From the above review of different manifestations of cultural adaptation, as they are reflected in the psycho-mental complex of ethnical groups, we can see that the complexes may be very distinct and that there is no absolute similarity of two complexes, although there may be common elements, which may give an idea of a common origin of the complexes. Naturally, the question comes to that of the formation of complexes. Although the observer may receive the impression of an incidental character of all complexes studied here, this impression will not be correct. First of all, the creators of complexes are themselves bearers of complexes who put together elements found in the milieu, so that every complex strictly depends on the historic moment at which it is created, and on the milieu from which bearers of the complex draw the elements. Secondly, there are great limitations as to the possibility of the incorporation of new elements into an existing complex. Thirdly, when no ready elements are found, they are invented; but the possibility of invention is limited by the fact of the smallness of the Tungus groups.
The first condition is evident from the observed facts. The Tungus who live in different ethnical milieus, even though being beyond the control of their neighbours, are liable to borrow distinct elements. For instance, the Reindeer Tungus of Transbaikalia, now living in contact with the Buriats, and formerly with the Yakuts, are found in a position different from that of the Birarchen Tungus who were in contact with the Goldi and Dahurs. Still greater is the influence of the groups which controlled the Tungus in the past or control them now, such as the Dahurs, Manchus, Chinese and Russians. When cultural influence is reinforced by political pressure, the alien milieu becomes a very intensive source of borrowing of elements, from which the Tungus draw whatever suits their complex. The same is true of the Tungus ethnical milieu from which it is still easier to borrow elements that are needed. As a matter of fact, no understanding of the Tungus complexes is possible without the consideration of the historic and present conditions of the ethnical milieu.
Limitations of borrowing depend, in the first place, on the existing complex of primary milieu. It is evident that the elements directly connected with agriculture, which is impossible in some Tungus regions, are automatically rejected. It should be noted, that sometimes also elements only indirectly connected with agriculture, but to some degree dependent upon it, as for instance, the agricultural calendar, spirits held responsible for the success of agriculture etc. may be rejected. The same is true of other cultural complexes which depend on the primary milieu. For instance, means of communication and modes of orientation and topographical terminology therewith connected, as well as the complex of technical adaptation may depend on the primary milieu. It is evident that in a locality where the cart cannot be used and where there is no food for horses the elements of the locomotion complex by means of horse-drawn vehicles and their reflection on the psychomental complex will not be borrowed
The conditions (structure) of the cultural complex may also be responsible for rejection. Although some technical inventions are very useful, they cannot be adapted and therefore they are rejected. For instance, the modern rifle is much «superior» to the flint or piston gun, but since he bullet is too large, this weapon cannot be used for hunting squirrels — the animal is too small and the cartridges are too expensive. Therefore guns of the oldest type, but of small calibre, are preserved as particularly precious. The Tungus sometimes manufacture such guns, the rough specimens of which produce on ethnographers an impression of «primitiveness». Indeed, although a rapid-shooting automatic rifle is superior to the common one-cartridge Berdan rifle, the latter will be preferred by the Tungus, because with a modern gun of small calibre big game, such as the Alces, the tiger and the bear often cannot be killed by one shot and, being wounded, may run away. A great number of elements which presume the existence of an extensive division of work, «class organization» etc. will not be borrowed, for the Tungus are not numerous and cannot afford to have specialists. The small number of the population in small ethnical groups greatly restricts the borrowing of new elements. In fact, it is very often forgotten that small ethnical units cannot assimilate some complexes at all because of the need of a certain number of population for the introduction of these complexes; and the failure of the ethnical units to assimilate alien complexes of this type is attributed to the inborn lack of mental and psychic ability. Owing to the limited population in the Northern Tungus groups the idea as to the social distinction of individuals, according to their economic position, is not accepted and, even being known, is greatly adapted and naturally distorted, as compared with the original models. There is of course a possibility of «learning» an alien complex and of teaching the Tungus, but these instructed Tungus would not be in a position to apply the learned elements to their own complex. Such a knowledge will be merely a «Tungus knowledge about other ethnical groups», which cannot be practically applied, and if there is a too great number of Tungus familiar with it, it will become a simple burden. The practical uselessness of the elements to the borrowers is generally a cause of rejection of alien elements. The elements which are not useful may be borrowed, but only in a limited number. This principle, though very simple, may sometimes be wrongly applied. In fact, the decision of rejection does not need to pass through the consciousness of the ethnical unit. In this case the mechanism is that of a trial. If the element does not bring any practical effect and if the unit is not particularly inclined to keep it, it will be dropped. However, if the unit wishes to keep it at any price, another mechanism, that of the loss of badly adjusted elements comes in play; the unit loses its adaptive ability and enters into a series of negative impulses of variations, or still more commonly, it is pressed by the neighbouring groups and the element perishes together with the unit. Certainly, a limited number of such elements may be preserved for a long time, sometimes at a high cost, but this cannot occur with a great number of elements. Among all Tungus groups we have observed the introduction of cultural elements which were tried during a certain period and rejected. Probably thousands of Tungus were attracted by the watch, but this instrument, very useful in city conditions, is practically a burden in the Tungus conditions, and is not given «recognition». However, water-proof and half water-proof canvas, e g. for tents, are greatly appreciated and when received from foreigners, they may be included into the Tungus complex, which one may observe among several groups. The same is true as regards the accumulation of knowledge. Although the high mathematics is a very useful method, in the conditions of Tungus life it is useless, like the theory of electricity, the history of the Greek philosophy etc. Should the Tungus spend their energy on this knowledge, they would lose their time needed for the training in hunting, shooting, migrating, and practical knowledge of the milieu. The process of elimination - i.e. rejection — of this knowledge is very simple. The individual Tungus who possess such a knowledge, useless for the Tungus, (1) will not be considered as worthy of imitation, (2) will come into a conflict with his Tungus milieu, and (3) will leave his people and settle among those from whom he learned the new elements. This is the most common occurrence among the Tungus, some cases of which I have already quoted (vide Chapter XXXI). The Tungus are naturally no exception -this is the most common occurrence which may sometimes cover even a social group that would be rejected on the first suitable occasion, which, in this case, would take the form of a «social movement» and under certain conditions even that of a «revolution» [713].
When the change of language is connected with the psychomental disrupture, the process of rejection may also assume a form of ethnical conflict (chiefly in «nations»). Owing to the action of this mechanism among the Tungus, useless elements of knowledge borrowed from the interethnical milieu are rather seldom met with. However, when we introduce the principle of utility, important corrections must be made. First of all, the utility may be weighed when expenditure and benefit are taken into account. There are elements which being useless, as such, require no expenditure for their maintenance, so their existence is not protested. For instance, we have seen some customs in the wedding ceremony which are not Tungus and have no visible practical importance, but which are maintained, because there must be some complex of custom to mark the fact of wedding, i.e. the obligations imposed by marriage. Sometimes the «utility» cannot be understood by the Tungus, and only our analysis of the function of the element (or complex) may give us an idea of the practical «utility». There are also elements which are useless, but are not rejected, because their rejection is difficult and moreover they must be cognized. Such is the case of a great number of spirits borrowed by the Tungus from their neighbours. They are not always rejected because of the fear of coming into conflict with these spirits. However, we have also seen the mechanism of their rejection, i.e. the forgetting of the function of the spirits, the loss of the ritual connected with the management of the spirits and lastly, the throwing of their names to complete oblivion. We have also seen what a burden such a complex may become, when it is fixed in a written form, as it is among the Manchus. So that the overgrowth of such a knowledge may result in is disfunction and the disequilibrium of the psychomental complex as a whole [714] with all the consequences resulting from such a state.
The psychomental complex itself may present obstacles to the including of new elements. Here I have in view some fundamental conceptions, the lack of which may cause the rejection of a new element. Let us suppose for a moment that the idea of mastering spirits is not accepted, then the whole system of shamanism and its elements would be rejected. However, when some of these elements included in shamanism are not in conflict with the existing complex, they may be adopted; but at the same time they will be adapted in a new function [715]. I shall revert to the problem of readaptation, but I shall now dwell upon some concrete cases observed among the Tungus. For instance, among the Tungus the idea of «master-spirits» in which means «master» of a region, mountain, animals etc., is not very common and it is not very important, as compared with what we know of other ethnical groups. Indeed, there are some spirits of this type, but most of them are of alien origin, as we have seen from the analysis. It is not easy to introduce among the Northern Tungus a new master-spirit, for the realm of natural phenomena among the Tungus is not so «misty» as it is among the groups which are not living in the forests and mountains; moreover, as shown there is a mechanism which checks the spreading of these ideas, viz. the fear of these spirits which would make life impossible. For this reason the Tungus unconsciously reject the ideas disturbing their economic activity. Should such a spirit be adopted, it would lose its «power» on the Tungus soil. Should too many spirits be introduced, the Tungus would be obliged to change their mode of life, or they would not be able to maintain their existence and in the psycho-mental complex it would be reasonable to expect a condition of disequilibrium with mass psychosis.
On the other hand, the Tungus will not accept the idea of the soul as a function, for their complex is lacking in theoretical premises — the physico-chemical principles of physiology — while a great number of facts points to the existence of an «immaterial» substance and a «soul» as independent phenomena, which can be separated from the body. Indeed, the idea of an ideal world, as it is pictured by the philosophers of the idealistic complex, might be easily accepted by the Tungus, but it will receive a more «material» interpretation — it will thus be adapted and remodelled.
We have seen that the Northern Tungus here treated have the idea of a supreme power lacking anthropomorphic features, which, however, is a «being». This idea seems to be very old and, owing to its existence, the Tungus very easily accept the idea of God, as professed by Christians. However, the real difficulty is met with when the Tungus must accept the idea of the Trinity and the human form of Jesus Christ, as well as his being born from a human being, Saint Mary. Those of them who are familiar with the complex of spirits, with its numerous manifestations, very easily accept the idea of the Trinity as independent of God, but a human being, Jesus Christ, turns into a «shaman» whose soul has become a spirit. This difficulty is due to the lack of important elements in the Tungus complex, namely, the intense interest of buga in human affairs, the idea of the saving of souls of sinners, and the possibility of buga descending to Earth in the form of a human being born of a human being because of a miraculous conception.» Some of these elements, in their remodelled form, may be accepted and adapted by the Tungus, but on the whole, the adoption of Christianity would mean the loss of the mechanism that regulates the Tungus psychomental life and the inevitable loss of their vital equilibrium, for the Tungus complex lacks specialists in psychiatry and special regulations of psychic phenomena by an intelligent government. The final effect would naturally be the absorption of the Tungus by other ethnical groups.
Thus, the assimilation of new elements is greatly limited. It depends on the primary milieu, the existing cultural adaptation, the density of population and especially on the existing psycho-mental complex. All these conditions of the Tungus ethnical units are the more resistant to the introduction of new elements, when they are well adjusted and the ethnical unit is stable in its equilibrium.
It may thus be formulated as follows: every cultural element (and complex) has its potential power of diffusion varying according to the milieu (primary and ethnical) in which it is spreading. Thus, potential power of diffusion varies from zero to an absolute and immediate acceptation of the element (and complex). In some of the above given instances we have seen that the elements of the psychomental complex are not always accepted in the form in which they are received, but are modified and adapted to the Tungus complex. The forms of adaptation are different, namely, there may be a formal change of the element (or complex), and there may be no formal change, but only a change of function in a different (Tungus) complex. Naturally both changes may also be combined. Here I give for illustration some examples. The modern army rifle is a weapon used for war, but when it is adopted by the Tungus it is used for hunting — which is a change of function. The same rifle may be made lighter by a reduction of its wooden parts and by removing some metallic parts — which is a formal change. In the adaptation of the elements of psychomental complex we may observe all degrees of changes. In fact, when for instance, the Tungus adopt Russian standards of measurement, they do not change them either in form or in function; the same is true in the extension of biological knowledge of animals, and practical methods of fighting diseases, for instance, by vaccination. The Chinese complex n'angn'ang preserves its function in the Tungus complex, but the list of manifestations is shortened. The Chinese prestidigitators tricks are used in theatrical performances for amusement; the Manchus borrow them as a component of shamanistic performance in which they assume a new function, especially in the trial of a new shaman, the same complex is shortened among the Tungus, but it preserves almost an identical function in their shamanism. The Mongol complex of onggun, which is a shamanistic spirit, equivalent to the Manchu vochko and the Northern Tungus seveng, is reduced in the Northern Tungus complexes to the term designating domesticated animals used as carriers of placings for spirit, seldom as riding animals for the clan spirits which are not mastered and are not connected with shamanism. Thus there are changes in form and function — so that only a term and a very vague connection with spirits in general may actually remain, We may observe variations of formal and functional changes of elements even when they are borrowed by the Tungus groups from other Tungus groups. When there is no formal change, but merely a functional change, the latter may be discovered only when the whole complex is very carefully investigated from the point of view of the respective groups, for as soon as a complex is transferred into a new ethnical milieu, it may lose altogether its former function. Indeed, every one of the indicated conditions of the existence of elements, after their being borrowed, may be illustrated with a great number of facts found in the present work, but a really source are the phonetic and semantic changes of sounding starters («words») which are well known to the linguists actually dealing with the ethnographical material which is the language as a functional phenomenon.
From the great number of facts discussed and expounded above it is evident that elements may be borrowed singly, or in groups and only very rarely as a large complex. The reason why the elements are not borrowed in large complexes is that the incorporation of a new complex is seldom possible; for such an incorporation of complex with a complete reconstruction of the whole cultural complex, save in exceptional cases, results in the loss of ethnical equilibrium, the further loss of ethnical independence and assimilation by other ethnical groups. Practically, elements of an alien complex are borrowed one by one, sometimes being accepted only by a small group of individuals of the ethnical unit and being at least slightly modified, and sometimes entirely changed in the process of adaptation. The process of fusion of groups of elements into a finished complex may last a very long time, and it may very often be left incomplete. Instances of this kind may be found among Tungus groups. The extensive complex of Buddhism began its penetration among the ancestors of the Manchus (the Manchus began to incorporate it into their complex) nearly ten centuries ago and it did not succeed in winning all Manchus. Another extensive complex, Christianity, began its spreading among the Tungus nearly three centuries ago and there is now not a single Tungus group which can be considered as having perfectly assimilated Christianity. However, as shown, a great number of Buddhistic and perhaps even Christian elements have been included in various Tungus complexes, sometimes in an unrecognizable form. Moreover, it has been shown that it was probably Buddhism which was directly responsible for the psychological stimulation of a new complex of shamanism, which was partly supplied with Buddhistic elements. In the complex of social organization the Northern Tungus clan, as it can be observed in Manchuria, was built up with the elements of the Manchu complex, but only a part of them, e.g. some terms, clan chief, etc. were incorporated. It may be noted that in this respect the Birarchen clan had more Manchu elements than the Kumarchen clan and the latter more than the Khingan Tungus clan. Some elements were doubled: the earlier Tungus elements were used beside the Manchu-Chinese elements, which is indicative of a process of further incorporation of new alien elements one by one. Still, there were very essential differences between the Birarchen clan and the Manchu clan.
I must dwell upon the problem of invention as a source of new elements in the Tungus complexes. Indeed, in the course of the present exposition of facts we have always been meeting with elements invented by the Tungus. In fact, every generalization further applied as an analytical instrument is an invention; any newly formed starter is an invention. These inventions are so common, and they are sometimes made simultaneously by so different persons, that their origin is even not noticed. It is especially true of those inventions which do not greatly affect the existing complexes. We have seen that every Tungus group has its own spirits («inventions» «hypotheses») which have no parallels in other groups, and we have met with hypotheses individually proposed and sometimes accepted by more or less larger groups in the process of formation of a new complex dealing, for instance with the explanation of psychic phenomena, a great number of elements may be borrowed from the neighbours inter-ethnical milieu — while the lacking elements may be invented. Such are e.g. the shaman's own spirits that are supposed to influence the other spirits which affect a person. As in the case of formation of new «words» from the known components, practiced by every child, and as in the case of formation of new «words» for new phenomena (vide supra e.g. ichenki, — «binocular») in similar psychological conditions of individuals treated by the shamans, the latter naturally come to similar new methods, whence absolutely similar situations and attitudes of the patient and the shaman will appear, about which it would be impossible to say, whether they are invented or borrowed, if we have no definite historical record [717], or evidences of the geographical distribution. The importance of the diffusion of cultural elements and complexes, and that of the parallelism of invention were overestimated to make of them the great ethnological problems, only because facts were selected to prove one or another aspect in the formation of complexes and because the attention of theoreticians was chiefly attracted by striking (for them) elements and complexes, while the greater mass of facts was omitted altogether [718]. Both, diffusion and parallelism of invention are the most common phenomena of similarity of elements in different Tungus groups.
However, among the Tungus the part of invention requires some additional remarks. I have now not picked out cases of Tungus invention that would be striking in the eyes of Europeans, for such are not needed to demonstrate the mechanism of variations and formation of the Tungus complexes. Besides, the selection of such cases would by no means be easy, because the European eye can be struck only by inventions which could be used in the European complex, and the number of such inventions is certainly restricted, because of the difference between the complexes. One condition more is to be taken into account, namely, the potential power of invention among the Tungus cannot be very high because the Tungus are not numerous. In fact, inventions reproduced when needed or when incidentally made by individuals, so that the greater the number of people, the greater the potential power of invention. On the other hand, inventions of a disturbing type («striking» in the observer's eye) are made when the ethnical unit is found under conditions of a rapid tempo of variation stimulated by positive impulses and, as shown, greatly conditioned by the interethnical milieu. This is not the case with most of the Tungus groups. One realizes the importance of invention, when one considers the limited number of the Tungus, their cultural complex (well balanced and perfectly adapted to the size of the population and the conditions of primary milieu) and even the minutely worked out system of regulation of psychic life which is greatly disturbed by a comparatively powerful interethnical pressure.
If now we remember what has been said above in reference to the limitations of adoption and to the adaptation of cultural elements, it will be evident that the Tungus, who derive their cultural elements from the same source, e.g. Chinese or Mongol, may sieve and modify them to the point of complete impossibility to recognize these elements. It is especially so when the borrowed elements are added to the previously existing complex and then, or even later, a new complex is supplied with the elements created on the spot in fact, a series of complexes within different units may be formed which may have the appearance of «common origin», or at least of being copied from a pre-existing model, while actually they may be merely the product of individual adaptation to the complexity of conditions of milieus -the primary milieu, which fixes its limitations and imposes definite forms, the secondary of the cultural milieu, created by the unit, which is always changing, the tertiary milieu, from which new elements are borrowed, and the inherited morphological and physiological complexes, first of all formed in individuals and cognized by the reaction of individuals. Hazardous and responsible is a further step in the classification of the observed phenomena, namely, the association of formed complexes with groups of individuals - firstly, among the individuals of the grouping in the natural unit of the family; secondly, among the individuals grouped into clans; thirdly, in still larger ethnical units and other units, when they are markedly differentiated. Some of the cultural elements are not correlated at all with these units, as such, while other elements are not only correlated, but may be a form of adaptation of these units. For instance, within certain limits the knowledge of the primary milieu may be confined to the family in which it is found and transmitted [719], shamanism is essentially a clan or a territorial function, and all of its theoretical background is transmitted to and found in these larger units [720]; the complex of reactions and positive knowledge, with the theoretical background, as to other ethnical units is essentially a function of ethnical units. However, as I have shown, the ethnical units themselves are only the visible manifestations of a process which I have called ethnos. Therefore, when the complexes are separated from the concrete units, with which they are functionally «correlated» — it must be emphasized that the existence of units may be recognized from the fact of these functions only — these become meaningless abstractions with which one cannot operate. However, such abstractions may serve as a method of rough classification, chiefly for the memorizing of observed facts.
Thus the complexes, as they are treated here, ought to be also distinguished from the point of view of their connection with the concrete units within which they are created and for which they are needed. Indeed, such a larger complex as shamanism includes elements functionally connected with individuals, families and clans (or territorial spirits), and the same elements may enter into different complexes. For instance, the knife carried by every Tungus may be used: (1) for cutting food (food-utensil complex) (2) for hunting when there is no other weapon (hunting complex), and (3) for self-defense and attack from and on human beings («war» complex). The same is true of some elements of the psychomental complex which may have different functions in different complexes within the same ethnical unit. However, there are some elements which have only one connection, i.e. with one of the complexes.
Thus from the point o view of the history of formation
of complexes and from the point of view of their function in ethnical units the
complexes cannot generally be regarded as entities which exist by themselves.
They are chiefly a scientific method of classification of facts for the
convenience of exposition and memorizing. One cannot arrive at a clear
understanding of the existence of the Tungus ethnical units by an abstraction
of such complexes [721].
713. When a group is affected, then a strong centripetal movement is naturally formed within it, which has its effect of increase of the centrifugal movement in the greater unit as a whole. Such a differentiated unit may also easily become a foreign body within the greater unit. Such seems to be the case, when interethnical pressure in the form of «cultural influence» affects only a part of the population.
714. The same may happen with the knowledge of the European groups and it seems to have happened in formerly prosperous ethnical groups of Western Asia, and perhaps in Egypt.
715. For this reason shamanism cannot be assimilated, e.g. by the Russians, who oppose the idea of mastering spirits. In exceptional cases, when this idea is accepted by Russians, the latter present a typical picture of psychopathologically affected individuals (I shall revert to this question). The same relates to the Chinese, in whose complex this idea leads to professional magic.
716. The last idea has no success among naturalistically minded Tungus, but it may be easily adopted by the Manchus who, at least theoretically, accept the idea of conception from the class of enduri.
717. Even a term by which the new invention is designated may be misleading, for the term, even an alien one, may come later, i.e. after the cognition of the new phenomenon, and it may create an impression of borrowing of the element.
718. There are special psychological conditions which perfectly explain why this question attracted so much attention and sometimes produced animated discussions. If we observe these phenomena in a great number of units, we may notice that the great inventions are usually connected with the ethnical units which in the interethnical milieu play a very important part at certain historic moments. They are usually connected with the leading ethnical units and with those which are so potentially, or which recently were so. We have seen that an ethnical unit which shows comparatively a great increase of population and a great change of the cultural adaptation has a greater chance of becoming a leading ethnos. For such a unit the change of cultural adaptation and consequently continuous invention is the primary condition of success, for of all units it must be the best adapted. Therefore the psychomental energy is naturally directed towards invention as a matter of fact, without invention there is no possibility of adaptation to the new condition of an increased population. Among thousands of ethnical units a few of them usually spend their efforts on inventions, while the other units imitate them, when the inventions are of adaptive interest or when they are attractive for various reasons. Since the stimulus of becoming «leading» is great and since the benefits of invention are quite clear, more attention of the investigators was attracted to the phenomenon and the function of striking inventions than was actually deserved in the life-history of ethnical units and particularly in the formation of new complexes. It may also be pointed out that for some time «invention» was especially attractive to those theoreticians who were puzzled by their own idea of «progress» and all practical consequences resulting from it as to the policy and behaviour to be adopted for better achievement of «progress». Naturally the investigators who were dealing with leading ethnoses (this is the common case with historians particularly attracted by leading ethnos) were inclined to over-estimate the invention-factor; those who were dealing with the «backward», «primitive» ethnical units or merely non-leading units were more inclined to see elements of diffusion, borrowing etc. The phase of the process ethnos manifested in «leading ethnos» was taken for inherited genius, so that this idea greatly handicapped further penetration into the ethnological process in mankind. Indeed, such a belief becomes especially natural among the leading and potential leading ethnical units, for it justifies their attitude of aggression towards other «inferior» units and it further spreads among the non-leading ethnical units which accept their position of being led and influenced by the leading ones. This, in its turn, facilitates consolidation of leading ethnical units and thus such an attitude belongs to the mechanism of interethnical equilibria.
719. A similarity of these complexes observed in different units within a clan or territorial or ethnical unit is not a character pointing to their functional connection with these larger units.
720. A similarity of shamanism in different clans and even in different ethnical units is not indicative of its functional connection with the larger units.
721. Indeed, the operation of investigators with the complexes greatly facilitates the recording of facts and their exposition. The idea of regarding complexes in their abstractions has been common in other sciences as well. For instance, formally different physiological functions, such as reproduction, blood circulation, metabolism, high nervous activity etc. were regarded as complexes, but at present one is more and more inclined to regard these «complexes» as functions which depend on the whole of the animal organism. For instance, a definite correlation between the constitutions, which themselves are expressions of «several complexes», and the character as an average common behaviour of the individual, seems to be a fact; so that since character is the most complex manifestation of adaptation, one turns one's eyes to the constitution, as to the primary condition of the character, and to the ethnical milieu in which it is manifested. A «psychological» approach to the problem of character is impossible, unless one gives a new meaning to «psychological». The «complex» of reproduction, intimately connected with a series of organs, like glands of internal secretion, nervous (central and peripheral) systems, and even ethnical milieu, can be no more regarded as a complex by itself. The same is true of the thinking process which is done by the whole organism and cannot be confined to the brain alone. Limitations as to the use of complexes put new requirements for the investigator, much greater than before, but it does not mean that these limitations must be rejected on the ground of the difficulties involved by the limitations.