"Efficiency in science is first of all fundamentality": a quantitative history through the prism of the personal archive of Academician I.D. Kovalchenko

Borodkin Leonid Doctor of History Corresponding Member of the Russian Academy of Sciences, Professor, Head of the Department for Historical Information Science at Lomonosov Moscow State University (MSU) 119991, Russia, Moskva oblast', g. Moscow, ul. Lomonosovskii Prospekt, 27-4 borodkin-izh@mail.ru Other publications by this author

The scientific work of Ivan Dmitrievich Kovalchenko (1923-1995), an academician of the Russian Academy of Sciences, an outstanding historian, a world-renowned scientist, is reflected in his numerous articles and monographs. However, a lot of interesting things about him can be found from his personal archive. It is this material that forms the basis of this publication.

Ivan Dmitrievich was born on November 26, 1923. In the days when these lines are being written, he would have turned 100 years old.  This is a good reason to once again "take a look" at the development of the interdisciplinary field of historical science, which arose in the early 1960s and was called "Quantitative methods in historical research." The pioneer of this direction, its leader in our country from the very beginning was I.D. Kovalchenko. We emphasize that Ivan Dmitrievich made a major contribution to a number of areas of historical science, including, first of all, the theory and methodology of history, the source study of national history, agrarian (and, more broadly, economic) history. During the three decades that have passed since his death in 1995, many works have been published assessing the role and contribution of I.D. Kovalchenko in the development of the direction "Quantitative methods in historical research" (or quantitative history, as this direction is often called). A significant part of these publications is contained in six volumes of materials of Scientific Readings in memory of Academician I.D. Kovalchenko, published in 1997-2020. In this article, we rely mainly on the published materials of the academician's personal archive.

For several years after the death of I.D. Kovalchenko, a group of employees of the Department of Source Studies of the Moscow State University Faculty of History, with the participation of a number of faculty colleagues (including employees of the Laboratory of Historical Informatics), employees of archives and other organizations, carried out extensive work on preparing for publication a collection of materials from the academician's personal archive. The main work on the compilation and preparation of the text and notes was carried out by T.A. Kruglova, A.E. Shiklo and T.V. Kovalchenko. This volume (520 pages) was published by ROSSPAN Publishing house in 2004 ^[1].

This article is devoted to important aspects of the scientific and organizational activities of Academician I.D. Kovalchenko in the field of application of mathematical methods and computers in historical research. This is a look through the prism of the academician's personal archive.

In his answers to the questionnaire of the Institute of Sociological Research of the USSR Academy of Sciences (1987), Kovalchenko noted that "the tendency to transfer to science the concept of efficiency, taken from technology and production and understood in applied terms, is erroneous. Efficiency in science is primarily fundamental" ^{[1, p.455]}, which he often associated with the validity of the research methods used, emphasizing that they "are the most dynamic component of science that moves it forward" ^{[2, p.4]}. Quantitative methods occupied a priority place in the methodological tools the academician.

Colleagues who worked with academician I.D. Kovalchenko, students and followers note his high qualities as a person, scientist, and university professor. As noted by T.A. Kruglova, who worked a lot with the materials of the academician's personal archive, these materials complement and enrich our understanding of these qualities of Ivan Dmitrievich ^{[3, p. 290, 286]}.

Ivan Dmitrievich was a principled man, and at the same time he could be diplomatic in solving complex issues without sacrificing principles. Such difficult questions often arose in his work, given that for almost 30 years he was the head of the Department of Source Studies at the Faculty of History of Moscow State University, for almost 20 years he was the editor-in-chief of the journal "History of the USSR", and in 1989-1995 he was the academician-secretary of the Department of History of the USSR Academy of Sciences (RAS). Of course, this is not a complete list of his scientific and organizational positions. Surprisingly, Ivan Dmitrievich successfully coped with all these responsibilities – thanks to a sense of responsibility, the ability to manage his time, and internal discipline.

I can't help but note the genuine democracy and modesty inherent in him. In a reply letter to the correspondent of the Bryanskaya Gazeta on November 15, 1993, he writes: "There is nothing much to write about myself. Before the war, he studied at school in Moscow. Participant of the Great Patriotic War. He ended the war in Hungary, Austria and Czechoslovakia. He served in the airborne forces. He was the commander of the gun. After the war, he studied at the History Department of Moscow State University. I also work there after graduating from graduate school in 1955. I am the head of the department (since 1966). In recent years I have been working at the Academy of Sciences. I study the agricultural history of our country in the XIX – early XX centuries and the use of mathematical methods and computers in historical research" ^{[1, p. 282]}.

I remember how on May 9, in the 70s - 80s, faculty members of the war, veterans wore front–line awards, and on one of these days I asked Ivan Dmitrievich about his Order of the Red Banner - one of the highest Soviet awards, which soldiers and sergeants were very rarely awarded (Ivan Dmitrievich ended the war in 1945 G. with the rank of Guard senior sergeant, commander of a 76 mm cannon battery).  He answered briefly ("for the battles in Hungary") – like most front-line soldiers, he rarely touched on the topic of his participation in the war. And only in 2015, an information request to the database "Feat of the people in the Great Patriotic War of 1941-1945" allowed us to identify the award list, which testified that I.D. Kovalchenko was presented to the title for crossing the Raba River in Hungary in March 1945 and the battle on the bridgehead Hero of the Soviet Union, however, this representation of the regiment commander and division commander was not approved "at the top", as a result, Ivan Dmitrievich was awarded the Order of the Red Banner. In the spring of 1945, he was less than 22 years old.    

Becoming

Let's return to the question of quantitative methods. In his 1961 memoirs, Ivan Dmitrievich writes that if he had had to go to university not after the war, he probably would have gone to the physics department. But his choice to become a historian was largely determined by the war he went through from 1941 to 1945. The war "pushed many people's thoughts towards social phenomena, aroused a natural interest in the causes that determined events in people's lives" ^{[1, p.407]}.

Perhaps the initial attitude to the study of exact sciences predetermined his aspiration to use quantitative methods and computers in historical research. A certain role in the formation of this aspiration could also be played by the factor of his special education in 1940-41, when he studied for a year at the artillery special school in Moscow, and then at the Ryazan Artillery School (for four months). 

In this regard, the observation of T.A. Kruglova, who worked a lot with the materials of I.D. Kovalchenko's personal archive, is of interest. In his thesis, I.D. Kovalchenko turned to the analysis of A.N. Radishchev's work "Description of my possession", which contains a lot of quantitative data. Describing the article by the famous historian P.G. Lyubomirov about this work by A.N. Radishchev, the graduate student writes in his notes: "From here it is clear how important the figures in the article are, which Lyubomirov discounted... Lyubomirov says this, but he could not draw any conclusion, he deprived himself of weapons by throwing out the numbers” ^{[3, p.281]}.

Let us briefly consider the early period of I.D. Kovalchenko's research work related to the active use of mathematical and statistical methods. The first stage falls on the 1950s – 1960s. These were the years of preparation and defense of candidate's (1955) and doctoral (1966) dissertations, marked by the publication of two monographs that significantly advanced the study of the Russian serfdom of the first half of the XIX century. In the first monograph ^[4], the scientist studied the materials of the peasant and landowner farms of two provinces based on household censuses of four estates of the first half of the XIX century, and in the second ^[5] data were analyzed on hundreds of estates of provinces of pre-reform European Russia to study the production aspects of the peasant economy and the nature of the processes of property and social stratification of the peasantry.

An important feature of Ivan Dmitrievich's research is attention to the correctness of the use of mathematical and statistical methods. While working on his doctoral thesis, he established contacts with scientists from the Department of Probability Theory of the Faculty of Mechanics and Mathematics of Moscow State University. In this context, the following fragment of the review of the abstract of I.D. Kovalchenko's dissertation, signed by the famous mathematician-probabilist, associate professor of this department V.N. Tutubalin, is of interest: "The considerations that I.D. Kovalchenko cites in favor of the applicability of the statistical techniques he uses were discussed in detail at a seminar meeting of the statistical laboratory at the Department of Probability Theory. According to the general opinion of the seminar participants, the level at which I.D. Kovalchenko justifies the applicability of the methods used in the work is quite consistent with what is generally accepted in applied statistics" ^{[3, p. 281]}.

         Already at this early stage of the formation of a new direction, he shows interest in its development abroad. In a letter to Arkady Kagan (Arcadius Kahan, professor of economic history at the University of Chicago) in the fall of 1966, I.D. Kovalchenko expresses his gratitude for the offer to send the literature he is interested in and clarifies: "I would be interested, first of all, in works in which mathematical methods and electronic machines were used in the analysis of historical plots" ^{[1, p. 318]}.

Despite the discussions that accompanied the first reports and publications of Kovalchenko and his colleagues, carried out using mathematical and statistical methods, a number of major historians, specialists in the history of pre-revolutionary history of Russia noted the effectiveness of the use of new methods in his works. So, in 1966, one of the official opponents of I.D. Kovalchenko's doctoral dissertation, Professor V.K. Yatsunsky, noted in his review: “The author of the dissertation belongs to one of the very few historians who know the methods of mathematical statistics. He applies these methods extensively in his dissertation. I cannot refrain from expressing praise to the dissertator in this case” ^{[1, p.318]}. This comment by Yatsunsky is all the more valuable because both scientists differed in their assessments of such important aspects of the history of pre-reform Russia as the degree of development of capitalist relations in the countryside, the nature of the stratification of peasants, etc. We also note their differences in assessing the degree of reliability of the governor's reports. This can also be judged by Ivan Dmitrievich's answers to the comments made in V.K. Yatsunsky's review ^{[1, pp. 50-52]}.

Another manifestation of a positive assessment of his work in this area is contained in a letter from academician N.M. Druzhinin to the editor-in-chief of the journal "Questions of History", corresponding member. To V.G. Trukhanovsky of the Academy of Sciences of the USSR on the question of the expediency of introducing I.D. Kovalchenko to the editorial board of this journal. N.M. Druzhinin's letter notes:

 "ID. Kovalchenko is a young talented scientist who combines extensive knowledge, a broad outlook, correct methodological points of view, the ability to pose and correctly resolve major issues of historical science. In his doctoral dissertation, attention is drawn not only to the richness of the sources involved and the subtlety of argumentation, but also to the application of the latest techniques of electronic computing to the development of statistical materials. Hence the credibility and value of the scientific conclusions he obtained. I am sure that due to his high qualities and great efficiency, I.D. Kovalchenko will be of great benefit to the editorial board of the journal" ^{[1, p.336]}.

At this stage, in the first half of the 1960s. Kovalchenko goes beyond individual work in a new field. His personal archive contains a memorandum sent by him in January 1963 to the Rector's Office of Moscow State University and to the Dean's Office of the Faculty of History. In the preamble of this document, the associate professor  Kovalchenko writes: "The radical improvement of the methodology and technique of scientific research, which is currently taking place on the basis of the widespread use of mathematical methods and modern computer technology, sooner or later will cover all areas of science. Currently, there is a need to apply new methods in the field of historical science" ^{[3, p.291]}. In support of this thesis, the author points out that this will significantly expand the range of the studied factual material and carry out such processing, which is practically impossible at present. It should be noted that, having by this time experience in processing statistical sources on a computer, he also sees the relevance of working with other sources: "Further development of computer technology and the appearance of machines adapted to text processing will radically change the work of historians not only in the field of socio-economic, but also other issues, as well as in in the field of bibliography, chronology, etc." ^{[3, p.291]}.

Further, the memorandum states that Moscow University has everything necessary to expand the work on the use of electronic machines in historical science. In this regard, the author notes that the Faculty of History has a group of teachers interested in the development of this area, who want to be able to contact the staff of the Computing Center of Moscow State University to prepare source materials for processing on a machine and carry out such processing. The compiled list included 10 teachers of the Faculty of History, including future professors who became authors of works using quantitative methods (V.M. Selunskaya, V.Z. Drobizhev, V.I. Kuzishchin, L.M. Bragina, Yu.L. Shchapova) ^{[3, p.291]}. Of course, not everyone was able to master the difficult courses, but Ivan Dmitrievich held on the longest. "The stage of such experimentation is necessary," he noted in the memo under consideration and suggested "organizing classes with this circle of interested people, which will be conducted by specialists of the mehmat. The purpose of the classes is to introduce historians to the basics of higher mathematics, probability theory, mathematical statistics, principles of operation and capabilities of electronic technology, the basics of programming" ^{[3, p.291]}. Interestingly, 10 years later, the outstanding French historian Le Roy Ladury will pronounce his more radical thesis: "The historian of tomorrow will be a programmer, otherwise he will not be."

The memo concludes with a proposal to create a laboratory at the faculty for the use of electronic machines in historical research (a description of the activities and structure of the laboratory is provided).

Development

It must be said that the plan proposed by I.D. Kovalchenko for the creation of a laboratory was gradually implemented, and in the 1970s a group on the application of mathematical methods and computers was created in the structure of the Department of Source Studies (which he headed since 1966), and in 1991 this group was transformed into the laboratory of historical Informatics (since 1996 – named after Academician I.D. Kovalchenko). In 2001 it received the status of the General Faculty Laboratory of Historical Informatics - until its transformation into the Department of Historical Informatics of the Faculty of History of Moscow State University in 2004 (in accordance with the decisions of the Academic Council of the Faculty of History, the Academic Council of Moscow State University and the order of the Rector of Moscow State University).

     The first personal computers in the laboratory of historical informatics appeared in 1988 (three Soviet PCs "Neuron"), their acquisition by the faculty required the participation of Ivan Dmitrievich. The problem with historians' access to high-performance computers was also at a higher level. The academician's personal archive contains his letter to the famous American historian and economist Paul Gregory (April 1990) about a joint project to study the dynamics of Russia's economic development in the late XIX - early XX centuries, create a database, and prepare relevant publications. At the end of the letter, Kovalchenko writes that in order to implement the tasks of the project, "it is highly desirable for the American side to provide the Soviet side with at least several computers for temporary use" ^{[1, pp.279-281]}. In the same letter, he informs P. Gregory about the creation of a Consortium for databases and the development of historical research methods within the framework of a joint project at the Department of History of the USSR Academy of Sciences. In particular, we are talking about the formation within two years of data sets characterizing the dynamics of agricultural and industrial production, as well as transport in pre-revolutionary Russia. ^{[1, p.280]}.

The second stage of the early period of I.D.Kovalchenko's statistical research falls at the end of the 1960s - mid–1970s and is associated with his joint work with L.V. Milov on the study of the formation of a single agricultural market in Russia in the XVIII - XIX centuries, which ended with the publication of a fundamental monograph ^[6].

The authors note that they relied on a huge amount of computational work and analyzed about 150 thousand coefficients, constructing on this basis a number of structural correlation models of the market characteristic of various stages of its development ^{[6, p.2]}. In this study, the methodology is based on calculations of correlation of dynamic series of regional market indicators. One of the questions that arise during such calculations concerns the correctness in the methodology of accounting for trends contained in the series of dynamics. I.D.Kovalchenko, striving for maximum correctness of the statistical calculations used by him, entered into correspondence in 1969 with N.S. Chetverikov, a famous Soviet statistician of the Chuprov school, a specialist in the field of socio-economic and mathematical statistics, who developed, in particular, mathematical methods for analyzing dynamic series, applications of correlation and probability theory. Chetverikov, who published articles on statistical processing of agricultural indicators dynamics back in the 1920s and continued these studies in the 1960s, responded to a letter from I.D. Kovalchenko and sent detailed comments on the method of correlation of dynamic series of random price fluctuations ^{[1, pp.369-376]}. Judging by the materials of the monograph by I.D. Kovalchenko and L.V. Milov, they were taken into account by the authors.

             In 1968, Kovalchenko initiated the establishment of a Commission on the application of Mathematical Methods and Computers in Historical Research at the Department of History of the USSR Academy of Sciences. The institutionalization of a new direction has begun. In 1979, the Commission and the Department of Source Studies of the History of the USSR of the Faculty of History of Moscow State University organized a permanent scientific All—Union seminar "Quantitative methods in historical Research" (seminar leaders - corresponding member. Academy of Sciences of the USSR I. D. Kovalchenko and D. I.N. L. I. Borodkin). The hundredth meeting of the seminar took place in 1992; in fact, it was an international seminar, for 15 years more than 50 foreign scientists made presentations at it ^{[7, pp.232-234]}. An important area of work to involve young scientists, postgraduates and students in a new direction has become schools-seminars on new methods of historical research, supported by Moscow University (Suzdal, 1984; Rostov Veliky, 1986; Moscow region, 1988). These schools, whose scientific director was invariably I.D. Kovalchenko, gathered about 100 young participants. The commission, headed by I.D. Kovalchenko for a quarter of a century, became the coordinator of work in this area in the USSR, initiated the organization of new laboratories of this profile, conferences, and the publication of a series of collections of works by Soviet quantifier historians (more on this in ^[8]).

In his interview with the Newsletter of the Commission on the Application of Mathematical Methods and Computers in Historical Research at the Department of History of the Russian Academy of Sciences (1992), Ivan Dmitrievich noted that a long way had been traveled in a quarter of a century: "from combat reconnaissance, which took place in the 60s, through the identification of problems, the solution of which requires the use of quantitative methods and Computers, and the approbation of various methods in the 70s to the analysis of many complex phenomena and processes of historical development based on the application of new methods in the 80s" ^{[1, p.464]}. At the same time, he does not contrast cliometrist historians with other historians in this interview, emphasizing that the use of mathematical methods and computers alone does not provide "an automatic increase in the essential, meaningful, qualitative level of historical research. This also requires high professionalism in its theoretical and methodological, source-historiographical and content-historical aspects. Unfortunately, this is often forgotten when turning to new methods" ^{[1, p.464]}. This provision continues to be no less relevant today. It fully relates to the direction of quantitative history, which Ivan Dmitrievich became interested in in the mid-1970s and which he repeatedly turned to in the next 20 years – we are talking about modeling historical processes and phenomena.

On modeling historical processes

         I.D. Kovalchenko's first works devoted to the possibilities of mathematical (computer) modeling of historical processes appeared already in the 1970s in the context of the attention he paid to methodological problems of applying quantitative methods in historical research. The main work of those years was an article published in 1978 in "Questions of History" ^[9]. Many pages in the materials of the scientist's personal archive are devoted to modeling issues in history.

         His correspondence with the editorial board of the journal "Questions of Philosophy" (VF), which published in 1986 a positive review of the book by A.S. Huseynova, Yu.N. Pavlovsky, V.A. Ustinov on the experience of simulation of the historical process, published in 1984, is characterized by acute controversy ^[10]. The authors of the book presented the work of a team of mathematicians and historians who undertook the creation of a mathematical model of the Peloponnesian Wars (431-404 BC) in the 1970s. I.D. Kovalchenko in June 1986 wrote a critical response to this review (a kind of "review for review"), offering it to the same journal. In his response letter, he notes that mathematical simulation is "the most important and powerful scientific and cognitive method" that can be successfully applied in the study of historical processes and phenomena. However, he evaluates the "experiment done" as a failure, noting the inconsistency of the position of the reviewers of the book, who give a high overall assessment of it in the presence of a number of serious comments ("the issues of consistency and adequacy of the developed model, its validity, etc., have not been sufficiently considered").

Kovalchenko further notes that the authors of the review, like the authors of the book, do not take into account the specifics of the simulation of historical processes. Although the historian should strive for an invariant reconstruction of the past, the latter can be both unconditionally unambiguous and probabilistically unambiguous.   However, a situation often arises when the available data is insufficient, and here Ivan Dmitrievich makes a breakthrough proposal: reconstruction in this case can only be variant and hypothetical. And one of the tools of such reconstruction can be simulation modeling, which allows to identify "objectively possible trends   and the directions of development and the limits of variation of certain characteristics of the object" and the development options determined by them.  But the authors of the Peloponnesian Wars model form the structure of the system they are considering on the basis of its concrete historical analysis, and postulate it a priori, based on the authors' views on the nature of the existing relationships: "The economic dynamics of policies recreated by the model should meet our views on the interconnection of all... factors" - the scientist quotes the authors of the book and concludes with the conclusion that the theoretical and methodological problems of simulation modeling are insufficiently developed ^{[1, p.147]}.

Further correspondence between I.D. Kovalchenko and the editorial board of "VF" is of interest. In response to his letter, the editor of the journal's department wrote on November 16, 1986, that he considers as methodologically correct the authors' view that "the model is just a tool for meaningful analysis and as such should correspond to the Marxist-Leninist point of view on the course of historical processes" ^{[1, p.275]}. The editorial board's response disagrees with Kovalchenko's statement that any simulation should always be variantwise, "because this requirement contradicts the very definition of a simulation model as an algorithm that uniquely connects input parameters with output parameters. As noted in the review, only an imitation-game model can provide variation." (I note in parentheses that it is difficult to agree with this - in the course of simulation modeling, the practice of varying the values of model parameters is common, which makes it possible to realize its multivariance - LB). Disagreeing with the arguments presented in Kovalchenko's letter, the editorial board concludes the letter by stating the inexpediency of further discussion on the topic of modeling in history.

On November 25, 1986, Kovalchenko wrote a reply to the editorial board of VF, noting that, "of course, any author is pleased that his material is accepted and not rejected." In this reply, Ivan Dmitrievich is very emotional: "And besides, he was rejected with a categorical, downright "devastating" rejection of all the considerations expressed" ^{[1, p.276]}. He does not agree "with the classification of supporters of the statistical approach only" to historical phenomena and in this regard exclaims: "Let it be known to you that I am a supporter of the use of all possible methods in historical research, including all mathematical methods (This is recorded in many of my works). But I am a resolute opponent of idealization and absolutization, and incorrect application   any particular of these methods. Your answer is the same   on   My letter is permeated through and through with the desire to whitewash just one of these methods.   Apparently, the consequence of this is the bias and partiality, contradictions and errors that your answer is filled with" ^{[1, p.278]}.

Further, Kovalchenko draws the attention of the editorial board of "VF" to the insufficient attention to the methodological aspects of historical research. As a result, he published the material of both letters to the "VF" in his works.

About alternatives

In 1989, Kovalchenko received an invitation to participate in the 1990 Nobel Symposium, held every two years and dedicated that year to the topic "Concepts of national history" ^{[1, p. 180]}. In September 1990, at this symposium, he made a presentation on "Problems of Russia and the West in pre-revolutionary and Soviet historiography."

The scientist's personal archive contains a number of materials about this symposium, including his final speech made following the discussion of his report ^{[1, p.176]}.

In this conclusion, Kovalchenko also responds to an "interesting and important problem" raised by Prof. Max Engman (Finland) - about alternative Stalinist models of building socialism.  Kovalchenko notes that this issue is also being discussed by Soviet scientists, who are considering four alternative options - the Stalinist, Trotskyist, Bukharin and the model of the first five-year plan. He reduces them to two: centralizing, forced and violent (Stalin and Trotsky) and natural history development based on the NEP (Bukharin, the first five-year plan). Kovalchenko explains the victory of the first of these alternatives by the fact that the supporters of the second failed to mobilize the relevant social forces. He agrees with American Professor S. Cohen, who published a book about Bukharin in 1980, which expresses his opinion about Bukharin as a brilliant theorist and a bad politician. "The opportunity for the natural-historical path of the genesis of socialism was missed," is how the scientist sums up the discussion of alternatives to the development of the NEP ^{[1, p. 176]}.

The topic of alternatives to historical development entered the research agenda of I.D. Kovalchenko in the mid-1980s. His program article on the possible and actual and the problems of alternatives in historical development was published in 1986 in the journal "History of the USSR" ^[11] and initiated a discussion of this topical issue. In the personal archive, the topic of historical alternatives is reflected in excerpts from the text of the manuscript of the monograph "Historical Destinies of Russia in the twentieth century", which was being prepared for publication in the last years of the scientist's life. Let us turn to the relevant fragments of the manuscript, dated in the spring of 1991.

Continuing the topic raised by Kovalchenko at the Nobel Symposium, the focus here is on the important question of to what extent the NEP model was a real alternative to the path of forced transition to socialism "based on the monopoly of the public sector in all spheres of the economy and centralist-planned leadership in all areas of public life ^{[1, p.253]}. In this regard, the scientist recalls that an alternative is such a historical situation, "which allows for significantly different outcomes of events and methods of solving important social problems. In historical reality, the alternative situation is an organic combination of objective and subjective factors." However, certain social forces are still needed that see these opportunities and are fighting for the implementation of certain of them. An important role is played here by the author's significant remark that "it is necessary to take into account the specified features of alternative historical situations in order not to look for these situations where there was no unity of their two sides, and even more so not to construct speculative alternatives" ^{[1, p.254]}. Kovalchenko admits here that "development based on the NEP model was a real alternative to solving both the general civilizational tasks facing the country and the basis of the process of the genesis of socialism" ^{[1, p.255]}.

* * *

     In the early 1990s, Ivan Dmitrievich formed the perspective problems of scientific research of the Department of Source Studies of the Faculty of History of Moscow State University.  The plan he created was called "Russia in transition from a traditionally patriarchal to an industrial society (XIX-XX centuries)." As a result of the discussion, four problems were identified:

1) Socio-economic development of Russia in the XIX – XX centuries. Sources and methods of research;

2) Socio-political and moral-psychological appearance of Russian society in the XIX – XX centuries.;

3) The masses, power and personality in Russian history. Sources and methods of study

4) Sources and methods of studying the cultural and intellectual development of Russian society.

As you can see, the issue covers the main aspects of Russian history of the last two centuries. It is still relevant today, 30 years later.  However, it was significant for me that Ivan Dmitrievich added a fifth problem: in his hand (in a characteristic handwriting, with a tilt to the left), it was added: "Problem five. Historical Informatics – computer methods of source studies" (see below):

With his inherent sense of the new in the development of science, Ivan Dmitrievich already in the early 1990s felt the approach of the era of information technology, the explosive development of electronic communications, new prospects for the use of computer methods in scientific research, including historical research. Nowadays, these changes can be described as a process of digital transformation of society, which has affected both the field of science and education.  In historical science, this process is most succinctly reflected in the materials of the journal "Historical Informatics", among the headings of which there is also "Quantitative History" – a direction pioneered by Ivan Dmitrievich Kovalchenko. The scientific school he created was able to perceive the new realities of the "digital turn" that affected historical science at the beginning of the XXI century ^[12] and develop new topical issues, adhering to the principles of interdisciplinary historical research laid down by academician I.D. Kovalchenko. They are based on the same principle: "Efficiency in science is primarily fundamental."

         I would like to conclude with a well-known thesis that has been promoted over the last 2-3 decades - about the departure of the "fashion" for quantification in history, the decline in interest in quantitative/statistical methods. Today, they no longer dare to voice this thesis, and interest in data Science has sharply increased, the traditional core of which is statistical methods. The Data Science training course is currently one of the most in-demand in educational programs of a socio-humanitarian profile. This course was introduced three years ago and for all undergraduates of the Faculty of History of Moscow State University. The case of academician I.D. Kovalchenko lives and develops.

         Referring to the materials of Ivan Dmitrievich's personal archive allows you to get to know the principles of his scientific work, the academic style of his communication with colleagues, and "look into" the laboratory of his scientific search.