Internal Diseases

INTERNAL DISEASES, one of the largest branches of theoretical and practical medicine, a scientific discipline whose task is the study of the diagnosis of diseases of internal organs in their various clinical forms, the causes of their origin, both exogenous and endogenous, their pathogenesis, prevention and therapy. Internal diseases, as a separate specialty, require from the physician broad medical thinking that evaluates a disease of an internal organ only in an inseparable connection with the entire organism as a single psycho-physical whole. The causal dependence of most diseases of internal organs on the harmful influence of the external environment: nutrition, housing, occupational hazards, etc., requires from the internist the ability to take into account not only the domestic and etiological factors causing the disease, but more often also the social prerequisites for diseases of internal organs. Medical thinking, which underlies both the theoretical development of internal diseases and the practical activity of the internist, fully and vividly reflects the most important stages in the history of medicine, the main and essential part of which is internal diseases. Internal diseases, based on the study of anatomy, physiology, general pathology, bacteriology, pharmacology and clinical medicine, have historically always constituted a larger part of the curriculum of medical schools. Not surprisingly, that even in our days, in contrast to other specialties, the clinic of internal diseases, for example, in German universities, is called "Medizinische Klinik", and in France - "Clinique medicale" (Medical clinic); this has deep roots in the historical development of internal diseases. Internal medicine, having in mind its highest task - the study of diseases of the human organism, over thousands of years has developed for physicians guiding ideas about the origin, essence and treatment of diseases, often in accordance with the philosophical doctrine prevailing in a given era. Although other branches of medicine (surgery, obstetrics, ophthalmology) are no less, if not more, ancient in origin, they have historically for many centuries retained only a purely practical character, leaving the theoretical development of questions about the essence of disease to internists. In Prussia, for example, surgeons were only recognized by law as equal physicians in 1852, and only from then on was it required that they have theoretical training on a par with physicians studying medicine as a science. Over the last 100 years, a number of major new disciplines have emerged from the vast field of internal diseases. Thus, at the beginning of the 19th century in Vienna, the study of skin diseases begins, and in 1841, Skoda transfers part of the internal diseases clinic to Hebra, where dermatology grew; in France, the famous internist Charcot isolates neurology as a separate discipline; finally, pediatrics separates from internal diseases as a completely separate branch. The rapid growth of bacteriology and the doctrine of immunity, in connection with the pronounced character of a number of diseases as social diseases, has led to the isolation of separate disciplines of infectious diseases and tuberculosis, which always occupy such a prominent place in the practical work of every internist. In addition, by the end of the first quarter of the 20th century, as a result of the significant development of medical sciences and brilliant technical achievements, it became necessary to specially develop already individual parts of internal diseases, and the expression of this specialization is the organization of special clinics and institutes for the study, for example, of diseases of the heart and blood vessels, diseases of digestion and metabolism, not to mention the growth of scientific research institutes for the study of tuberculosis, malaria and syphilis, endocrinology, uniting the work of numerous specialists and already having extensive literature, specialized journals and congresses. How this process of specialization will affect the development of the entire doctrine of internal diseases, on the one hand, and on the thinking and practical activity of the internist, on the other, can only be judged in the perspective of the historical process of development of medical ideas. Based on socio-economic prerequisites and essentially determined by the development of political and social life in a given country, medicine, and with it the doctrine of internal diseases, developed and flourished in different eras in different states in close connection with the growth of the economy and culture of a given people. It is easy to trace that in the character of the theoretical study of internal diseases, and even more so in their practical application, the religious trends, trade connections, economic and class relations of a given era and country are most vividly reflected. However, three circumstances, as is known, have always played a particularly significant role in the history of internal diseases: the philosophical ideas prevailing in a given era, which determined the movement of scientific medical thought in general; the successes of the exact natural sciences, especially physics and chemistry, and the associated discoveries and achievements of technology, and finally, what was especially important for internal medicine, the medical thinking of representatives of the largest medical schools (see History of Medicine, Homeopathy). The most essential stages and milestones that have a direct genetic connection with the modern state of the doctrine of internal diseases are as follows: the development of the natural sciences and the great discoveries of the 19th century placed internal medicine for the first time since Bichard on a solid basis of observation, analysis and experiment and gave the internist powerful methods for recognizing and treating internal diseases, based on the achievements of the exact sciences. The doctrine of internal diseases has since placed more and more emphasis on the exact study of the healthy and sick person on the basis of modern scientific understanding and sees in the clinic of internal diseases a pure science, an inexhaustible source for the study of scientific medical facts. Ditl, a student of the most prominent representative of this school, Rokitansky (1804-78) in Vienna, says: "The last hour of groundless empiricism has already struck; only what has a strictly scientific, natural-historical justification should be transferred to practical medicine; everything else belongs to the realm of mysticism. Our predecessors were interested in the results of treatment, we are interested in the result of our research. The physician should be only a naturalist, but not a representative of the healing art. Medicine is a science, not an art; in knowledge, not in our practical activity, lies our strength." This trend bases the study of the disease, mainly, on objective methods, treating this study as a phenomenon of nature, subordinating it to the existing natural-historical dogma and methodology, and found its most vivid expression in the words of one of the greatest internists of our time, Naunin, who believed that "internal medicine will be an exact natural science or it (internal medicine) will not exist at all." This deep faith in the necessity and possibility to build the medical thinking of the internist only on the principles of the objective scientific method, on the principles of an exact science, was among internists a direct and legitimate consequence of the proud consciousness of the greatest successes of anatomy, physiology, pathology and clinical medicine, achieved by the introduction of pathological anatomy and the experimental method into the study of internal diseases. It is difficult, of course, to assess all the successes of the doctrine of internal diseases as a result of the application in the clinic of the methodology of the exact sciences, especially if one takes into account the greatest achievements of technology in the last 50 years, achievements that open up unlimited prospects for the study of the healthy and sick person. And even the founders of pathological anatomy - Morgagni and Virchow - and of the experimental method - Claude Bernard - could hardly have dreamed of the possibilities that modern technology gives into the hands of the physician for studying the disease and methods of therapeutic intervention on it. At the same time, on the soil of natural-historical thinking, various trends have arisen in the doctrine of internal diseases, which have had an enormous influence on the thinking of internists and their practical work. One should keep in mind, above all, the significance of humoral and cellular pathology for the development of the doctrine of internal diseases. Despite the contradictions of medical schools of all times and the change of various medical systems, the understanding of the essence of disease has always come down from ancient times to the doctrine of the improper mixing of the basic fluids of the human organism, to the doctrine of dyscrasias, to the humoral understanding of the essence of diseases. When Theophrastus Paracelsus proved the chemical unsuitability of the four humors, only mystical, metaphysical systems could replace the humoral doctrines for three whole centuries, surrendering medicine to the most unbridled subjectivism of their authors. Therefore, the beginning of the naturalistic era should be considered only the doctrine of the Italian Giovanni Battista Morgagni (1682-1771), who left us 5 books "De sedibus et causis morborum" and placed in the first place the question of the location of the disease: -Ubi est morbus? (Where is the disease?). The investigation of sedes morbi leads from the study of the organ to the study of tissue, from tissues to cells, from humoral pathology to solid pathology, to cellular pathology. Virchow's cellular pathology, which placed the material substrate at the head of naturalistic medical thinking, was the justification for the morphological approach in the understanding of internal diseases and led to the detailed study of anatomical changes of individual organs in various diseases.

"I assert," says Virchow, "that no physician can think correctly about a pathological process if he cannot indicate its location in the body." This localist approach of the Virchow school dominated the clinic of internal diseases in the second half of the 19th century and was carried significantly beyond the limits set by the theory itself by its followers. Virchow's doctrine laid a solid foundation for the study of the material substrate of diseases, deepening the understanding of the smallest changes in the cell and individual organ in a given internal disease. This morphological approach gave exceptionally fruitful results for the clinic of internal diseases and for many of them, it seemed to finally resolve the question not only of sedes morbi but also of the very essence of the disease. The localist view of disease undoubtedly contributed much to the development of internal medicine, but on the other hand, it firmly fixed the physician's attention on the static of the pathological process to the detriment of the biological understanding of disease as a dynamic phenomenon. In therapy, this morphological, localist approach led to the desire to influence sedes morbi, the diseased organ, to the search for therapeutic agents that affect not the very essence of the disease or the entire organism, but only the cells of the diseased organ. In connection with the successes of physics, chemistry, and industry, the second half of the 19th century is characterized by the rampant growth of the pharmaceutical industry and drug therapy, and almost completely forgotten are not only the distracting methods of treatment, bloodletting and other therapeutic measures affecting the entire organism, but also recedes to the background treatment by the healing powers of nature—physiotherapy, which the school of Hippocrates attached such great importance to. The localist method of medical thinking could not, obviously, find sufficient scientific morphological justification for therapeutic methods affecting the entire organism and not the diseased organ, sedes morbi, and therefore rejects them. The impossibility of finding a morphological substrate for the action of many drugs and therapeutic measures led to a very restrained attitude of many prominent clinicians toward questions of therapy, an attitude often bordering on therapeutic nihilism. For representatives of localist, organoid, cellular pathology, there are no diseases without local localization, and even the very posing of the question about diseases common to the entire organism is absurd to them (Virchow). Parallel to and almost simultaneously with Virchow's theory, another worldview was being created in France, which had exceptional significance in the development of the doctrine of internal diseases. Claude Bernard says: "Medicine must not tie itself to any system, whether vitalistic, animistic, organic, or humoral; it can only be a science that seeks to reduce all manifestations of life in healthy and diseased states to their nearest causes. One must strive to break the fetters of philosophical and scientific systems, as we break the chains of intellectual slavery. Systems only enslave the human spirit." The founder of the experimental method, Claude Bernard, says: "Le medecin experimentateur est le medecin d'avenir" (the experimenter physician is the physician of the future). Claude Bernard ascribes absolute value to the experimental method in the clinic and believes that only pathophysiology, as an experiment on the sick person, opens to the physician the essence of disease and the paths to combat it. Thus, instead of the question of sedes morbi, the old question of the cause and essence of disease is again placed in the first place, and experiment is destined to bring complete clarity to the thinking of the internist. The brilliant discoveries of Claude Bernard, which were the result of the experimental method (let us only mention the discovery of glycogen, the glycogenic function of the liver, and the "sugar" injection), for a long time predetermined the dominance of the experimental method in the clinic and fixed the attention of physicians on the dynamics of the pathological process, which the new experimental method promised to reveal. This, beyond any doubt, is the greatest merit of Claude Bernard and the medical schools that placed the experimental method at the forefront in the clinic. This striving to study not only the static of the pathological process and pathological-anatomical changes in the organ, as sedes morbi, but also the dynamics of suffering, led to the question of determining the function of the organ and the change in this function in disease, to the study of functio laesa, which had long been known as an expression of organ disease in the inflammatory process. And this was all the more tempting because pathological anatomy, as it became obvious, did not bring sufficient clarity to the question of the change in organ function, revealing only its morphological changes, not always reflecting functional disorders. Hence arose the striving to define in the clinic of internal diseases not only organic but also functional diseases, and, alongside physical diagnosis, which had grown into a systematic doctrine on the basis of the discoveries of Auenbrugger, Corvisart, and Laennec, a new functional diagnosis arose, aiming to capture the gradual transition from the normal function of the organ to the pathological, to its functional disease, along with anatomical changes or even without them, since it is conceived that the material basis of disease may lie beyond the reach of the best microscopic optics and technique. The founder of functional diagnosis can be considered Rosenbach (see Diagnosis). The modern clinic of internal diseases possesses a whole series of delicate methods for studying the functions of internal organs, such as graphic methods for studying cardiac activity, determination of blood pressure, techniques for studying the secretory and motor functions of the stomach and intestines, determination of various functions of the liver, bile ducts, functional diagnosis of kidney activity, etc. To this same epoch belongs, as a result of the discoveries of Pasteur, Metchnikoff, Koch, the brilliant flourishing of bacteriology, due to the application of the experimental method, and at the same time—the flourishing of hopes to obtain an exact solution of the question not only of sedes but also of causa morbi. This striving to find an etiological-pathogenetic approach to the understanding of many internal diseases for a time shifted the attention of physicians from the evaluation of the entire organism (macroorganism), fixing their attention on the discovery of the microorganism and the study of its morphological and biological properties. Morphological thinking as a result of the ideas underlying cellular pathology and the experimental method with the study of organ functions dominate the clinic of internal diseases from the end of the 19th century to our day. Along with inexhaustible successes and achievements, both these directions in internal medicine stopped the attention of the last generations of physicians, mainly, on the objective clinical-laboratory method of studying the patient. In various clinics and schools of internal diseases, the morphological, pathological-anatomical or more functional, pathophysiological approach to the study of the disease predominated alternately. Both these currents, essentially not excluding each other, have exerted a very serious influence on the development of the doctrine of internal diseases. Deepening the internist's understanding of pathological processes, they led to a significant accumulation of the most diverse and seemingly completely objective facts, verified by the methods of exact science, facts about the essence of various diseases, about the processes underlying the disease and its symptoms, about the causes of diseases and, finally, about rational methods of treating them and contributed greatly to the progress of internal medicine. The successes of surgery, the enormous achievements of technology in recent decades have made it possible to verify the results of refined diagnosis, and the new morphological and experimental methods seemed to promise to place the doctrine of internal medicine alongside the exact scientific disciplines. During these years, a considerable number of theories arose to explain various internal diseases and their origin, and the synthesis of facts obtained by the experimental method and verified morphologically did indeed fully confirm part of these theories. However, as facts accumulated, a number of circumstances became clear that forced internists to reassess the values obtained by both cellular pathology and the experimental method. Not to mention that as the factual material accumulated and the critical attitude of physicians toward it grew, a large number of working hypotheses and seemingly fully experimentally substantiated theories had to be abandoned and replaced by others, which also proved short-lived—theoretical systems, built on the principles of cellular pathology and even on experiment, could not explain a number of clinical facts and, especially, therapeutic methods established by thousands of indisputable observations by physicians of various countries. Theoretical medicine did not give an explanation for the undoubtedly beneficial influence of a number of therapeutic methods, such as bloodletting, distracting agents—therapeutic methods sanctified by experience and folk medicine and the old Hippocratic school. These circumstances created considerable cooling among the mass of practical physicians toward theoretical premises and contributed to the completely unexpected flourishing of quackery and charlatanism in the largest medical centers of Europe and America, precisely where the newest clinic of internal diseases made its greatest discoveries on the soil of pathological anatomy and experiment.

The etiological approach to solving the causes and essence of a number of diseases, despite the enormous achievements of bacteriology, also did not justify the hopes placed on it in the last quarter of the 19th century; the discovery of the pathogen of the disease proved to be not equivalent to the question of the essence of the pathological process, and even therapia magna sterilisans practically did not lead in the body to what could be seen and done in vitro. Meanwhile, the progressive course of experimental medicine led to new and completely unexpected, for example, for representatives of cellular pathology, results that threatened to completely undermine the well-ordered and beautiful building of Virchow's teaching on sedes morbi. The experimental method, which created bacteriology and the doctrine of immunity, led precisely to new views on the essence of disease and to a revision of the localistic doctrine itself. Of course, the cells of the body participate in immunobiological processes, but sedes morbi cannot always be indicated, it is often in many organs; new substances appear in the tissue fluids and in the blood, and the blood serum reflects the biological processes in the cells. The same experimental method led to the doctrine of the autonomic nervous system (Langley), which governs and coordinates the activity of various organs and their systems in a healthy person and, especially, in a sick person, and subordinates the functions of the organ to the directives of the central nuclei in the medulla oblongata and intermediate brain. The experimental method showed the intimate connection between the activity of an organ and the autonomic and central nervous systems and outlined the ways of studying the behavior of an organ in connection with the activity of the higher nervous system (school of Pavlov), explaining a number of pathological facts that were previously incomprehensible from the point of view of an isolated organ. Thus, the question of the relationships and closest connection between somatic and mental processes in the healthy and sick body was raised—a question well known to the Hippocratic school. The experimental method revealed the role and essence of the internal secretion organs, showed the importance of hormones for the correlation of the activity of various systems and singled out the most important hormones—adrenaline and insulin, giving them into the hands of the physician for therapeutic purposes, apparently clarifying the mutual relationship of the individual parts of the complex endocrine system and its influence on the autonomic part of the nervous system. The experimental method established the constancy of the physical and chemical properties of the blood, established the isoosmia, isotonia of the blood in relation to its main components: electrolytes, mineral salts, blood sugar, and the dependence of the composition of the blood on the tone and condition of the central nuclei of the autonomic nervous system, regulated by the blood flowing over them. The experimental method proved the presence of very fine instruments regulating the interrelationships between organs, by coordinating the work of various parts of the endocrine apparatus and the autonomic nervous system, thus creating, by both nervous and humoral paths, that consensus partium which, according to modern views, lies at the basis of the normal functions of organs and their systems. Thus, the experimental method, applied to the study of the sick person, to a large extent undermined the basic foundations and very foundation of cellular pathology, putting in place of the localistic understanding of the disease the organism in all its harmonious wholeness as a single psycho-physical unit; on the other hand, the experimental method revived, it is true, in a completely new form, the ancient humoral pathology, basing it this time not on speculative premises, but on concrete, precise, scientifically verified facts establishing the pathological functions of organs in connection with the presence in the blood of this or that pathological relationships of the 'juices' of the body. Of course, all these facts in no way diminish the real achievements of the morphological method. But, along with sedes morbi, they emphasize the importance of functio laesa of the organ and place the disease of the organ in a close causal connection with the disease of the entire organism. Instead of localized diseases, they put forward on the first place precisely those general, universal diseases, the existence of which Virchow so categorically denied. All these enormous successes of the experimental method in the clinic of internal diseases were, however, in large part accompanied by negative aspects of clinical-experimental thinking. Just as the morphological approach fixed the attention of internists on individual organs, diverting it from the assessment of the organism as a single whole, so the experimental, 'pathophysiological' approach fixed the physician's attention on the results of instrumental research and often diverted him from the bedside of the patient to extensive and complex laboratory work. Observation of the patient himself, which was placed in the first place in old medical schools, was often replaced by the desire to obtain a series of completely objective laboratory data. Under the influence of the successes of experimental research and laboratory techniques, even the greatest clinicians often gave preference to the objective method of research over the study of the patient's complaints. Such a great clinician and expert on stomach diseases as Leube said that a detailed interrogation only leads to a loss of time in the diagnosis of stomach diseases. But the disappointment in a number of seemingly impeccable laboratory methods of patient research led internists to the need to again give first place to the old, proven method of direct observation at the bedside of the patient, somewhat neglected in the years of the vigorous development of the morphological and experimental methods of studying diseases. This also explains the fact that, despite the enormous authority of the new doctrines—cellular pathology and experimental thinking—parallel with them in the 19th century and the first decades of the 20th century, the clinic of internal diseases produced a number of brilliant physicians who continued careful observations on the patients themselves by the methods of the Hippocratic school, transferred through the era of speculation and scholasticism by Sydenham and Boerhaave. The most brilliant representatives of such therapists-clinicians, founders of therapeutic schools in the 19th-20th centuries are: Broussais, Laennec, Trousseau, Charcot, Dieulafoy, Huchard—in France, Schönlein, Wunderlich, Frerichs, Traube, Kussmaul, Leyden, Senator, Naunyn, Neisser—in Germany, Skoda, Nothnagel—in Vienna, Brinton, Addison, Bright, Mackenzie and others—in England, Zakharyin, Botkin, Ostroumov and Obraztsov—in Russia. Despite the different medical worldview and different approaches to the study of the patient, it is these great clinicians who identified a number of new diseases of internal organs and created the modern doctrine of internal diseases. Thus, it is clear that throughout the 19th century, along with the desire to create well-ordered and strictly scientific medical systems on the soil of rational thinking and on the basis of exact natural sciences, the clinic of internal diseases did not abandon the methods of the Hippocratic school. And for the beginning of the 20th century, it can be considered characteristic the desire for critical application in the clinic of theories arising from the morphological and experimental methods of the past century, and the deepening of the study of the human patient by the latest functional research methods. Internal diseases as a separate discipline began to be studied in Russia only in the second half of the 19th century. Until that time, therapy was dominated mainly by the views of Brown and Broussais; active therapeutic methods were applied, distracting treatment was strongly recommended, bloodletting in all its forms. The construction of the Russian school of internists began only in the 1860s of the 19th century, when two schools arose simultaneously: the Moscow school of G. A. Zakharyin and the St. Petersburg school of S. P. Botkin (see Zakharyin, Botkin, Ostroumov). Despite the fact that Zakharyin received his education from Virchow and studied abroad precisely in those years when the morphological and experimental methods of clinical thinking were being created there, he placed in the clinic the study and observation of the patient himself at the forefront, and above all, deep individualization of each separate case, and in therapy—empiricism based on observations and personal experience. Zakharyin avoids theoretical premises for his diagnosis, and especially for justifying the indications for his therapy. A feature of Zakharyin's school is the comprehensive study of the patient and, above all, a detailed analysis of subjective complaints and living conditions. The interrogation of the patient, which due to theoretical considerations was being ignored by most internists precisely in this era, is brought by Zakharyin to the height of virtuosity and is developed as a well-ordered system and the most essential part of medical research. Zakharyin assigns a small place in the clinic to the experimental, laboratory method. The founder of the St. Petersburg school of internists, S. P. Botkin, had a particularly great influence on the development of the doctrine of internal diseases in Russia.

Striving to give a strictly scientific foundation to the phenomena observed at the patient's bedside and to explain the mechanism of the origin of disease symptoms, Botkin relies in clinical practice on the great achievements of the morphological and experimental methods, and, possessing a critical mind and exceptional intuition, builds on a strictly scientific foundation a series of brilliant theories and hypotheses, discovers new symptoms and new clinical pictures of disease. Botkin is not, however, a blind follower of a particular theoretical doctrine. Putting detailed objective examination of the patient in the first place, he nevertheless does not subordinate clinical practice entirely to the results of laboratory research. A great clinical thinker, he evaluates the results of his therapy with skepticism and great scientific criticism, is not an advocate of vigorous therapeutic measures, and demands from the physician a cautious approach to the treatment of the patient, which if possible is based not only on personal experience and empiricism, but follows from an understanding of the essence of the disease and the pathogenesis of its symptoms. A. A. Ostroumov - the third greatest Russian internist of the late 19th century. Attaching enormous importance in clinical practice to the theoretical premises of the preceding era, he studies the patient as a single whole and the disease as an expression of the struggle of the entire organism with harmful influences of the external environment. Hence the new biological approach in understanding the dynamics of the disease and the evaluation of the individuality of the patient, both in his hereditary past and in the external conditions of his life that caused the pathological process. As the successors who built Russian therapeutic clinical practice, one can name N. A. Vinogradov, V. G. Lashkevich, V. A. Manassein, Yu. T. Chudnovsky, L. V. Popov, S. V. Levashchev, N. Ya. Chistovich and V. P. Obraztsov. A number of brilliant contemporary clinicians continue the work of the founders of Russian clinical practice of internal diseases. One can see that specialization in individual medical disciplines and the division of internal diseases themselves into new specialties have led to a significant deepening of our knowledge, to the discovery of the latest subtle research methods and to the identification of a whole range of new clinical forms of diseases of internal organs. But this fine specialization and fragmentation of the clinical practice of internal diseases into parts has, of course, major negative aspects. If under the influence of Virchow's localist doctrine and the experimental method our knowledge deepened, then the evaluation of the disease as a biological reaction of the entire organism and the treatment of diseases of internal organs as a biological process in the entire organism receded to the background and often very far. The laboratory and experiments distracted the internist from the patient himself. In the 1890s, voices already appear (Rosbach, Zimsen and others) warning internists against fascination with theoretical systems of thought and against extremes in their application in clinical practice. The great attraction of younger generations of physicians to laboratory, precise and strictly scientific methods of studying diseases has reduced the practical experience of internists and led to nihilistic attitudes in the treatment of internal diseases. The disease has taken the place of the patient. The best physicians (Mackenzie) insist on the need to return the internist to direct observation of the patient, to work at the patient's bedside and in the outpatient clinic. Krehl, F. Kraus, His, Sahli, Bergmann and others raise the question of the possibility of building the practical work of the internist only on exact data from theoretical medicine. As a result of this, despite the enormous successes of technology and experiment, the clinical practice of internal diseases of our time has a definite tendency to consider diseases of individual organs only in close connection with the biological processes taking place in the entire organism. Not excluding morphological analysis and due respect to the results of pathological-anatomical research, internists nevertheless put in the first place the functional approach; clinical practice strives to create a functional pathology of internal organs. Taking into account the constitution of the patient, modern clinical practice of internal diseases pays attention, besides somatic aspects, to the psychological features of this constitution, understanding the organism as one, completely inseparable psycho-physical whole, and the disease as a reaction of this whole to harmful influences of the external environment. The disease does not represent something fixed, that can be fixed morphologically or experimentally; like every biological phenomenon, like every life, the pathological process of the organism is very dynamic and subject to constant fluctuations and changes. That is why the study of the patient is conceived only as the study of experimenti naturae. Studying individual organs and the manifestation of disease in them, the modern internist is interested in the question of sedes morbi, but focuses his attention on solving the task of functio laesa, putting this solution in the plane not only of the individual organ but also of changes in the functions of the unified organism. Thus, modern internal medicine sees in functional diagnostics only a tool for its ultimate goal - functional pathology. Hence are determined also the paths of modern therapy. The constitution of the patient predetermines the course of the pathological process; the task of the internist, having studied the constitutional features of his patient, is to notice the paths chosen by the organism to fight harmful influences and to assist this fight, strengthening for it the protective forces of the entire organism, and not only of its individual organ. Hence - the use of natural healing forces of nature - food, climate, air, light, water, electricity - dietetics, physiotherapy with balneotherapy, and finally psychotherapy as a powerful method of influencing not only mental but also somatic processes in their inseparable connection in the organism. Hence the subordinate role only of symptomatic drug therapy, where even so-called specific agents (quinine, mercury, iodine and salvarsan) are applied not in expectation of their action in vitro, but taking into account the protective forces of the organism itself. Hence the wide application of irritating non-specific therapy, return to so-called counter-irritants, restoration of bloodletting. Without abandoning the position of attentive observation of the patient, the internist no longer treats therapy so cautiously only because he does not know exactly the mechanism of action of the therapeutic method. The Hippocratic principle - natura sanat, medicus curat - again begins to dominate in internal clinical practice. But the influence of the external environment and the entire setting of the organism in it, the conditions of life, labor and profession, the economic and social prerequisites of those exogenous harmful factors, the result of which is the disease, lead the internist to preventive therapy, which at all times has been the main and most important task of the physician. The creation of a system for this scientifically-based prevention of internal diseases and constitutes the immediate goal of the clinical practice of our time. Thus, enriched by the great conquests of theoretical medicine, as a result of positive medical thinking, the practical work of the modern internist leads him again to fulfilling the greatest precepts of the Hippocratic school: to the comprehensive study and observation of the patient's organism as a single whole in connection with its environment, to the understanding of internal disease as a general reaction of the organism to harmful irritation, and to the view of therapy as prevention of disease and strengthening of the natural protective forces of the organism in its struggle. But this Hippocratic thinking is now based not on the great intuition of the creator of the Cossack school, but on the results of scientific concepts of disease and its essence.

R. Luria.