Lev Vygotsky 1934

The Problem of Age


A chapter in the book on developmental child psychology that Vygotsky was preparing during the last years of his life, first published in The Collected Works of L. S. Vygotsky, Volume 5, 1998, pp. 187-205. Transcribed by Andy Blunden, 2008.


1. The Problem of Dividing the Child’s Development Into Periods

According to theoretical bases, the schemes for dividing the child’s development into periods proposed in science can be placed into three groups.

The first group includes attempts to divide childhood into periods not by separating the course itself of the child’s development, but on the basis of a stepwise construction of other processes that are connected in some way with the child’s development. As an example, we might cite the division of child development into periods that is based on the biogenetic principle. The biogenetic theory assumes that there is a strict parallelism between the development of humanity and the development of the child, that ontogenesis repeats phylogenesis in a brief and compressed form. From the point of view of this theory, it is most natural to divide childhood into separate periods conforming basically to the periods of the history of mankind. Thus, dividing childhood into periods is based on the division into periods of phylogenetic development. This group includes the proposals of Hutchinson and other authors on dividing childhood into periods.

Not all the attempts of this group are equally unfounded. For example, this group includes the attempt to divide childhood into periods corresponding to levels of training and education of the child, breaking up the system of national education accepted in a given country (preschool age, primary school age, etc.). In this case, breaking childhood up into periods is done not on the basis of internal breaking up of development itself, but, as we see, on the basis of training and education. This is where the error of this scheme lies. But since the processes of child development are closely connected with the teaching of the child, and the separation of teaching into levels depends on enormous practical experience, then naturally breaking childhood up according to a pedagogical principle brings us extremely close to a real division of childhood into separate periods.

Most of the attempts must be placed into a second group; these are directed toward isolating some single trait of child development as an arbitrary criterion for dividing it into periods. A typical example is the attempt of P P Blonsky (1930, pp. 110-111) to divide childhood into periods on the basis of dentition, that is, the appearance of teeth and their replacement. The trait serving as a basis for separating one period of childhood from another must be (1) an indicator for judgment on the general development of the child, (2) easily accessible visually, and (3) objective. Dentition meets precisely these requirements.

Dentition processes are closely connected with essential features of the constitution of the growing organism, specifically with its calcification and the activity of the glands of internal secretions. At the same time, these processes are easily accessible for observation and indisputably established. Dentition is a clear age trait. On the basis of dentition, postnatal childhood is divided into three periods: toothless childhood, the childhood of milk teeth, and the childhood of permanent teeth. Toothless childhood lasts until all of the milk teeth come through (from eight months to two or two and a half years). The childhood of milk teeth lasts to the beginning of tooth replacement (approximately age six and a half years). Finally, the childhood of permanent teeth concludes with the appearance of the third set of back molars (wisdom teeth). The period of breaking through of the milk teeth can in turn be divided into three stages: absolutely toothless childhood (the first half year), the stage of breaking through of the teeth (second half year) and the stage of breaking through of the canines and molars (the third year of postnatal life).

A similar attempt to divide childhood into periods on the basis of some single aspect of development is the scheme of C. H. Stratz, who proposed sexual development as the main criterion. Psychological criteria have been suggested in other schemes constructed along the same principle. This is the kind of division into periods proposed by W Stern, who differentiates early childhood as the time during which the child displays only play activity (up to six years of age) followed by a period of conscious learning in which play and work are separated and a period of youthful maturation (age fourteen to eighteen) with the development of independence of personality and plans for subsequent life.

The schemes of this group are, first of all, subjective. Although as a criterion for dividing age levels, they do isolate an objective trait, the trait itself is taken according to subjective bases depending on which processes get the most attention. Age is an objective category and not an arbitrary, freely chosen, fictive value. For this reason, guideposts that mark age may be placed not at any points of the life of the child, but exclusively and only at those points at which objectively one age level ends and another begins.

Another inadequacy of schemes in this group is that they use a single criterion, some single trait, for separating all the age levels. What is forgotten here is that in the course of development the value, the significance, the indicative and symptomatic quality and importance of the selected trait changes. The trait that is indicative and substantive for making a judgment on the development of the child at one period loses its meaning in the following period since in the course of development, aspects that were primary earlier become secondary. Thus, the criterion of sexual maturation is significant and indicative for the age of puberty, but has no such meaning for the preceding age levels. The breaking through of teeth at the boundary between infancy and early childhood can be used as an indicative trait for the general development of the child, but the replacement of teeth at approximately seven years of age and the appearance of wisdom teeth cannot be compared in its significance for general development to the first appearance of teeth. These schemes do not take into account the reorganization of the process itself of development. Because of this reorganization, the importance and significance of any trait change continuously with the transition from age level to age level. This excludes the possibility of dividing childhood into separate periods according to a single criterion for all age levels. Child development is such a complex process that it cannot be determined at all completely according to one trait alone at any stage.

The third inadequacy of the schemes is their principal tendency to study external traits of child development and not the internal essence of the process. In theory, the internal essence of things and the external form of their manifestation do not coincide. “... If the form of manifestation and the essence of things coincided directly, then all science would be superfluous ...” (K. Marx and E Engels, Works, Vol. 25, Part II, p. 384). For this reason, scientific research is an indispensable means for recognizing the reality that the form of manifestation and the essence of things do not coincide directly. At present, psychology is moving from a purely descriptive, empirical, and phenomenological study of phenomena to disclosing their internal essence. Until recently, the main problem was the study of symptom complexes, that is, the aggregate of external traits that differentiate the various periods, stages, and phases of child development. Symptom denotes trait. To say that psychology studies symptom complexes of different periods, phases, and stages of child development is to say that it studies its external traits. But the real problem consists of studying what lies behind these traits and determines them, that is, studying the process itself of child development in its internal patterns. With respect to the problem of dividing childhood into periods, this means that we must reject attempts of symptomatic classification of age levels and move on, as other sciences have done in their time, to classification based on the internal essence of the process being studied.

A third group of attempts to divide child development into periods is connected with the attempt to move from a purely symptomatic and descriptive principle to isolating substantial features of child development itself However, in these attempts, the problem is formulated correctly but not solved. Attempts to solve problems always seem to be half-hearted, never proceed to the end, and are unsustainable with respect to the problem of periodicity. Methodological difficulties that result from an antidialectical and dualistic concept of child development are a fateful obstacle that prevents it from being considered as a single process of self-development.

Such, for example, is the attempt of A. Gesell to construct periodicity of child development on the basis of the change in the child’s internal rhythm and tempo, on the basis of determining “the flowing stream of development.” Based on essentially correct observations of the change in the rhythm of development related to age, Gesell arrives at separating all of childhood into separate rhythmic periods or waves of development united within themselves by a constancy of tempo over the whole duration of a given period and separated from other periods by a clear change in this tempo. Gesell presents the dynamics of child development as a process of gradual slowing of growth. Gesell’s theory borders on the group of contemporary theories that, in his own expression, make early childhood the high point for the interpretation of the personality and its history. What is main and most important in child development, according to Gesell, is accomplished in the first years or even in the first months of life. Subsequent development taken as a whole does not equal one act of this drama that is maximally saturated with content.

What is the source of such delusion? It flows inevitably from the evolutionistic conception of development on which Gesell bases his theory and according to which nothing new arises in development, no qualitative changes occur, and only what is given from the very beginning grows and develops. Actually, development is not confined to the scheme, “more – less,” but is characterized primarily and specifically by the presence of qualitative neoformations that are subject to their own rhythm and require a special measure each time. It is true that at early age levels, we observe maximum rates of development of those prerequisites on which subsequent development of the child depends. The basic, elementary organs and functions mature sooner than the higher. But it is not correct to assume that all development is exhausted by the growth of these basic, elementary functions which are the prerequisites for higher aspects of the personality. If we consider higher aspects, then the result will be the reverse; the tempo and rhythm of their establishment will be minimal during the first acts of the whole drama of development and will reach a maximum in its finale.

We cited Gesell’s theory as an example of half-hearted attempts at periodicity which stop halfway in the transition from symptomatic to essential division of age levels.

What must the principles be for constructing a genuine periodicity? We already know where to look for its real basis: only internal changes of development itself, only breaks and turning points in its flow can provide a reliable basis for determining the main periods of formation of the personality of the child which we call age levels. All theories of child development can be reduced to two basic conceptions. According to one, development is nothing other than realization, modification, and combination of deposits. Nothing new develops here – only a growth, branching, and regrouping of those factors that were already present at the very beginning. According to the second conception, development is a continuous process of self-propulsion characterized primarily by a continuous appearance and formation of the new which did not exist at previous stages. This point of view captures in development something essential to a dialectical understanding of the process.

In its turn, it allows both idealistic and materialistic theories of personality construction. In the first case, it finds its embodiment in theories of creative evolution directed by an autonomous, internal vital surge of the purposefully self-developing personality, by the will toward self-affirmation and self-perfection. In the second case, it leads to an understanding of development as a process that is characterized by a unity of material and mental aspects, a unity of the social and the personal during the child’s ascent up the stages of development.

From the latter point of view, no other criterion exists or can exist for determining the concrete periods of child development or age levels except for those neoformations that characterize the essence of each age level. We must understand that new type of structure of the personality and its activity, those mental and social changes which first appear at a given age level and which mainly and basically determine the consciousness of the child, his relation to the environment, his internal and external life, the whole course of his development during the given period as age-related neoformations.

But this alone is not enough for dividing child development into periods scientifically. We must also consider its dynamics and the dynamics of transitions from one age level to another. By purely empirical studies, psychology established that age-level changes may, in the words of Blonsky (1930, p. 7), occur abruptly and critically, or may occur gradually and lytically. [i.e., fading from one to the next] Blonsky terms as periods and stages the times of the child’s life that are separated from one another by more (periods) or less (stages) abrupt crises; phases are times of the child’s life separated from each other lytically.

Actually, at certain age levels, development is marked by slow, evolutionary, or lytic flow. These are age levels of predominantly smooth and frequently unremarkable internal change in the child’s personality, change that is accomplished by insignificant “molecular” attainments. Here, over a more or less long time that usually takes several years, no fundamental, abrupt shifts and alterations occur that reconstruct the child’s whole personality. More or less remarkable changes in the child’s personality occur here only as a result of a long-term cryptic “molecular” process. They appear outside and are accessible to direct observation only as a conclusion of long-term processes of latent development.

During relatively firm or stable ages, development occurs mainly through microscopic changes in the child’s personality that accumulate to a certain limit and then appear spasmodically in the form of some kind of neoformation of the age level.

Such stable periods make up the greater part of childhood, if judged purely chronologically. Since within them, development proceeds as if underground, great alterations in his personality are evident if a child is compared at the beginning and at the end of a stable period.

Stable age periods have been studied significantly more fully than those that are characterized by another type of development – crises. The latter are disclosed purely empirically and thus far have not been brought into the system, have not been included in the general division of child development into periods. Many authors even doubt that there is any internal need for their existence. They are more inclined to take them as “diseases” of development because of its deviation from the normal path. Almost none of the bourgeois investigators could theoretically realize their actual. significance. For this reason, our attempt to systematize them and interpret them theoretically and include them in the general pattern of child development must be considered as almost the first such attempt.

None of the investigators can deny the fact itself of the existence of these unique periods in child development, and even authors with the most nondialectical frame of mind admit the need to allow, if only as a hypothesis, the presence of crises in the child’s development even in earliest childhood.

From a purely external aspect. these periods are characterized by traits which are the opposite of the firm or stable age levels. During these periods, abrupt and major shifts and displacements, changes, and discontinuities in the child’s personality are concentrated in a relatively short time (several months, a year or at most, two). In a very short time, the child changes completely in the basic traits of his personality. Development takes on a stormy, impetuous, and sometimes catastrophic character that resembles a revolutionary course of events in both rate of the changes that are occurring and in the sense of the alterations that are made. These are turning points in the child’s development that sometimes take the form of a severe crisis.

The first feature of such periods consists, on the one hand, in the fact that the boundaries that separate the beginning and end of the crisis from adjacent age levels are not at all definite. The crisis arises imperceptibly – it is difficult to determine its onset and termination. On the other hand, an abrupt aggravation of the crisis, which usually occurs in the middle of this age period, is characteristic. The presence of a culmination point in which the crisis reaches apogee characterizes all critical ages and differentiates them clearly from the stable periods of child development.

The second feature of critical age levels served as a departure point for empirical study. The fact is that a significant proportion of children who experience critical periods of development are difficult children. These children seem to drop out of the system of pedagogical influence that until very recently provided a normal course for their training. and education. In children of school age during critical periods, there is a drop in rate of success, a slacking of interest in school work, and a general decline in capacity for work. At critical age levels, the child’s development frequently is accompanied by more or less sharp conflicts with those around him. The child’s internal life is sometimes connected with painful and excruciating experiences and with internal conflicts.

True, it is far from always that all of this occurs. In different children, critical periods occur differently. During the passage of a crisis even in children most alike in type of development and in social situation, there is much greater variation than during the stable periods. Many children do not exhibit at all clearly any of the traits of difficult children or any decline in school success. The range of variation in the passage of these age levels in different children and in the influence of external and internal conditions on the course of the crisis itself is so great and significant that this caused many authors to question whether crises of child development in general are not a product of exclusively external unfavorable conditions and whether they should therefore be considered the exception rather than the rule in the history of child development (A. Busemann et al.).

It is understood that external conditions determine the concrete character of manifestation and passage of critical periods. Dissimilar in different children, they bring about a very mixed and diverse picture of variants of the critical age. But neither the presence nor the absence of some specific external conditions, but internal logic of the process of development itself is responsible for the critical, disruptive periods in the life of the child. A study of comparative factors convinces us of this.

Thus, if we move from an absolute evaluation of the difficult aspects of difficult children to a relative evaluation based on a comparison of degrees of case or difficulty of teaching the child during the stable period that either preceded or followed the crisis, we cannot help but see that every child at this stage becomes relatively difficult in comparison with himself at a proximate age. In precisely the same way, if we move from absolute evaluation of school success to a relative evaluation based on a comparison of the rate of movement of the child in the course of teaching at different age periods, we will see that every child slows this rate during the crisis period in comparison with the rate characteristic of the stable periods.

The third feature, perhaps most important but least clear from the theoretical aspect and for this reason, one that impedes a correct understanding of the nature of child development during these periods, is the negative character of development. Everyone who wrote about these unique periods noted in the first place that development here is different from that in the stable ages and does destructive rather than constructive work. Progressive development of the child’s personality, the continuous construction of the new, which had been so prominent in all stable ages, is seemingly attenuated or temporarily suspended. Processes of dying off and closure, the disintegration and breakdown of what had been formed at preceding stages and distinguished the child of a given age move to the forefront. During the critical periods, the child does not so much acquire as he loses some of what he had acquired earlier. The onset of these age levels is not marked by the appearance of new interests of the child, of new aspirations, new types of activity, new forms of internal life. The child entering a period of crisis is more apt to be characterized by the opposite traits: he loses interests that only yesterday guided all his activity and took the greater part of his time and attention but now seemingly die off, forms of external relations and internal life developed earlier are neglected. L. N. Tolstoy graphically and precisely called one such critical period of child development the desert of adolescence.

This is what people have in mind primarily when they speak of the negative character of the critical age levels. By this, they mean to express the idea that development seems to change its positive, creative significance, causing the observer to characterize such periods predominantly from unfavorable, negative aspects. Many authors are even convinced that the negative content exhausts the whole idea of development during the critical periods. This conviction is fixed in the names for the critical years (some call this age the negative phase, some, the phase of obstinacy, etc.).

The concepts of separate critical ages were introduced into science by the empirical path and in a random order. The crisis of age seven was discovered and described before the others (the seventh year in the life of the child is transitional between the preschool and the adolescent periods). The seven- to eight-year-old child is no longer a preschooler, but, not an adolescent. The seven-year-old differs from both the preschool child and from the school child and for this reason presents difficulties with respect to his teaching. The negative content of this age is apparent primarily in the disruption of mental equilibrium and in the instability of the will, mood, etc.

The crisis of the three-year-old, discovered and described later, was called by many authors the phase of obstinacy or stubbornness. During this period, limited to a short interval of time, the personality of the child undergoes abrupt and unexpected changes. The child becomes a difficult child. He exhibits obstinacy, stubbornness, negativism, capriciousness, and self-will. Internal and external conflicts frequently accompany the whole period.

The thirteen-year crisis was studied even later and described as the negative phase of the age of sexual maturation. As the very name indicates, the negative content of the period is most prominent and with superficial observation seems to be the whole idea of development in this period. The decrease in success, decline in capacity for work, lack of harmony in the internal structure of the personality, contraction and dying off of systems of previously established interests, and the negative, protesting character of behavior led Kroh to describe this period as the stage of such disorientation in internal and external relations in which the human “I” and the world are more divided than at any other periods.

Comparatively recently the idea has been recognized theoretically that the transition from infancy to early childhood, occurring at approximately age one, also presents an essentially critical period with its own differentiating traits known to us from the general description of this unique form of development; this transition has been thoroughly studied from the factual aspect.

To obtain a definitive chain of critical ages, we proposed including in it as an initial link, perhaps the most unique of all periods of child development, the new-born stage. This well-studied period stands alone in the system of other ages and is, by its nature, perhaps the clearest and least questionable crisis in the development of the child. The spasmodic change in conditions of development in the act of birth, when the newborn rapidly falls into a completely new environment, changes the whole tenor of his life and characterizes the initial period of extra-uterine development.

The crisis of the newborn separates the embryonal period of development from infancy. The one-year crisis separates infancy from early childhood. The crisis at age three is a transition from early childhood to preschool age. The crisis at age seven is a link that joins preschool and school ages. Finally, the crisis at age thirteen coincides with the turning point in development at the transition from school age to puberty. Thus, an ordered picture opens before us. Critical periods alternate with stable periods and are turning points in development, once again confirming that the development of the child is a dialectical process in which a transition from one stage to another is accomplished not along an evolutionary, but along a revolutionary path.

If the critical ages had not been discovered through purely empirical means, the conception of them would have to be introduced into the pattern of development on the basis of theoretical analysis. Now it remains for theory only to become cognizant of and comprehend what has already been established by empirical studies.

At turning points of development, the child becomes relatively difficult due to the fact that the change in the pedagogical system applied to the child does not keep up with the rapid changes in his personality. Pedagogy during the critical ages is least developed in practical and theoretical respects.

As all life is at the same time also a dying (E Engels), so also child development – one of the complex forms of life – of necessity includes in itself processes of closure and dying off. The appearance of the new in development necessarily signifies the dying off of the old. The transition to a new age is always marked by the demise of the previous age. The processes of reverse development, the dying off of the old, are concentrated mainly during the critical ages. But it would be a great mistake to assume that this is the whole significance of the critical ages. Development never ends its creative work, and during critical periods too, we observe constructive processes of development. Moreover, processes of involution [regression] so clearly expressed during these periods, themselves are subordinate to Processes of positive structuring of the personality, depend on them directly, and with them make up an indivisible whole. The disruptive work is done in these periods to the extent that is required by the need to develop properties and traits of the personality. Practical study shows that the negative content of development at turning points is only the reverse or shadow side of positive changes of the personality that make up the principal and basic sense of any critical age.

The positive significance of crisis at age three is evident in that here new character traits of the child’s personality appear. It has been established that if the crisis for some reason passes sluggishly and is not clearly expressed, this leads to a serious delay in the development of affective and volitional aspects of the child’s personality at a later age.

With respect to the crisis at age seven, all investigators noted that together with negative symptoms, during this period, there are a number of major achievements: the child becomes more independent and his relation to other children changes.

In the crisis at age thirteen, the decrease in productivity of mental work of the student is caused by a change from attention to what is obvious to understanding and deduction. The transition to a higher form of intellectual activity is accompanied by a temporary decrease in capacity for work. This is also confirmed for the rest of the negative symptoms of the crisis: behind every negative symptom is hidden a positive content consisting usually in the transition to a new and higher form.

Finally, there is no doubt that there is positive content in the crisis at age one. Here the negative symptoms are obviously and directly connected with positive acquisitions that the child makes by standing up and by learning to speak.

The same may pertain also to the crisis of the newborn. At this time, the child regresses at first even with respect to physical development: in the first days after birth, the newborn loses weight. Adaptation to the new form of life places such high demands on the vitality of the child that, in the words of Blonsky, man never stands as close to death as in the hours of his birth (1930, p. 85). Nevertheless, during this period more than at any of the subsequent crises, the fact is evident that development is a process of the formation and appearance of the new. Everything that we see in the child’s development during the first days and weeks is a continuous neoformation. Negative symptoms that characterize the negative content of this period arise from the difficulties due specifically to the novelty of the form of life that arises for the first time and is much more complicated.

The most essential content of development at the critical ages consists of the appearance of neoformations which, as concrete research shows, are unique and specific to a high degree. Their main difference from neoformations of stable ages is that they have a transitional character. This means that in the future, they will not be preserved in the form in which they appear at the critical period and will not enter as a requisite component into the integral structure of the future personality. They die off, seemingly being absorbed by the neoformations of the subsequent, stable age and being included in their composition as subordinate factors that do hot have an independent existence, being dissolved and transformed in them to such an extent that without special and penetrating analysis, it is frequently impossible to detect the presence of this transformed formation of the critical period in the acquisitions of the succeeding stable age. As such, the neoformations of the crises die off together with the onset of the following age, but they continue to exist in a latent form within it, not living an independent life, but only participating in the underground development which leads to the spasmodic appearance of neoformations during the stable ages, as we have seen.

The concrete content of general laws on neoformations of stable and critical ages will be disclosed in subsequent sections of this work devoted to considering each age.

Neoformations must serve as the basic criterion for dividing child development into separate ages in our scheme. In this scheme, the sequence of age periods must be determined by the alternation of stable and critical periods. The times of stable ages that have more or less distinct beginning and end boundaries can most correctly be determined specifically according to these boundaries. Because of the different character of their passage, critical ages can be determined most correctly by noting the culmination points or peaks of the crisis and using as its beginning the preceding half year closest to this time, and for its conclusion, the closest half year of the subsequent age.

As was established by empirical study, stable ages have a clearly expressed two-member structure and can be divided into two stages, the first and the second. Critical ages have a clearly expressed three-member structure and consist of three interconnected lytic transitions of phases: pre-critical, critical, and post-critical.

It must be noted that our scheme of child development differs substantially from other similar schemes in the determination of basic periods of child development. In addition to using the principle of age-related neoformations as criteria, the following points are new in this scheme: (1) introducing critical ages into the scheme of division into periods; (2) excluding the period of embryonal development of the child; (3) excluding the period of development that is usually called youth, which includes the years_ after age seventeen to eighteen right up to the onset of final maturity; (4) including the age of sexual maturation among the stable, firm ages and not among the critical ages.

We remove the embryonal development of the child from the scheme for the simple reason that it cannot be considered at the same level as extra-uterine development of the child as a social being. The embryonal development is a completely special type of development subject to patterns other than development of the personality that begins at the moment of birth. Embryonal development is studied by an independent science, embryology, which cannot be considered a chapter of psychology. Psychology must take into account the laws of embryonal development of the child since the features of this period affect the course of subsequent development, but psychology does not include embryology in any way because of this. In precisely the same way, it is necessary to consider the laws and data of genetics, that is, the science of heredity, without turning genetics into one of the chapters of psychology. Psychology does not study either heredity or uterine development as such, but only the influence of heredity and uterine development of the child on the process of his social development.

We do not include youth in the scheme of age periods of childhood for the reason that theoretical and empirical studies equally compel opposition to stretching child development excessively and including in it the first twenty-five years of human life. In the general sense and according to basic patterns, the age eighteen to twenty-five years more likely makes up the initial link in the chain of mature age than the concluding link in the chain of periods of child development. It is difficult to imagine that human development at the beginning of maturity (age eighteen to twenty-five) could be subject to patterns of child development.

Including the age of puberty among the stable ages is a necessary logical conclusion from what we know about this age and what characterizes it as a period of enormous development in the life of the adolescent, as a period of higher syntheses effected in the personality. This arises as. the necessary logical conclusion from the criticism that in Soviet science theories were imposed that reduced the period of sexual maturation to “normal pathology” and to a profound internal crisis.

Thus, we could present the division of age into periods in the following ways:

Crisis of the newborn.
Infancy (two months to one year).
Crisis at age one.
Early childhood (one to three years).
Crisis at age three.
Preschool age (three to seven years).
Crisis at age seven.
School age (eight to twelve years).
Crisis at age thirteen.
Age of puberty (fourteen to eighteen years).
Crisis at age seventeen.

2. Structure and Dynamics of Age

The task of this section is to establish the general states that characterize the internal structure of the process of development that we call the structure of age in each period of childhood.

The following is the most general state which we must indicate immediately: the process of development in each age period, regardless of all the complexity of its organization and composition, regardless of all the diversity of the partial processes that form it, that are disclosed by analysis, represents a single whole that has a certain structure; the structure and course of each partial process of development that is included in the constitution of the whole is determined by the laws of construction of this whole or by structural laws of the age level. An integral formation that is not made up entirely of separate parts, being a kind of aggregate, but itself determines the fate and significance of each of the parts that make it up is called a structure.

The age levels represent the integral, dynamic formation, the structure, which denies the role and relative significance of each partial line of development. At each given age period, development occurs in such a way that separate aspects of the child’s personality change and as a result of this, there is a reconstruction of the personality as a whole – in development there is just exactly a reverse dependence: the child’s personality changes as a whole in its internal structure and the movement of each of its parts is determined by the laws of change of this whole.

As a result of this, at each given age level, we always find a central neoformation seemingly leading the whole process of development and characterizing the reconstruction of the whole personality of the child on a new base. Around the basic or central neoformation of the given age are grouped all the other partial neoformations pertaining to separate aspects of the child’s personality and the processes of development connected with the neoformations of preceding age levels. The processes of development that are more or less directly connected with the basic neoformation we shall call central lines of development at the given age and all other partial processes and changes occurring at the given age, we shall call peripheral lines of development. It is understood that processes that are central lines of development at one age become peripheral lines of development at the following age and conversely, peripheral lines of development of one age are brought to the forefront and become central lines at another age since their meaning and relative significance in the total structure of development changes and their relation to the central neoformation changes. Thus, in the transition from one stage to another, the whole structure of the age is reconstructed. Each age has a unique and singular structure specific to it.

We shall elucidate this with examples. If we stop to consider the consciousness of the child, understood as his “relation to his environment” (K Marx), and if we take consciousness generated by physical and social changes of the individual as an integral expression of higher and most essential features in the structure of the personality, then we shall see that in the transition from one age level to another, it is not so much separate partial aspects of consciousness, its separate functions or methods of activity that develop, as it is that primarily the general structure of consciousness changes which at each given age is characterized mainly by a certain system of relations and dependencies between its separate aspects and separate forms of the individual’s activity.

It is completely understandable that with the transition from one age level to another, together with a general reconstruction of the system of consciousness, the central and peripheral lines of development change places. Thus, when the development of speech appears in early childhood, it is so closely and directly connected with the central neoformations of the age that as soon as the child’s social and objective consciousness appears in its most incipient configurations, speech development cannot but be attributed to the central lines of development of the period under consideration. But during school age, the continuing development of the child’s speech is in a completely different relation to the central neoformation of this age and, consequently, must be considered as one of the peripheral lines of development. During infancy, when preparation for speech development in the form of babbling occurs, these processes are connected with the central neoformation of the period in such a way that they must also be placed in the peripheral lines of development.

Thus we see that one and the same process of speech development may act as a peripheral line in infancy, become the central line of development in early childhood, and again be converted to a peripheral line in subsequent age periods. It is completely natural and understandable that in direct and immediate dependence on this, speech development, considered as such, will in itself occur completely differently in each of these three variants.

The alternation of central and peripheral fines of development with the transition from age level to age level leads us directly to the second problem of this section – to the question of the dynamics of the appearance of neoformations. Once again, as in the problem of the structure of age, we must limit ourselves to the most general explanation of the concept, leaving the concrete disclosure of the dynamics of age changes for later chapters dealing with a survey of the separate periods.

The problem of the dynamics of age flows directly from the problem of the structure of age which we just noted. As we have seen, the structure of age is not a static, unchangeable, immobile picture. At each given age, the structure formed previously makes a transition to a new structure. The new structure appears and is formed in the course of the development of the age level. The relation between the wholes and the parts, so essential to the concept of structure, is a dynamic relation that determines the change and development of the whole and its parts. For this reason, the dynamics of development must be understood as an aggregate of all the laws that determine the period of the appearance, change, and connecting of structural neoformations of each age level.

The very initial and essential point in the general determination of the dynamics of age is to understand that the relations between the personality of the child and his social environment at each age level are mobile.

One of the major impediments to the theoretical and practical study of child development is the incorrect solution of the problem of the environment and its role in the dynamics of age when the environment is considered as something outside with respect to the child, as a circumstance of development, as an aggregate of objective conditions existing without reference to the child and affecting him by the very fact of their existence. The understanding of the environment that developed in biology as applied to evolution of animal species must not be transferred to the teaching on child development.

We must admit that at the beginning of each age period, there develops a completely original, exclusive, single, and unique relation, specific to the given age, between the child and reality, mainly the social reality, that surrounds him. We call this relation the social situation of development at the given age. The social situation of development represents the initial moment for all dynamic changes that occur in development during the given period. It determines wholly and completely the forms and the path along which the child will acquire ever newer personality characteristics, drawing them from the social reality as from the basic source of development, the path along which the social becomes the individual. Thus, the first question we must answer in studying the dynamics of any age is to explain the social situation of development.

The social situation of development specific to each age determines strictly regulates the whole picture of the child’s life or his social existence. From this arises the second question which confronts us in the study of the dynamics of any age, specifically the question of the origin or genesis of central neoformations of the given age. Having elucidated the social situation of development that occurred before the beginning of any age, which was determined by relations between the child and his environment, we must immediately elucidate how, of necessity, neoformations proper to the given age arise and develop from the life of the child in this social situation. These neoformations that characterize the reconstruction of the conscious personality of the child in the first place are not a prerequisite but a result or product of development of the ago level. The change in the child’s consciousness arises on a certain base specific to the given age, the forms of his social existence. This is why maturation of neoformations never pertains to the beginning, but always to the end of the given age level.

Once the neoformations have appeared in the conscious personality of the child, they bring about a change in the personality itself, which cannot but have the most substantial influence on further development. If the preceding task in the study of the dynamics of age determined the path of the direct movement from the social existence of the child to a new structure of his consciousness, now the following task arises: finding a path of reverse movement from the changed structure of the child’s consciousness to a reconstruction of his existence. The child, having changed the structure of his personality, is already a different child whose social existence cannot but differ in a substantial way from the existence of the child of an earlier age.

Thus, the next question that confronts us in the study of the dynamics of age is the question of the consequences that result from the fact of the development of age-related neoformations. With concrete analysis, we can see that these consequences are so comprehensive and great that they encompass the whole life of the child. The new structure of consciousness acquired at a given age inevitably signifies a new character of perceptions of external reality and activity in it, a new character of the child’s perceiving his own internal life and the internal activity of his mental functions.

But to say this means at the same time to say something else also, which brings us directly to the last point that characterizes the dynamics of age. We see that as a result of the age-related development, the neoformations that arise toward the end of a given age lead to a reconstruction of the whole structure of the child’s consciousness and in this way change the whole system of relations to external reality and to himself. Toward the end of the given age, the child becomes a completely different being than he was at the beginning of the age. But this necessarily also means that the social situation of development which was established in basic traits toward the beginning of any age must also change since the social situation of development is nothing other than a system of relations between the child of a given age and social reality. And if the child changed in a radical way, it is inevitable that these relations must be reconstructed. The former situation of development disintegrates as the child develops and to the same extent, with his development, a new situation of development unfolds in basic traits, and this must become the initial point for the subsequent age. Research shows that this reconstruction of the social situation of development makes up the content of the critical ages.

Thus we come to elucidating the basic law of the dynamics of age levels. According to the law, the forces moving the child’s development at one age or another inevitably lead to rejection and disruption of the base of development of the whole age, with internal necessity determining the annulment of the social situation of development, the termination of the given period of development, and a transition to the following, or higher age level.

In a general outline, this is the scheme of age-related dynamic development.

3. The Problem of Age and the Dynamics of Development

The problem of age level is not only central to all of child psychology, but is also the key to all the problems of practice. This problem is directly and closely connected with the diagnostics of age-related development of the child. Systems of research devices that are intended to determine the actual level of development attained by the child are usually called diagnostics. The actual level of development is determined by that age, that stage or phase within a given age that the child is experiencing at the time. We already know that the child’s chronological age cannot serve as a reliable criterion for establishing the actual level of his development. For this reason, the determination of the actual level of development always requires special study which serves to establish a diagnosis of development.

Determining the actual level of development is the most essential and indispensable task in resolving every practical problem of teaching and educating the child, checking the normal course of his physical and mental development, or establishing disturbances of one kind or another in development that upset the normal course and make the whole process atypical, anomalous, and in some cases pathological. Thus, the determination of the actual level of development is the first and basic task of the diagnostics of development.

The study of symptomatology of age levels in children is a basis for identifying a number of reliable traits which can be used to determine the phase and stage of each age of the process of the child’s development just as a doctor diagnoses an illness on the basis of one set of symptoms or another, that is, identifies the internal pathological process that is manifested in the symptoms.

In itself the study of some age symptom or group of symptoms and even precise quantitative measuring of these still cannot be a diagnosis. Gesell said that there is a great difference between measuring and diagnosis. It consists in the fact that we can make a diagnosis only if we are able to disclose the sense and significance of the symptoms found.

The tasks confronting the diagnostics of development may be resolved only on the basis of a profound and broad study of the whole sequence of the course of child development, of all the features of each age, stage, and phase, of all the basic types of normal and anomalous development, of the whole structure and dynamics of child development in its many forms. Thus, in itself, determining the actual level of development and quantitative expression of the difference between chronological and standardized age of the child or the relation between them expressed in a coefficient of development is only the first step along the way toward diagnostics of development. In essence, determining the actual level of development not only does not cover the whole picture of development, but very frequently encompasses only an insignificant part of it. In establishing the presence of one set of symptoms or another in determining the actual level of development, we actually determine only that part of the total picture of development of the processes, functions, and properties that have matured by that time. For example, we determine growth, weight, and other indicators of physical development that are characteristic of an already completed cycle of development. This is the outcome, the result, the final attainment of development for the period passed. These symptoms indicate rather how development occurred in the past, how it was concluded in the present, and what direction it will take in the future.

It is understood that knowing the outcome of yesterday’s development is a necessary point for making a judgment on development in the present and in the future. But this alone is certainly not enough. Figuratively speaking, in determining the actual level of development, we determine only the fruits of development, that is, that which has already matured and completed its cycle. But we know that the basic law of development is that different aspects of the personality and its different properties mature at different times. While some processes of development have already borne fruit and concluded their cycles, other processes are only at the stage of maturation. A genuine diagnosis of development must be able to catch not only concluded cycles of development, not only the fruits, but also those processes that are in the period of maturation. Like a gardener who in appraising species for yield would proceed incorrectly if he considered only the ripe fruit in the orchard and did not know how to evaluate the condition of the trees that had not yet produced mature fruit, the psychologist who is limited to ascertaining what has matured, leaving what is maturing aside, will never be able to obtain any kind of true and complete representation of the internal state of the whole development and, consequently, will not be able to make the transition from symptomatic to clinical diagnosis.

Ascertaining the processes that have not matured at the time, but are in the period of maturation is the second task of the diagnostics of development. This task is accomplished by finding the zones of proximal development. We will explain this concept, most important from both the theoretical and practical aspect, using a specific example.

In psychology, to determine the actual level of the child’s intellectual development, most of the time a method is used in which the child is asked to solve a number of problems of increasing difficulty and standardized for the child’s chronological age level. The study always determines the level of difficulty of the problems that the given child can solve and the standard age corresponding to it. The mental age of the child is determined in this way. It is assumed that independent solving of the problems only and exclusively is indicative of the mind. If in the course of solving a problem, the child is asked a leading question or given a direction as to how to solve the problem, such a solution is not accepted in determining mental age.

The basis for this idea is the conviction that non-independent solving of the problem is devoid of significance for judging the mind of the child. Actually, this conviction distinctly contradicts all the data of contemporary psychology. It was based on the old, incorrect, and now completely discredited idea that imitating any kind of intellectual operation may be a purely mechanical, automatic act that says nothing about the mind of the imitator. The incorrectness of this view was initially exposed in animal psychology. In his famous experiments with humanlike apes, W Köhler established the remarkable fact that animals can imitate only such intellectual actions as lie within the zone of their capabilities. Thus, the chimpanzee can reproduce sensible and purposeful action that it is shown only if this operation relates in type and degree of difficulty to the same category as do sensible and purposeful activities that the animal can do independently. The animal’s imitation is strictly limited by the narrow boundaries of its capabilities. The animal can imitate only that which it is capable of doing.

With the child, the situation is much more complex. On the one hand, at different stages of development, the child may imitate far from everything. His capability for imitation in the intellectual sphere is strictly limited by the level of his mental development and his age-related potentials. However, the general law is that unlike the animal, the child can enter into imitation through intellectual actions more or less far beyond what he is capable of in independent mental and purposeful actions or intellectual operations. This difference between the child and the animal can be explained by the fact that the animal cannot be taught in the sense in which we apply this word to the child. The animal is adaptable only to dressage [trained response to signals]. It can only develop new habits. By exercise and combination, it can perfect its intellect, but is not capable of mental development, in the true sense of the word, through instruction. This is why all experimental attempts using instruction to develop in higher animals new intellectual functions not proper to them but specific to man inevitably meet with failure, as did the attempt of R. Yerkes to graft human speech into ape offspring or the attempts of E. Tolman to train and instruct chimpanzee offspring together with human children.

Thus we see that, aided by imitation, the child can always do more in the intellectual sphere than he is capable of doing independently. At the same time, we see that his capability for intellectual imitation is not limitless, but changes absolutely regularly corresponding to the course of his mental development so that at each age level, there is for the child a specific zone of intellectual imitation connected with the actual level of development.

Speaking of imitation, we do not have in mind mechanical, automatic, thoughtless imitation but sensible imitation based on understanding the imitative carrying out of some intellectual operation. In this respect, on the one hand, we restrict the meaning of the term, using it only in the sphere of operations that are more or less directly connected with mental activity of the child. On the other hand, we extend the meaning of the term, applying the word “imitation” to all kinds of activity of a certain type carried out by the child not independently, but in cooperation with adults or with another child. Everything that the child cannot do independently, but which he can be taught or which he can do with direction or cooperation or with the help of leading questions, we will include in the sphere of imitation.

With this kind of definition of this concept we can establish the symptomatic significance of intellectual imitation in the diagnosis of mental development. What the child can do himself, with no help on the side, reveals his already mature capabilities and functions. These are the ones that are established with tests usually used for determining the actual level of mental development since the tests are based exclusively on independent problem solving.

As we have said, it is always important to ascertain not only the mature processes but also those that are maturing. With respect to the child’s mental development, we can solve this problem by determining what the child is capable of in intellectual imitation if we understand this term as defined above. Research shows a strict genetic pattern between what a child is able to imitate and his mental development. What the child can do today in cooperation and with guidance, tomorrow he will be able to do independently. This means that by ascertaining the child’s potentials when he works in cooperation, we ascertain in this way the area of maturing intellectual functions that in the near stage of development must bear fruit and, consequently, be transferred to the level of actual mental development of the child. Thus, in studying what the child is capable of doing independently, we study yesterday’s development. Studying what the child is capable of doing cooperatively, we ascertain tomorrow’s development.

The area of immature, but maturing processes makes up the child’s zone of proximal development.

Using an example, we shall elucidate how the zone of proximal development is determined. Let us assume that as a result of a study, we established that two children are the same in age and mental development. Let us say that both are eight years old. This means that both independently solve problems of the level of difficulty that corresponds to the standard for age eight. In this way, we determine the actual level of their mental development. But we continue the study. Using special devices, we test to what extent both children are able to solve problems that are beyond the standard for age eight. We show the child how such a problem must be solved and watch to see if he can do the problem by imitating the demonstration. Or we begin to solve the problem and ask the child to finish it. Or we propose that the child solve the problem that is beyond his mental age by cooperating with another, more developed child or, finally, we explain to the child the principle of solving the problem, ask leading questions, analyze the problem for him, etc. In brief, we ask the child to solve problems that are beyond the limits of his mental age with some kind of cooperation and determine how far the potential for intellectual cooperation can be stretched for the given child and how far it goes beyond his mental age.

It develops that one child solves problems cooperatively that standards relate to, let us say, age twelve. The zone of proximal development moves his mental age forward by four years. The other child moves forward with cooperation only to the standard age level of a nine-year-old. His zone of proximal development is only one year.

Are these children identical in age according to the actual level of development attained? Obviously their similarity is limited to the area of already mature functions. But with respect to maturing processes, one went four times further than the other.

We explained the principle of immature processes and properties with the example of the mental development of the child.

It is completely understandable that in determining the physical development of the child, the method of study which we have just described with respect to intellectual development is completely inapplicable. But in principle, the problem pertains to this aspect of development as it does to all others in completely the same way. It is important for us to know not only the child’s already attained limits of growth and of the other processes of which his physical development consists, but also the progress of the process of maturation itself which will be evident in later development.

We will not stop to consider determination of the zone of proximal development that applies to other aspects of the child’s personality. We shall elucidate only the theoretical and practical significance of this determination.

The theoretical significance of this diagnostic principle consists in that it allows us to penetrate into the internal causal-dynamic and genetic connections that determine the process itself of mental development. As has been said, the social environment is the source for the appearance of all specific human properties of the personality gradually acquired by the child or the source of social development of the child which is concluded in the process of actual interaction of “ideal” and present forms.

A closer source of the development of internal individual properties of the child’s personality is cooperation (this word understood in the broadest sense) with other people. Thus, by applying the principle of cooperation for establishing the zone of proximal development, we make it possible to study directly what determines most precisely the mental maturation that must be realized in the proximal and subsequent periods of his stage of development.

The practical significance of this diagnostic principle is connected with the problem of teaching. A detailed explanation of this problem will be given in one of the closing chapters. Now we consider only the most important and initial moment. We know that there are optimum times in the child’s development for each type of teaching. This means that teaching a given subject, given information, habits, and skills is easiest, efficient, and productive only at certain age periods. This circumstance has for a long time dropped out of sight. The lower boundary for optimum times for teaching was established earliest. We know that an infant of four months cannot be taught to speak, or a two-year-old be taught to read and write, because at those times, the child is not mature enough for such teaching; this means that the child has not yet developed those properties and functions that are prerequisites for this kind of teaching. But if only the lower limit existed for the potential for teaching at a certain age, we could expect that the later the respective teaching begins, the more easily it will be conveyed to the child and will thus be more productive because at a later age, there will be a greater degree of maturity of the prerequisites needed for the teaching.

Actually, this is not true. The child beginning to learn to speak at three years and to read and to write at twelve, that is, somewhat late, also seems to be in unfavorable conditions. Teaching that is a little late is also difficult and unproductive for the child, just like that which is a little too early. Obviously, there is also an upper threshold of optimum times for teaching from the point of view of the child’s development.

How can we explain the fact that a three-year-old child in whom we find a great maturity of attention, alertness, motor ability, and other properties that are necessary prerequisites for learning speech, acquires speech with more difficulty and with less advantage than a child of a year and a half in whom these same prerequisites are undoubtedly less mature? Obviously the reason for this is that teaching is based not so much on already mature functions and properties of the child as on maturating functions. The period of maturation corresponding to the functions is the most favorable or optimum period for the corresponding type of teaching. It is also understandable, if we take this circumstance into account, that the child develops through the very process of learning and does not conclude the cycle of development. First the teacher teaches the pupil not what the child can already do independently, but what he still cannot do alone, but can do with the help of teaching and guidance. The process of teaching itself is always done in the form of the child’s cooperation with adults and represents a partial case of the interaction of the ideal and the present form, of which we spoke above, as one of the most general laws of social development of the child.

In greater detail and more concretely, the problem of the relation between teaching and development will be presented in one of the last chapters dealing with school age and with teaching in school. But now it must be clear to us that since teaching depends on immature, but maturing processes and the whole area of these processes is encompassed by the zone of proximal development of the child, the optimum time for teaching both the group and each individual child is established at each age by the zone of their proximal development.

This is why determining the zone of proximal development has such great practical significance.

Determining the actual level of development and the zone of proximal development also comprises what is called normative age-level diagnostics. With the help of age norms or standards, this is meant to elucidate the given state of development characterized from the aspect of both the finished and the unfinished processes. In contrast to symptomatic diagnostics depending only on establishing external traits, diagnostics that attempts to determine the internal state of development that is disclosed by those traits is called clinical diagnostics in analogy to medical studies.

The general principle of all scientific diagnostics of development is the transition from symptomatic diagnostics based on the study of symptom complexes of child development, that is, its traits, to clinical diagnostics based on determining the internal course of the process of development itself Gesell believes that normative data must not be applied mechanically or purely psychometrically, that we must not only measure the child, we must interpret him. Measurement, determination, and comparison to standards of symptoms of development must appear only as a means for formulating the diagnosis of development. Gesell writes that diagnosis of development must not consist only of obtaining a series of data by means of tests and measurements. Diagnostics of development is a form of comparative study using objective norms as points of departure. It is not only synthetic, but analytical as well.

The data from testing and measuring make up the objective basis for a comparative evaluation. The patterns of development yield standards of development.

But the diagnosis in the true sense of this word must be based on a critical and careful interpretation of the data obtained from various sources. It is based on all the manifestations and facts of maturation. The synthetic, dynamic picture of these manifestations, the aggregate of which we call personality, enters as a whole into the framework of the study. We cannot, of course, precisely measure the traits of personality. We can only with difficulty determine what we call personality, but from the point of view of diagnostics of development, as Gesell assumes, we must observe how personality is made up and matures.

If we limit ourselves only to determining and measuring symptoms of development, we will never be able to go beyond the limits of a purely empirical establishment of what is obvious to persons who just observe the child. In the best case, we will be able only to increase precision of the symptoms and confirm them with measurement. But we can never explain the phenomena we observe in the development of the child nor predict the further course of development, nor indicate what kind of measures of a practical nature must be applied with respect to the child. Ibis kind of diagnosis of development, fruitless with respect to explanation, prognosis, and practical applications can be compared only to those medical diagnoses that doctors made at the time when symptomatic medicine prevailed. The patient complains of a cough, the doctor makes a diagnosis: the illness is a cough. The patient complains of a headache, the doctor makes a diagnosis: the illness is a headache. This kind of diagnosis is essentially empty since the investigator adds nothing new to what he knew from observations of the patient himself and plays back to the patient his own complaints, supplying them with scientific labels. The empty diagnosis cannot explain the observed phenomena, can predict nothing relative to their fate and cannot give practical advice. A true diagnosis must provide an explanation, prediction, and scientific basis for practical prescription.

The matter is precisely the same with respect to symptomatic diagnosis in psychology. If a child is brought in for consultation with complaints that he is developing poorly mentally, has a poor imagination and is forgetful, if after investigation, the psychologist makes the diagnosis: the child has a low intelligence quotient and mental retardation, the psychologist also explains nothing, predicts nothing, and cannot help in any practical way, like the doctor who makes the diagnosis: the illness is a cough.

It can be said with no exaggeration that definitely practical measures on safeguarding the development of the child, his teaching and education, since they are connected with the features of one age or another, necessarily require diagnostics of development. The application of diagnostics of development to solving endless and infinitely varied practical problems is determined in each concrete case by the degree of scientific development of the diagnostics of development and the demands that confront it in the resolution of each concrete practical problem?