accompanying reflex action in
pithed frog, 33

Frog, reflex action in, 33, 299, 300

Functional selection, 163

Fungus garden of ants, 216

G

GARNER, Mr. R. L., “The Speech of Monkeys,” 198

Gas-engine, analogy of, 20

General and abstract ideas, 57;
generalization, 167;
germs of, 332 ff.

Generic image, 162;
situations, 163

Germinal substance, continuity of, 328

GOULD, Dr., on humming-birds, 273

GREEN, Mr. E. G., on ants, 210

Greenfinch, nest of, 135

GROOS, Prof., on instinct, 64;
origin of, 116;
on imitation, 187;
on animal play, 248 ff.;
on “Love Play,” 259;
on coyness of female birds, 264;
on choice in mating, 267;
on make-believe, 280

H

Habits and habitual acts, 107, 177

HAGUE on ants, 199

HAMERTON, P. G., on trained dog, 152

HANCOCK, Dr. John, on cuckoo, 92

Heredity and circumstance, 39;
twofold aspect of, 40;
relation of to use, 170, 177;
in evolution as continuous, 326

Homing of bees, 131

Homœopathic influence defined, 36

Honey-pot ant, 215

House-martin, nest-building of, 113

HUDSON, Mr. W. H., on fear in birds, 49, 50, 110;
on animal gladness, 317

Hunting play, 254

HUXLEY, T. H., on reflex action in frog, 300;
on consciousness as epiphenomenon, 306 ff.;
on consciousness as product of nervous changes, 330

HYDE, Mr., on king-crab, 298

_Hydractinia_, colonial polype, 206

I

Ideals, distinguish ethics, 278

Ideational stage of mental development, 59

Imitation, 179 ff.;
three stages of in child, 192

Impulse in intelligent behaviour, 60;
Prof. Thorndike’s use of the term, 186;
connection of with conative process, 235

Independence of automatic and controlling centres, 43

Infant, congenital responses in, 54

Influence of intelligence on instinct, 169

Inheritance of acquisitiveness, 40

Innate capacity, 176;
likes and dislikes, 119

Insects, instinctive behaviour in, 71;
intelligent behaviour in, 123

Instinct, broader and narrower view of, 99;
primary and secondary, 108, 109;
influence of intelligence on, 169;
priority of, to intelligence, 173;
disintegration of, 175

Instinctive behaviour defined, 63;
in insects, 71;
in birds, 84;
conscious aspect of, 98

Integration and differentiation of nerve-centres, 167

Intelligence lapsed, 107;
influence of, on instinct, 169;
of ants, Lord Avebury on, 218;
biological importance of, 310

Intelligent behaviour, 117;
evolution of, 155

Intelligent process distinguished from rational, 59, 138

Intercommunication, 193, 336

Interest, 243

Internal factors in instinctive behaviour, 102

Irritability, fundamental, property of protoplasm, 240, 296

J

JAMES, Prof. Wm., theory of emotions, 246, 292

Jays, bathing of, 89;
mode of taking food, 94

JENNER on cuckoo, 92

JENNINGS, Dr. H. S., on behaviour of Paramecia, 5

K

KERNER, Dr., on sun-dew, 26;
on sensitive Oxalis, 27;
on Valisneria, 29

King-crab, reflex action in, 298

KNIGHT, Andrew, on Norwegian ponies, 110

KROPOTKINE, Prince, on mutual aid among animals, 227

L

Lamarckian hypothesis, 169, 171, 177

Language, nature of, 195

LANKESTER, Prof. E. Ray, on small-brained mammal, 168

Lapwing, instinctive behaviour of, 113

Law of battle, 313

Leech, observation on, 159

_Leucopsis_, instincts of, 79

LEWES, G. H., on lapsed intelligence, 107

Limpets, observations on, 156

LINDLEY, Dr., on children, 141

Locality, studies by wasps, 128

LOCKE, John, limitations of animals, 167

M

MACKENZIE, Prof. J. S., on ethics, 278;
on conscience, 281;
on ambiguity of word “pleasure,” 285

Make-believe, 280

Mammals, early small-brained, 168

Manipulation (Stout), 251

MARCHAL, Prof., on instincts of _Cerceris_, 74

MARSHALL, Mr. H. R., on instinct, 66

Martin, nest-building of, 113

MARTINEAU, James, on pleasure and pain, 284

MAUPAS, M., observations on infusoria, 4

MAYER, Dr. A. G., on mating instinct of moths, 83

MCCOOK, Dr., on ants, 214

Meaning, Dr. Stout’s use of term, 46, 243, 268

MEDLICOTT, Mr. H. B., on behaviour of wild pigs, 196

Megapodes, instinctive flight of, 87

_Meloë_, instincts of, 81

Mental development, stages of, 48, 56

MERCIER, Dr. Charles, on criteria of intelligence, 120

Metaphysical explanations, 19;
aspect of instinct, 64;
of impulse, 237;
of purpose, 294;
of will, 307;
of life, 325

MILLS, Prof. Wesley, on social influence on puppy, 220

_Miltogramma_, parasitic fly, 134

Mimicry, Batesian and Müllerian, 165;
intelligent aspect of, 311

Modifiability, 171

Modification, defined, 36;
relation of, to hereditary characters, 170

MÖLLER, Herr, on fungus garden of ants, 216

Monistic hypothesis, 309, 315

Monkey, capuchin, imitation in, 188

_Monodontomerus_, instincts of, 79

Moor-hen, diving of, 89

Moths mating, instinct of, 83

Motive in rational conduct, 60

Movement plays, 251

MÜLLER, Prof. Max, on barrier between brute and man, 204

Müllerian mimicry, 165, 166

Mystery of life, 18

N

Natural selection, shielding of chicks from, 111;
under uniform and variable circumstances, 175;
in playtime of life, 319

Nervous arc, 33;
system of higher animals, 297

Nest-building, observations on, 135

NOIRÉ on concept, 167

Norwegian ponies, 109

Nucleus division, 12

O

Object and subject, 245, 276

Octopus, intelligence of, 158

_Œcophylla_, behaviour of, 210

Orchids, fertilization of, 29

Organic basis of differentiation of consciousness, 53

Organic behaviour in development, 15

Organic selection, 37 (note), 115

Overproduction of movements, 164

Oxalis, sensitive, behaviour of, 27

_Oxybelus_, mode of carrying prey, 76

P

PALEY, definition of instinct, 64

Paramecium, behaviour of, 3, 296

Partridge, note of young, 93

PECKHAM, Dr. G. W., on instinct, 65;
on solitary wasps, 72 ff., 126 ff.

Pecking instinct of chicks, 93

Peewit, note of young, 93

_Pelopœus_, instincts of, 72

Perceptual stage of mental development, 59

Personality, 245, 257

Pheasants, note of young, 92;
inherited co-ordination in, 95;
plumage of Argus, 262

_Philanthus_, prey of, 73;
mode of stinging prey, 74

Physiological aspect of animal behaviour, 295

Pigeons, nests of, 136

Pigs, wild, behaviour of, 196

Plants, behaviour of, 24

Plastic period of life, 168

Plasticity of tissues, 40;
of behaviour, 172

Play of animals, 248 ff.;
biological value of, 250;
psychological aspect of, 256, 311, 316

PLAYNE, Mr. H. C., on pigeons’ nests, 136

Pleasure, 241;
ambiguity in word, 285

_Polistes_, locality studies of, 131

_Pompilus_, mode of carrying prey, 76;
Fabre’s observation on, 129

Presentative elements distinguished from re-presentative, 46

Primary instincts (Romanes), 108

Projective stage of mental development, 275;
senses, 304

_Pronuba_, instinct of, 82

Propensity, instincts as, 64;
congenital, 176

Protoplasm, fundamental properties of, 296

Psychological aspect of play, 256;
purpose, 294;
aspect of animal behaviour, 315

R

Rational process distinguished from intelligent, 59, 138

Reflex action, 31, 35, 298 ff.;
relation of instinct to, 70

Relationships, importance of, 202

Re-presentative elements distinguished from presentative, 46

_Rhynchites_, instinct of, 121

ROMANES, G. J., on “discrimination” and “perception” in plants, 32;
on instincts of solitary wasps, 73;
definition of instinct, 99;
on primary and secondary instincts, 108, 109;
on ants, 126;
on general ideas, 166;
on animal communication, 201;
on cruelty in cat, 277

ROMANES, Miss, observations on capuchin monkey, 188, 278

Roots of spinal nerves, 299

ROTHNEY, Mr. G. A. G., on Indian ants, 212

S

SCHNEIDER, on octopus, 158

SCOTT, Dr. D. H., on fern fertilization, 25

Scratching in duckling, 96

Sea anemone, diffused nervous system of, 32

Secondary instincts (Romanes), 108, 109

Segmental nature of central nervous system, 299

Selection, functional, 163;
natural, shielding of chicks from, 111;
under uniform and variable circumstances, 175;
in playtime of life, 319;
sexual, 261 ff., 313

Self, as ideal construction, 239

Sentience, 62;
origin of, 330

Sexual selection, 261 ff., 313

SHARP, Dr. D., on birch-weevil, 121;
on _Œcophylla_, 210

SHELLARD, Mr. E. J., observations on staghound, 144

SHERRINGTON, Prof., on emotion, 292;
on spinal animal, 298 ff.

Shock, effects of physiological, 302

SIMCOX, Miss Edith, quoted, 320

_Sitaris_, instincts of, 82

Slave ants, 215

Snails, observations on, 157

Social behaviour, 179;
evolution of, 225

Solitary wasps, instincts of, 72 ff.;
intelligence of, 126 ff.

Solomon Islands, rats of, 222

Sounds emitted by young birds, 92

SPALDING, Douglas, on newly hatched turkeys, 49;
on instinct, 99

Special creation, 297

Speech, connection of, with rational process, 58, 233;
so-called, of monkeys, 198;
of children, 203;
aids passage from perceptual to ideational process, 337

SPENCE, on instinct, 63

SPENCER, Mr. Herbert, on instinct and reflex action, 70;
on play due to surplus vigour, 248;
on pleasure and pain, 284, 287;
on survival, 288

_Sphex_, mode of carrying prey to nest, 77, 172

Spiders placed in crotch by wasps, 133

Stereotyped behaviour, 172

Sticklebacks, observations on, 130

STOUT, Dr. G. F., on “meaning” for consciousness, 46, 243, 268;
on ideational and perceptual stages of mental development, 59, 271;
on octopus, 158;
on conative process, 235;
on the self, 239;
on manipulation, 251;
on emotion, 293

STRANGE, Mr., on bower-bird, 261

Subject and object, 245, 276

Sun-dew leaf, behaviour of, 25

Swimming, instinctive, 85

T

TAIT, Lawson, on begging-cat, 110

TARDE, M., on imitation as a social factor, 179

Tendencies, congenital, 176

THOMAS, Mr. Oldfield, on rats of Solomon Islands, 222

THORNDIKE, Dr., on swimming of chick, 85;
experiments on intelligence, 147 ff.;
experiments on imitation, 179, 183 ff.

Tradition, animal, 220

Trial and error, method of, 139

U

Unity of perceptual process, 240;
of biological purpose, 297

Use, super-normal, 170;
relation of, to heredity, 171, 177

V

VALISNERIA, fertilization of, 28

Variation defined, 36;
origin of, 327

Venus’s fly-trap, behaviour of, 26

Vigour, play due to surplus, 248

Volition as conative, 238

W

WALLACE, Dr. A. R., on sexual selection, 264

WALLASCHEK, Mr., on play as surplus vigour, 248

Wapiti, antlers of, 16

WASMANN, Dr., on insects associated with ants, 213

Wasps, solitary, instincts of, 72 ff.;
intelligence of, 126 ff.

WEIR, Mr. Jenner, on canaries, 135

WEISMANN, Prof., on origin of instinct, 109

WHITMAN, Prof., on _Clepsine_, 159

WHITMEE, Rev. S. J., on tooth-billed pigeon, 221

Will, metaphysics of, 307

WILLISTON, Dr. S. W., observation on _Ammophila_, 127

WOOD, Mr. Foster, on hen-swimming, 86

WORCESTER, Dr., on megapode, 87

WUNDT, Prof., on instinct, 65, 99, 106

Y

Youth, plasticity of, 168

Yucca moth, instincts of, 82

THE END

PRINTED BY WILLIAM CLOWES AND SONS, LIMITED, LONDON AND BECCLES

FOOTNOTES

[1] See “The Psychology of a Protozoon,” in the _Amer. Jour. of Psychology_, vol. X., No. 4, July, 1899, and the fuller papers there quoted.

[2] “The Psychic Life of Micro-Organisms,” 1889, p. 61.

[3] This paragraph is taken from “Animal Life and Intelligence,” p. 28.

[4] The following paragraphs are taken with some slight changes from “Animal Life and Intelligence,” pp. 30-35.

[5] D. H. Scott, “An Introduction to Structural Botany,” part ii., “Flowerless Plants,” pp. 70, 71.

[6] _Ibid._, p. 71.

[7] Kerner, “Natural History of Plants,” translated by F. W. Oliver, vol. i., p. 145.

[8] Kerner, “Natural History of Plants,” vol. i., p. 536.

[9] Kerner, “Natural History of Plants,” vol. ii., p. 132.

[10] Darwin, “Fertilization of Orchids,” 2nd edit., pp. 191, 192.

[11] “Mental Evolution in Animals,” p. 50.

[12] _Ibid._, p. 51.

[13] “A Text-book of Physiology,” 5th edit., part iii., p. 909.

[14] “A Text-book of Physiology,” 5th edit., part iii., pp. 911, 912.

[15] Professor Mark Baldwin has applied the term “organic selection” to the result of this interaction (_American Naturalist_ for June and July, 1896). Cf. also H. F. Osborn (_Science_, Nov. 27, 1896); August Weismann (Romanes Lecture on “The Effects of External Influences on Development,” 1894), and “Germinal Selection,” _Monist_, Jan., 1896; and the author’s “Habit and Instinct,” ch. xiv., 1896.

[16] “Habit and Instinct,” p. 26.

[17] _American Journal of Psychology_, vol. ix., No. 1.

[18] _Psychological Review_, vol. vi., No. 3.

[19] “Naturalist in La Plata,” p. 88.

[20] _Journal Asiatic Society of Bengal_, lxvii., part ii., 1897, p. 614.

[21] _Spectator_, No. 120.

[22] Kirby and Spence, “Introduction to Entomology,” Letter xxvii. p. 537 (7th Edit., 1858).

[23] Cf. supra, p. 18.

[24] “The Play of Animals,” translated by Elizabeth L. Baldwin, p. 62.

[25] George W. and Elizabeth G. Peckham, “On the Instincts and Habits of the Solitary Wasps,” p. 231.

[26] “Lectures on Human and Animal Psychology,” pp. 388, 397, 399.

[27] “Instinct and Reason,” pp. 90, 92.

[28] “Instinct and Reason,” p. 91.

[29] Chapter I., Section V.

[30] “On the Habits and Instincts of the Solitary Wasps,” by George W. and Elizabeth G. Peckham (1898).

[31] “Mental Evolution in Animals,” p. 299.

[32] “Organic Evolution,” translated by J. T. Cunningham, p. 280.

[33] See A. G. Mayer “On the Mating Instinct of Moths.” _Ann. and Mag. of Nat. Hist._, ser. 7, vol. v., Feb., 1900, p. 183.