The science of human anatomy is the study of the form and structure of the human body (and the organs and systems which form it) and the regulari ties of the development of this structure in relation to its functions and exter nal environment. At the base of this science in the Soviet Union lies the advanced philosophy of dialectical materialism. The study of anatomy previously dealt with a single problem: how the body is built. Descriptive anatomy, so called because it was restricted to a description of the body's structures, studied the body's form without regard to its function and made no attempt to disclose the laws governing its develop ment. The approach taken by descriptive anatomy was thus metaphysical.1 Any science, however, undergoes two phases during its development: a descriptive phase during which facts are accumulated and described and a synthetic phase in which the accumulated facts are generalized and system atized and recurring patterns disclosed. The science of modern anatomy, therefore, seeks not only to describe but to generalize the facts, to uncover the regularities governing the structure and development of the human body and to regulate that structure, its organs, and its systems.

The object of the old descriptive anatomy was description of the struc ture of the body. In modern anatomy, however, description is a means rather than an end, one of the methods used in studying the human body structure. This method gives modern anatomy its descriptive aspect. Modern anatomy, however, attempts to explain not only how the organism is formed, but why it is so formed. To answer this second question, it is necessary to investigate both internal and external relationships of the organism.
According to dialectics (in contrast to metaphysics), everything in nature is interrelated, just as the living human organism is an integral sys tem. For this reason, anatomy studies the organism not simply as the sum of its parts independent of the environment but as a discrete unit subject to and in unity with external conditions of existence. Dialectics, as opposed to metaphysics, further teaches that everything in nature changes and develops. Similarly, the human organism is not an unalterable entity cast in a single, unvariable shape but changes continuously from the time of birth to the moment of death. The human species, in addition, is the product of pro longed evolution and displays features resembling those of the lower animal forms. Anatomy, therefore, studies not only the structure of the modern adult human being, but investigates the human organism in its historical develop ment. With this in mind, the following three points should be consid ered. The development of the human genus in relation to the evolutiona ry process of the lower life forms. This study is called phylogenesis (Gk phylort genus, genesis development) and uses the data of comparative anatomy, which compares the structures of various animals and man. In addition to compara tive anatomy, which is a descriptive science, phylogenesis takes into account the principles of evolutionary morphology. Evolutionary morphology studies the dynamic forces of evolution and the structural changes an organism undergoes in its adaptation to given conditions in the environment (A. N. Se-vertsev). The formation and development of the human being in relation to the development of society. The study of anthropogenesis (Gk anthropos hu man being), which uses the findings of both comparative anatomy and evolu tionary morphology, is based primarily on the data of anthropology, the scientific study of mankind in its development. A branch of anthropology known as anatomical anthropology studies the structure of the human body not in relation to a hypothetical "average" human being but in relation to a given group of people who may vary according to constitution, occupation, and way of life. Anthropology studies man's evolution and physical make up taking into account the historical development of the specific social group to which he belongs. In addition, anthropology is concerned with specific structural features of the human body as they relate to anthropogenesis and the leading role of labour in this process.
The process of the development of the individual organism through out life. Ontogenesis (Gk onthos being) is concerned with uterine, embryonal (embryogenesis) processes, and extrauterine, postembryonal or postnatal (L post after, natus birth) processes. The data of embryology (Gk embryo to grow) and age anatomy are used in the study of ontogenesis. The last period of ontogenesis, ageing, is the subject of gerontology, the study of the ageing process (Gk geron, gerontos old man). Individual and sexual differences in the shape, structure, and position of the body and its organs as well as the topo graphic relationships of the organs are also taken into account.
As a result, the study of anatomy treats the human organism as a single entity, subject to definite patterns of development which have been influenced by various internal and external conditions throughout the evolutionary process. This approach to the structure of the human organism gives anatomy its evolutionary aspect. Dialectical materialism also teaches that form and content or form and function are unified and each is determined by the other. An organism con tains no structure that is not engaged in some function, and there are no functions that cannot be associated with some structure. 'The whole of or ganic nature is one continuous proof of the identity or inseparability of form and content'1 (function—M.P.). Each organ is to a great degree the product of the work in which it is engaged. The study of anatomy thus has a function al aspect since the structure of the organism and its separate parts and organs are considered inseparable from the function each body part performs.
The study of human anatomy is conducted not simply in and of itself. It is rather based on the principle of the unity of theory and practice and has an applied aspect which serves both medical science and physical cul ture.
The descriptive, evolutionary, and functional aspects of the study of anatomy are different features of a single science. The most important feature of the Soviet study of anatomy is its effectiveness, its attempt not to contem plate and describe the structure of the body passively (as advocated by Feuerbach's contemplative materialism) but to discover the natural laws governing the structure and development of the organism and to master these laws and thus influence the human organism in the direction necessary for the favourable and harmonious development of man. L. Feuerbach argued that it is sufficient to observe nature, to contem plate it passively without interfering with it. Criticizing Feuerbach in "Theses on Feuerbach" Marx wrote: "The philosophers have only interpreted the world in various ways; the point is to change it."2
Science, according to Marx, must therefore serve three purposes: de scription, explanation, and direction. Anatomy, as a science, accumulates and describes facts. Its evolutiona ry and functional aspects provide the possibility for explaining these facts and for determining the regular features of the human body structure. With a practical orientation, the science of anatomy may master and, in turn, direct and control these features. Anatomy may thus solve the problems of description, explanation and direction, and is consequently a science with considerable prospects.
In view of the vast material involved and the difficulty of studying the organism as a single entity, it is at first examined according to systems. The approach of systematic anatomy is to divide the organism artificially into parts using the analytical method. In the living organism, however, the sepa­rate parts and components of the body's structure (its systems, organs, tissues and so on) are not isolated but related in origin and development, and each helps shape and form the others.
To understand the organism as an entity, therefore, the synthetic meth od must also be applied. Anatomical knowledge is synthesized throughout the anatomy course by disclosing the connection between form and function and by studying the structure as its development is influenced by external and internal factors. At the end of the course, the body's systems are studied together, as they exist in the living organism. Attention is focused on the relationship of each system to every other and especially to the nervous system, which unites the organism into a single entity (see the chapter "Synthe­sis of Anatomical Data"). Besides systematic anatomy there is topographic or regional anatomy which studies the spatial relationships of the organs in the different body regions. Since topographic anatomy has direct, practical significance for clinical work, particularly in surgical practice, it is also called surgical ana tomy. Some authors separate from topographic anatomy an aggregate of information concerning the external relief of the body and its regions under the term "relief anatomy.
Sport anatomy studies the structure of the organism of individuals engaged in sports and the effect produced on the body's structure by various sports. Taught at institutes of physical culture, sport anatomy contributes to the improvement of the training of athletes. Sport anatomy is a branch of anatomical anthropology, which is concerned with the study of the anatomy of people with differing traits (race, constitution, habitat, and so forth).
Special attention is focused at institutes of physical culture on the functional anatomy of the supportive and motor apparatus. This branch of anatomy studies not only the structure of the apparatus but its dynamics, and is therefore called dynamic anatomy. Applied anatomy for artists and sculptors studies only the external form and proportions of the body and is known as plastic anatomy. Anatomy that studies the normal healthy organism is called normal anatomy, as distinct from pathological, or morbid, anatomy, which is con cerned with the study of the sick organism and the morbid changes in its organs.
The types of anatomy indicated above differ in their approach to the study of the human body, which may be conducted on a cadaver or on a living person. Study of the anatomy of the living human being is especially necessary for the physician. The successes of this branch of anatomy are linked with advances in X-ray methods of examination which allow physicians to view almost all the organs and systems of the living human organism and consti tute an integral part of that branch of modern anatomy designated as X-ray anatomy.
All these branches of anatomical science are different aspects of a single human anatomy.
The relationships existing in a single organism can be understood only by comparing the anatomical data with the data of other, related discip lines.
Man is the high point in the development of living matter. To understand the human structure, therefore, it is necessary to use the data of biology, the science of the laws of the origin and development of living matter. Just as man is a part of nature, anatomy, the science studying man's structure, is part of biology. Man, however, is an animal who produces tools. This classical definition voiced by B. Franklin and accepted by K. Marx reflects two aspects of man's nature: biological ("man is an animal..."), indicating man's relationship to the animal world, and social ("... producing tools"), emphasizing his social nature. The great importance of social conditions in man's development must consequently be borne in mind. The study of human aimtomy, therefore, exceeds the realms of biology and merges with the social sciences. The unity of form and function in the structure of the organism. The organism and its components—organs, tissues, and cells—are different types of matter.
Dialectical materialism teaches that matter exists by movement and continuous change in space and time. From this point of view, form character izes the arrangement of moving matter in space, that is the organization of the morphological substrate, whereas function is the process of its change in time. Because space and time, as properties of moving matter, are insepara ble, form and function are interconnected and unified.
In this way the structure of living matter is a combination of the mor phological substrate (or matter) and the dynamics of its changes (or move ment). The structure of living matter, thus, comprises not only the form but the function, not only the morphological but the functional peculiarities of the organism.
To understand the structure of the organism in light of the connection between form and function, anatomy uses the data of physiology, the science of the organism's vital functions. Biology is usually separated into two branches: morphology, the study of form, and physiology, the study of function. Such separation is conditional, however, because "morphological and physio logical phenomena, form and function, mutually determine one another."1 Anatomy and physiology study one and the same object, the structure of living matter, but from different standpoints: anatomy from the standpoint of the form and organization of living matter and physiology from that of function, the processes taking place in the living matter. Thus anatomy and physiology, the alpha and omega of medical knowledge, are closely related disciplines. As A. P. Valter, a Russian anatomist and physiologist of the 19th century justly noted, "anatomy in union with physiology is the tsarina of medicine".
Since the external shape of organs cannot be separated from their internal structure, anatomy is also related closely to histology, the science of tissues, particularly to the branch of histology known as microscopic anatomy. Macroscopic, or gross, anatomy (Gk markos large, skopein to watch) and microscopic (Gk mikros small) anatomy are in essence a single science divided into two branches according to examination technique. Because of the specific character of the examination methods (microscope), the vast amount of material to be examined, and the specific patterns governing the develop ment of tissues, cells, and extracellular substance, however, histology (Gk histos tissue) and cytology, the science of the cell (Gk kytos cell), are con sidered independent branches of science.
With the invention of the electron microscope, it became possible to examine submicroscopic structures and even molecules of living matter, which are also the objects of study in chemistry. A new science, cytochemistry, was born at the junction of cytology and chemistry. As a result the structure of the human organism is now studied at different levels:
At the level of systems and organs: (a) with the naked eye—macro scopic, or gross, anatomy; (b) with a magnifying glass—micro-macroscopic anatomy; (c) with a microscope—microscopic anatomy.
At the level of tissues (histology): (a) with a magnifying glass; (b) with a microscope.
At the cellular level (cytology): (a) with a light microscope; (b) with an electron microscope.
At the molecular level: (a) with an electron microscope and by means of cyto-histochemical reactions.
Thus, anatomy and histology are currently divided according to level and technique of examination.
Anatomy, histology, cytology, and embryology constitute the gener al science of the form, structure, and development of the organism, which is called morphology (Gk morphe form, shape).


METHODS OF ANATOMICAL STUDY
There are two principal methods of anatomical study.
Examination of a cadaver by opening the body cavities and dissecting the organs and tissues with surgical instruments. The science of anatomy derives its name from this procedure of dissecting the whole cadaver into parts (Gk anatome to dissect). Tubular systems (vessels, ducts, and so forth) are injected with various media (injection method) and then exposed to X-rays, clarification, or corrosion. Nerves are treated by elective staining.
Examination of a living human being. Every physician begins examination of a patient with this procedure, which includes palpation, percussion, auscultation, various measurements of the body (anthropometry), and endoscopy examination of the hollow organs through the natural body orifices (Gk endon within).
X-rays provide the best possibilities for studying "living anatomy". They open, as it were, the internal organs of a living human being without a knife and without pain and make it possible to observe the structure of the organs of a single individual throughout the course of his life (X-ray anatomy). X-rays are used for making X-ray photographs (radiography) and for visualization on a special screen (radioscopy). The newest methods of X-ray examination are as follows:
Electroradiography produces an X-ray image of the soft tissues (skin, subcuta neous fat, ligaments, cartilages, the connective tissue framework of the parenchymatous organs, etc.) which are invisible on ordinary radiographs because they are radiolucent.
Computer tomography produces an image of all the organs in a single plane of body tissue, much like sections of a frozen cadaver prepared according to the method developed by N. I. Pirogoff.
The living human being should be the main object of study in anatomy, with ex amination of cadavers providing supplementary information (P. F. Lesgaft). But because modern technology is still unable to supply the means for a profound study of the living human body, cadaver dissection remains the most important method of anatomical study.
In addition, experimental anatomy, in which experiments are performed on animals, is an important method of anatomical research.
As can be seen, modern anatomy has at its disposal a rich store of means for studying the structure of both the dead and the living human body.