70 Years of Logic in China, 1949–2019

This article outlines the history of logic in China from 1949 to 2019. Firstly, it presents a rough picture of Chinese logic before 1949 using broad brushstrokes. Secondly, it divides the whole process of development into two stages. In the first 30 years from 1949 to 1979, Chinese logic made some achievements, but also went along some detours, and its overall situation was unsatisfactory. In the latter 40 years from 1979 to 2019, due to Deng Xiaoping’s reform and opening up, many Chinese logicians went abroad for academic visits or to study degrees in foreign universities or research institutes, gradually became familiar with and even integrated into the international mainstream of logic teaching and research, and ushered in the great flourishing of logic in China we see today. Finally, it draws four lessons from this process of development, as follows. 1) Let politics and academia live in peace, by respecting and adhering to the idea of academic freedom. 2) Academic advances cannot be achieved in isolation from the world, so we should fully embrace the international academic community, while insisting on our own independent thinking. 3) We should always adhere to the policy of “letting a hundred flowers blossom and a hundred schools of thought contend”, so that different academic viewpoints and tendencies can be improved and developed in their mutual collision. 4) We should culti-vate academic self-confidence, gradually make the change from pure follow-up learning to original work in some fields of logic.

almost 30 different works in Western traditional logic were introduced to China by means of translation, including popular textbooks used at foreign universities, such as, for example, the textbook An Introductory Logic composed by the professor and head of the research institute at Cornell University in the United States. ( Ju 2013, 2) At the same time, these foreign-educated scholars also started composing their own textbooks for their courses on logic given at Chinese senior secondary schools, normal schools, and universities. Among these textbooks the most important were In 1920, in the framework of his one-year visit to China, Bertrand Russell delivered a series of lectures on mathematical logic at Peking University. Although originally four lectures were planned, the series was soon interrupted due to Russell falling ill. Later, in 1921, the notes from his lectures were collected and published in the form of a monograph by the New Knowledge Publishing House of Peking University. One year later, a Chinese translation of Russell's book Introduction to Mathematical Philosophy was also published. In that way, mathematical logic started to become known to Chinese scholars. A few years later, in 1927, Wang Dianji's 汪奠基 Treatise on Logic and Mathematical Logic (Luoji yu shuxue luoji lun 逻辑与数学逻辑论) was published, in which the author discussed the elementary principles of traditional formal logic and mathematical logic. In fact, Wang's book was an unabridged Chinese translation of his thesis from the University of Paris, but also the first textbook of mathematical logic written by a Chinese scholar. Other works containing an account of mathematical logic included Shen Youqian's Modern Logic (Xiandai luoji 现代逻辑) from 1933; Wang Dianji's Modern Logic (Xiandai luoji 现代逻辑) from 1937; Jin Yuelin's Logic, and Mou Zongsan's 牟宗三 Logical Paradigms (Luoji dianfan 逻辑典范) from 1940. Among these, only Jin Yuelin's Logic has any great success, having been used widely and thus garnered greatest influence. Originally, 1 The latter is a reprint of the 1933 edition.
2 This work was originally composed for his lectures at Beida in 1917, which is quite apparent when one looks at its language and content.
the book was the script used for Jin's lectures on logic given at Tsinghua University. It is divided in four main parts: the first part speaks about the theory of inference in traditional logic; in the second part, Jin advances a critical account of the existential problems of traditional logic, discussing in particular the existential import of subjects in categorical propositions; the third part introduces the logical system of Whitehead's and Russell's monumental work Principia Mathematica (1910)(1911)(1912)(1913), including propositional calculus, predicate calculus, calculus of classes, and relational calculus; the fourth and last part discusses meta-logic of logical systems and conceptions of logic, involving concepts like the completeness, consistency, and independence of logical axioms, and numerous other elementary logical concepts such as "necessity", "contradiction", "implication", the characteristics and status of the so-called "three laws of reasoning" (i.e. the law of identity, the law of contradiction, and the law of excluded middle), and so on. It was through Jin Yuelin's Logic and his teaching that China's earliest generation of talented scholars in modern logic was fostered, in which there was no lack of internationally respected experts like Hao Wang 王浩 and also a great number of outstanding specialists such as Shen Youding 沈有鼎, Wang Xianjun 王宪均, Hu Shihua 胡世华, Zhou Liquan 周礼全, and Yin Haiguang 殷海光, among others. Hence, one can rightly claim that Jin Yuelin was the founder of modern logic in China.
In the field of the history of ancient Chinese logic, the most influential treatise was Hu Shih's 胡适 doctoral dissertation from Columbia University entitled The Development of the Logical Method in Ancient China (English, 1922;Chinese translation, 1983). Hu's treatise was not only China's first periodized historical monograph on ancient Chinese logic, but also the first book introducing ancient Chinese logical thought in English language. Its rich, and rather original, content was of considerable reference value and enlightening impact on the later more advanced research in ancient Chinese logic. (Zhou 2004, 423) Apart from Hu' treatise there was also Zhang Shizhao's Essentials of Logic, which was both a textbook in logic as well as a study in Chinese ancient logic, in which the author strived to realize his noble aspiration to "advance a unique perspective by blending together the Chinese and the Western" (ibid.).

The Influence of Soviet Textbooks
In the ten and more years after 1949, due to then existing political circumstances the People's Republic of China (PRC) regarded the Soviet Union as its "big to Aristotelian logic, that is to categorical propositions and their inferences. Apart from such instances, there also exist textbooks which are richer with regard to the propositional logic of the Stoics, and thus compound propositions and their inferences. For the most part, however, these textbooks all contain the inductive logic of Bacon and Mill. The second common feature is that they all endeavour to found their interpretations of logical principles on the basis of Marxist philosophy, and thus to expound on concepts, judgments, inferences, truth and fundamental laws of logic in accordance with materialist dialectics. These logical textbooks also contain quite a lot of ontology and epistemology-related contents, while some textbooks even include chapters that straightforwardly discuss the relationship between formal logic and materialist dialectics.
Soviet textbooks of this kind shaped the basic pattern of Chinese textbooks on logic issued in the following two or three decades. By and large, the structure of these textbooks unfolds in the following sequence: the object and meaning of logic, concepts, categorical judgments, compound judgments, direct inference and syllogisms, inference of compound judgments, traditional logic of induction, proof and refutation, and the fundamental laws of logical reasoning. Only a few textbooks placed topics like the law of identity, law of contradiction, law of excluded middle and law of sufficient reasons in the second chapter, while some of them discussed these in the final chapter. In their investigation of logical principles and problems, these textbooks strived to implement the position, viewpoints, and methodology of Marxist philosophy.
Let us mention in passing that as late as in 1981 the Shanghai People's Publishing House still published a translation of a new Soviet textbook on logic, Formal Logic (Formalnaya logika) edited by I. Y. Chupakhin and I. N. Brodsky. This book, which was originally published in 1977, was an approved textbook used at departments of philosophy at Russian universities and already greatly differed from the former Soviet textbooks on logic, in the sense that it principally absorbed the content of modern mathematical logic. Its content was structured as follows: "Introduction"; part one, entitled "General Logic: Elementary Logical Forms and Methods of Thinking", which consists of five chapters: "Concepts, Judgments, with the Main Focus on Categorical Judgments, while also Touching upon Compound Judgments and Modal Judgments"; "The Fundamental Laws of Formal Logic, i.e. the Laws of Identity, Contradiction, Excluded Middle and Sufficient Reason"; "Inference, Speaking Mainly about Categorical Inference and its Syllogisms, Inference of Compound Judgments and Inductive Reasoning, etc."; "Logical Method of Scientific Thought, Mainly Discussing Categories, Definitions, Proof and Refutation, Method of Axiomatization, the Five Methods of Searching Causation, Hypothesis and Method of Probability, etc.". Part two was entitled "Symbolic Logic", and encompassed the following six chapters: "Truth Tables and Normal Formulae of Propositional Logic"; "Natural Deduction of Propositional Logic"; "Formalised Syllogisms"; "Natural Deduction of Predicate Logic", and "Modal Logic". Quite evidently, this represents a sample structure for an attempt to conjoin the contents of traditional formal logic and modern mathematical logic within one textbook. Although such attempts have the disadvantage of excessively mixed and disorderly contents, lacking in internal connectedness, in the final analysis they made an important first step in the direction of integrating traditional logic and modern mathematical logic.

The Great Debates on Questions of Logic under the Leadership of Mao Zedong
In the first half of the 20th century, two major debates on questions about logic took place within the Chinese academic world, behind both of which there lurked the shadow of Soviet ideology.
Around the 1930s, with its centre in the Soviet Union, in China arose a tide of rejecting formal logic by means of dialectics. In the year 1930, a widescale criticism of Deborin's school of thought broke out in Soviet philosophical circles, which itself also incorporated an overall rejection of formal logic and so on as being equal to metaphysics (in contrast to dialectics). This served as a background for the Chinese criticism and rejection of formal logic in the 1930s. In 1940, Stalin rehabilitated formal logic, and the criticism of formal logic in Soviet philosophical circles was temporarily announced as concluded, so that by 1947 the teaching of formal logic was reinstated in the Soviet Union. In 1950, after Stalin issued the document "Marxism and Problems of Linguistics", which affirmed the functions of formal logic, its position in the Soviet Union changed radically. These later developments served as the background of the development of Chinese logic in the 1950s. ( Ju 2013, 8) Back in the 1930s, a few leftist intellectuals, like Xu Kaixing 许凯兴, Guo Zhanbo 郭湛波, Ye Qing 叶青, Ai Siqi 艾思奇, Pan Zinian 潘梓年, Li Da 李达 and others, under the influence of contemporary Soviet ideology, authored a series of articles in which they equated formal logic with idealism on one side, and metaphysics as the counterpart of dialectics on the other. In their writings, the authors even demanded that the status of formal logic as an academic discipline or science should be revoked. Similar views were also upheld by Mao in the first edition of his classic work "On Contradiction" (Maodun lun 矛盾论; 1937), but were later deleted from the subsequent editions of the text. In 1954, Ma Te 马特 published the short booklet entitled On the Rudimentary Rules of Logical Thinking (Lun luoji siwei de chubu guilü 论逻辑思维的初步规律), in which he maintained that while formal logic represents an inferior form of logic, dialectical logic represents an advanced form, and thereby rekindled the great polemic on the relationship between formal logic and dialectics. Later, in 1956, Zhou Gucheng 周谷城 published an article entitled "Formal Logic and Dialectics" (Xingshi luoji yu bianzhengfa 形式 逻辑与辩证法), in which he advanced his theory of "master and subordinate": dialectics is the master and formal logic its subordinate; although the master and subordinate differ from each other, they can never be separated. This theory posed a direct challenge to the "theory of inferior and advanced". Consequently, Zhou's article not only gave rise to a great controversy, but also attracted the attention of Mao Zedong. As a consequence, Mao read many articles that were published in the framework of the then polemics on logic, and also personally convened several public conferences on the topic, calling for their conformity with the official motto "let a hundred flowers bloom and a hundred schools of thought contend" (baihua qifang, baijia zhengming 百花齐放，百家争鸣), and expressing his own support for the ongoing great debate on questions of logic. On November 4, 1957, Mao invited a group of philosophers and logicians to join him at Zhongnanhai 中南海, the headquarters of the Communist Party of China, to conduct a discussion on the questions about logic. Among the invited scholars were Jin Yuelin, Zhou Gucheng, Wang Fangming 王方名, and Huang Shunji 黄顺基. Before and after that event, Mao also met on many occasions with his friend Zhou Gucheng, together with whom he investigated the problematics relating to logic and whose views he also often openly supported (see Xu 2018; Feng 2007). By virtue of Mao's participation, and under his support or even leadership, the great debates on the questions about logic were not only conducted in an atmosphere of extreme enthusiasm, but also continued for many years. The pertinent papers that were published in that period in Chinese periodicals were later collected in three major volumes of The Anthology of Discussions on the Questions about Logic (Luoji wenti taolun ji 逻辑问题讨论集), and published in the years 1959, 1960, and 1962 by the Shanghai People's Publishing House.
The principal questions about logic that were put under discussion in the 1950s and 1960s-such as the relationship between formal logic and dialectical logic, the object, characteristics and use of formal logic, the objective foundations of formal logic, the relationship between veracity and correctness in formal inference, the revision, remodelling and developmental directions of formal logic, inductive inference and methods (cf. Wu 1979)-were not at all technical questions of logic in the strictest sense, but rather a set of philosophical questions about logic. I once commented that, on one hand, these debates have positive consequences such as the disassociation of formal logic from idealist philosophy and metaphysics (in contrast to dialectics), and the founding of its basis on Marxist philosophy, whereby it regained legitimacy from the current official ideology, which later enabled it to become disseminated, popularized and regain a certain degree of advancement. On the other hand, the same discussion also produced some negative consequences, such as: 1) Under the Soviet influence, the subject of these discussions was limited almost exclusively to traditional formal logic, while insufficient attention was devoted to the new mathematical logic, which was sometimes even the subject of a rejectionist attitude and criticism. In this way, Chinese research on logic had lost the chance to get back in step with international currents in the field, which critically delayed and slowed down the entire process of its modernization. 2) By filling the pages of logical treatises and textbooks with numerous concepts and categories from philosophical epistemology and dialectics, a wide variety of technical questions of logic, which had originally been philosophically neutral, had also gained an overinflated philosophical label. Thus, instead of being considered as an instrument of philosophy, as had been the case originally, logic became overly dependent on philosophy. 3) In certain segments of the Chinese circle of logicians, it fostered a shallow academic atmosphere, where no concrete or creative research on logic itself was conducted, and where, instead, scholars would commit their work to studying a series of obsolete theoretical questions and engage in irrelevant philosophical chatter (cf. Chen 2000, 9-10).

Two Major Waves of Popularization of Logic in China
In the 1950s and 1960s, as a political leader with absolute authority, Mao Zedong often discussed or even stressed in official party documents that in writing their articles people should conform to logic, and thus that the cadres employed by the Party and government administration ought to study logic. Following his public appeals, the cadres and young students set off a surge in studying logic, thus forming the first major wave of popularization of logic in China. At that time a few relevant groups were established in the country, which focused on selecting and reprinting Chinese and foreign treatises on logic that had previously been published in Chinese. In 1977, under the presidency of Deng Xiaoping, the entrance system was reinstated in Chinese universities. Consequently, in the following year, Chinese universities welcomed the first generation of students after the Cultural Revolution to have been accepted in their studies by virtue of their final college exams. In the same year, the state re-promulgated the official appeal to "March towards science" (xiang kexue jinjun 向科学进军), causing the generation of youth to long for new knowledge and making the reading of books a common trend in the entire Chinese society. Still under the influence of Mao, at the time almost all university students, no matter whether focusing on the humanities or on natural sciences, were obliged to take a course in logic. As a learning requirement for those who were unable to enter universities, the state set up the Self-Taught Higher Education Examinations for adults, where, in many fields of study formal logic was listed as a compulsory subject. In 1981, Peng Yilian 彭漪涟 and Yu Shihou 余式厚 co-authored the book Fun with Logic (Quwei luojixue 趣味逻辑学), which focused on explaining logical principles by telling stories, and offered a great degree of accessibility for the common reader, because of which the book was widely welcomed in Chinese society. Until this day, I still clearly remember the joy and delight with which I read this book.  Ma 1997), which sold very many copies. Apart from the regular university studies and selfstudy higher education examinations for adults, there also existed various forms of non-governmental schools, the most wide-ranging and influential of which was the China Correspondence University of Logic and Languages (Zhongguo luoji yu yuyan hanshou daxue 中国逻辑与语言函授大学). According to the introduction from its official website, this university was opened in 1982 and has now educated more than half a million students, the majority of whom specialized in formal logic. From the 1980s until the start of this millennium, logic training classes for self-taught examinations blossomed all over the country, so that even university teachers in logic started teaching logic at various places outside of their universities to make more money. At the same time, the sales of books on logic skyrocket; some of them easily sold in tens or even hundreds of thousands of copies, while some sold in the millions. We can call this stage the second major popularization of formal logic in China.
On a brief note, allow me to mention that, in the following years, two of my own books on logic have also proved very effective in disseminating and popularizing knowledge in this field: the first was entitled What is Logic? (

The Development of General Education in Logic at Chinese Universities
The development of teaching logic at Chinese universities in the period between 1949 and 2019 can be clearly divided into two stages, that is, before and after Deng Xiaoping's reforms and the opening of China to the outside world. Considering the importance of logic education, in the following paragraphs we shall cast some light on this development by means of a relatively extensive overview of the logic textbooks used in PRC in the above-mentioned two periods.
In the 1960s, due to its close relations with Soviet academia, the Renmin University of China ("RUC" for short) (Zhongguo Renmin daxue 中国人民大学) became a major centre of Chinese higher education. Already back in 1958, the university's teaching and research section for logic compiled the work Formal Logic (Xingshi luoji 形式逻辑), whose content is quite close to that of the Soviet logic textbooks. It consisted of twelve chapters, as follows: "Introduction"; "On the Object and Meaning of Formal Logic"; "Concepts"; "Judgments"; "The Fundamental Laws of Formal Logic"; "Inference"; "Direct Inference"; "Categorical Syllogisms"; "Hypothetical and Disjunctive Syllogisms"; "Inductive Inference"; "Analogy and Hypothesis"; "Proof ". In addition to these, the chapter on judgments was also followed by an appendix on the expression of concepts and judgments in Chinese language. Thereafter, investigation of special manifestations and applications of traditional formal logic in the Chinese language became one of the main special features of logic textbooks compiled at RUC. Later, the book was reprinted several times. The second edition appeared in 1980, and the second revised edition in 1984. Even though the contents in the second edition were still almost the same as in the first, the second contained two additional appendices: "Logical Analysis of Argumentative Treatise" and "A Brief History of Logic". As pointed out by Zhuge Yintong 诸葛殷同, "having had an immense circulation within the country, these two volumes produced a profound and long-lasting impact" (Zhuge 1997, 151).
In 1962 Jin Yuelin took charge of the compilation of the textbook Formal Logic (Xingshi luoji 形式逻辑), which was intended for use in the humanities at national colleges and universities. Other scholars who took part in creating the work were mostly senior Chinese experts in logic, like Wu Yunzeng 吴允曾, Zhou Liquan, Yan Chengshu 晏成书, Zhuge Yintong, and so on. The final version of the first draft of the book, which was completed by the following year, was later compiled by Zhou Liquan and reached its final form in 1965. However, due to the breakout of the Cultural Revolution, the launch of the book was postponed until 1979, when it was finally published. Although this book is essentially limited to traditional formal logic, its content was considerably expanded in comparison with the above-mentioned Soviet textbooks. It consisted of the following seven chapters: "The Object and Uses of Formal Logic"; "Concepts"; "Judgments, Involving Categorical, Relational, Compound, and Modal Judgments"; "Deductive Inference, Including Direct Inference, Syllogisms, Relational Inference, Inference of Compound Judgments and Modal Inference"; "Inductive Inference"; "The Fundamental Laws of Formal Logic, Focusing Only on the Laws of Identity, Contradiction and the Excluded Middle, and not Mentioning the Law of Sufficient Reason"; "Argumentation, Discussing Both Proof and Refutation". The book also contained one appendix on resources in the history of logic. Overall, this textbook is an example of an outstanding work on traditional formal logic, whose major and most important features are the conciseness of its content, the precision of its exposition on the subject, the elegant and succinct writing style, carefully selected examples, and meticulously designed selection of exercises. Back in those years I conscientiously read the book several times and completed each and every exercise contained therein, establishing the initial foundations of my knowledge and technical mastery of logic using this book.
After the end of Cultural Revolution in 1976, China embarked upon an entirely new path. In May 1978, a nationwide symposium on logic was held in Beijing, at which Zhang Jialong 张家龙 presented his report entitled "Modernization of Formal Logic" (Xingshi luoji de xiandaihua 形式逻辑的现代化), in which he raised his critique of several problems in teaching material on traditional logic in Chinese national education. Moreover, in his report Zhang proposed enriching and developing traditional logic with modern logic by compiling a new generation of logic textbooks that would incorporate the spirit, content, and methodology of modern logic. At the second national symposium on logic, in August 1979, Wang Xianjun gave a lecture entitled "Modernization of Logical Curricula" (Luoji kecheng de xiandaihua 逻辑课程的现代化), in which he proposed the universal reform of academic programs and courses in logic offered to students of the humanities at Chinese colleges and universities, that is, to modernize their contents. Subsequently, the policies favoured by Zhang and Wang gave rise to an intense debate on the "modernization of logic" that went on for more than ten years. In the course of debate, three main positions on how to modernize logical curricula were formed: the first was the "theory of replacement", that is to replace traditional formal logic with mathematical logic; the second was the "theory of assimilation", that is to assimilate some contents from mathematical logic into the framework of traditional logic; and the third was the "theory of coexistence", which maintained that traditional formal logic on one side and mathematical logic on the other both have their advantages and both are needed, and must therefore be offered separately while maintaining a harmonious coexistence. Following a few decades of development, the ultimately prevailing form of teaching material are the textbooks on "introductory logic", combining both traditional and modern logic.
The most successful textbook in the category "theory of assimilation" is the work General Logic (Putong luoji 普通逻辑), edited by Wu Jiaguo. This was the main textbook in logic for studies in the humanities at national colleges and universities, the compilation of which was organized by the Ministry of Education. It was composed by eleven renowned teachers of logic from various Chinese universities, while the compilation of the final manuscript was done by Wu Jiaoguo. The book was finally published in 1979 by the Shanghai People's Publishing House. Afterwards it underwent three revisions, having been released in four different editions, each time incorporating more and more contents related to modern logic. In 1995, the book was awarded the "First Prize of the Third Awards for Excellent Textbooks in General Higher Education" by the National Education Committee. The total number of copies printed to date has probably exceeded three million, which testifies to the extensive use and huge influence of this book. Wu later wrote an article speaking about the guiding ideas behind the compilation of this textbook: The bulk of general logic must consist of the quintessential features from traditional logic, and must be suitable for absorbing the basic knowledge of mathematical logic, forming a teaching system combining the two kinds of logic; logical form must not only include deductive but also inductive inferences; the rules of syllogism can be divided into structural rules, general rules and rules of derivation, which differ from each other in their respective level; the scopes of application of laws of contradiction and excluded middle possess no distinction in broadness and narrowness; the law of sufficient reason can be retained, but not as a universal logical law but as a law of argumentation; in argumentation, the methods and rules of proving need to be harmonised with each other in order to eliminate logical contradictions. (Wu 2004, 117) As a result of Deng Xiaoping's reforms, the circle of Chinese logicians started gradually gaining greater familiarity with the situation in logic education in the West. Consequently, a few textbooks written in English soon became the subject of serious study by a certain group of Chinese logicians. Under the planning and preparations of myself, three textbooks on logic, widely used at Western universities, were translated into Chinese and published: the eleventh edition of  (2013)).
Under the influence of Western logic textbooks, a succession of work of the type "an introduction to logic" were compiled and published in China. The first noteworthy such textbook was the New Course in Logic (Xin luoji jiaocheng 新逻 辑教程) edited by Song Wenjian 宋文坚 and authored by Zhou Beihai 周北海, Liu Zhuanghu 刘状虎, Li Xiaowu 李小五, Deng Shengqing 邓生庆 and others, which was published in 1992. In this work prominence is given to a framework set around modern logic, focusing mainly on elaborating the basic content of modern deductive and inductive logics. It consists of the following nine chapters: "The Object, Methodology, and Meaning of Logic"; "Formulae, Truth Tables, Normal Formulae, and Formal Proof of Propositional Logic"; "Propositional Calculus"; "Traditional Predicate Calculus"; "Formulae of Predicate Calculus"; "Operations, Inference and Proofs in Predicate Logic"; "Modal Logic"; "Naïve Set Theory"; "Inductive Logic". Based on this textbook, a group of members of the teaching and research section for logic at Peking University compiled another book, Logic (Luojixue 逻辑学), the compilation of which was supervised by Song Wenjian as editor-in-chief and Guo Shiming 郭世铭 as assistant editor. This book, which was first published in 1998 by the People's Publishing House, consisted of seven chapters: "Preface; "Propositional Logic"; "Categorical Logic"; "Monadic Predicate Logic"; "Predicate Logic"; "Inductive Logic"; "Logical Methods". In addition, the book also contains an appendix: "A Brief Introduction to Applied Logic, Introducing Modal Logic, Temporal Logic, Intuitionist Logic, Many-Valued Logic, and Free Logic". In comparison with other textbooks, these two volumes already contained a considerable amount of modern logic, and hence also the most systematic, thorough, and accurate exposition of the principles and methodology of modern logic. However, for this reason it was only rarely put to use at Chinese universities.
Between 1984 and 1992, during my tenure in the teaching and research section for logic at RUC, and under my participation and even guidance, my colleagues at that section compiled a textbook entitled Logic (Luojixue 逻辑学). The book, which was first issued in 1996, included the following eight chapters: "Preface"; "Propositional Logic"; "Categorical Logic"; "Modal Logic"; "Inductive Logic"; "The Fundamental Laws of Logic"; "Proof and Refutation"; "Fallacies". This book belongs to the "integrative type" of textbooks on traditional logic and modern logic. Its second and third editions emerged in the years 2008 and 2014, having attained fairly wide use at Chinese universities. Later, after I moved to Peking University, I authored a new textbook Introduction to Logic (Luojixue daolun 逻辑 学导论) on my own. The book was published in 2003 and consisted of the following six chapters: "Logic is a Science of Inference and Argument"; "Propositional Logic"; "Categorical Logic"; "Predicate Logic"; "Inductive Logic"; "Informal Logic". Apart from these main chapters it also contained the following appendix: "Formalization Method and Formal Systems". In the years 2006, 2014, and 2020, the second, third and fourth editions of the book were published, from which the above-mentioned appendix was omitted. This textbook not only further approached the Western style of "introduction to logic", but also had extensive use.  (2008)) by the teaching and research section for logic of Nankai University, as well as the Logic (Luojixue 逻辑学 (2017)) volume of the Ministry of Education's "Ma Engineering Project" Key Textbooks ("Ma gongcheng" zhongdian jiaocai"马工程"重点教材) series, which was edited by He Xiangdong, and composed by a large group of Chinese experts in logic.

Teaching and Research of Mathematical Logic
In China, scholars who engage in work on mathematical logic can be divided into two main groups. The first is the Association for Research in Modern Logic attached to the Chinese Association of Logic (Zhongguo luoji xuehui 中国逻辑 学会). The majority of the members of this organisation are concerned with education activities and compilation of teaching material relating to mathematical logic, while only a minority engage in research into mathematical logic in the strictest sense. However, in recent years this group has changed rapidly with the arrival of the younger generation of Chinese logicians. The second is the mathematical logic branch of the Chinese Mathematical Society (Zhongguo shuxue xuehui 中国数学学会). The members of this group engage to a greater extent in research on mathematical logic, but to a much lesser degree maintain contact and communicate with the members of the Association of Logic, causing the latter to be rather unfamiliar with the research of the former. I myself am one of the representatives of the latter, possessing only a vague idea of the state of research and concrete advances in Chinese mathematical logic. The overview of teaching and research of mathematical logic in China is summarized in this article based on two main sources: the first is the chapter 2 on "Mathematical Logic" by Zhao Xishun 赵希顺 in Contemporary Chinese Research in Logic 1949-2009(Dangdai Zhongguo luojixue yanjiu 1949-2009当代中国逻辑学研究 1949-2009 These scholars have produced a great number of international-level research achievements and are all actively engaged in the international frontiers of their fields of research (see Ju 2013, 50-122.). In recent years, in collaboration with Yang Yue and other scholars in Singapore, Hao Zhaokuan 郝兆宽 and Yang Ruizhi 杨睿之 from Fudan University have contributed much to the advancement of research both in set theory and the thought of Kurt Gödel, and also to the compilation of mathematical logic textbooks.

A Period of Flourishing Research in Dialectical Logic
In China, dialectical logic was once generally believed to be a science concerned with studying the forms, methodology, and laws of dialectical thinking. From 1949 to the 1980s, or even up to the early 1990s, represents the period in which dialectical logic flourished in China. In my opinion, this was an aggregate outcome of various different causes: 1) The first resided in the fact that the traditional Chinese philosophy, such as, for example, the Book of Changes (Zhouyi 周易), the philosophy of Laozi and Zhuangzi, Buddhist philosophy and so on, contained a strong focus on the grand narrative of the universe, having paid particular attention to the circulations and changes underlying the various things and phenomena that exist, thinking about the same question from several different angles, striving to refrain from epistemic stiffness, rigidity, and attachment. All these aspects possess a strong resemblance to dialectical thought. 2) German classical philosophy, represented by Kant and Hegel, has had a great influence on China. As a consequence, Hegel's representative works, popularly referred to as "large logic" and "small logic", together with his dialectics of "thesis-antithesis-synthesis", were commonly referred to as "dialectical logic". 3) Marxist philosophy, which inherited and transformed German classical philosophy, is the official ideology in China, and in some of its classical works "dialectical logic" is often mentioned and advocated. 4) The philosophical circles of the Soviet Union, which for a period of time was revered by China as its "big brother", all propagated and studied dialectical logic. Some of the related works were also translated into Chinese,  (1984)). All these works had a great impact on Chinese academia.
In the 1980s and 90s, several Chinese research treatises and even textbooks on dialectical logic were published in China. The domestic research on dialectical logic can be summarized with a list of the following seven research directions: comparative research on dialectical and formal logic; research on the theory of categories; research on the methodology of sciences; research on non-classical logics; dialectical examination of new results on modern logic and philosophy of logic; research on the practical applications of dialectical logic; studies in the intellectual history of dialectical logic (cf. Ju 2013, 375-86). Zhou Liquan's Hegel's Dialectical Logic (Heigeer de bianzheng luoji 黑格尔的辩证逻辑; 1989) is a representative contribution in the framework of the last kind of approach. Although within the framework of these studies there also emerged many valuable insights and achievements, generally speaking, due to unclear distinctions between dialectical logic and dialectical materialism, the logical colouration of their results was rather weak, which is also why they have not attained wide recognition or approval. Consequently, since the beginning of the 21st century, dialectical logic has gradually withdrawn to the fringes of the Chinese academic world, to the degree that it is today very difficult to detect any signs of its presence.

Continuous Advance of Research in the History of Chinese Logic
In my opinion, between the years 1949 and 2019, in comparison with other branches of the science of logic, the history of Chinese logic is a field of research which made significant progress and attained plentiful results in China, and, at the same time, is still brimming with controversies and enthusiasm. I concur with the following generalizations: in this period of time research in history of Chinese logic can be roughly divided into three periods, namely, the opening period of research in history of Chinese logic in the first 17 years since the founding of PRC, the period of scientific construction of history of Chinese logic in the 1980s, and the period of deepening and reassessment of the research in history of Chinese logic from the 1990s up to the present day. … the differentiating feature between the second and third period was marked by the publication of the key item History of Chinese Logic (five volumes) in 1989, which was commissioned in the framework of the national Sixth Five-Year Plan. On the other hand, while the main subject of the former period consisted in founding history of Chinese logic as an academic discipline, in the latter period equal stress was laid both on research and reassessment, in the course of which several different positions on Chinese logic took shape. ( Ju 2013, 396) The representative achievements of the first period include the following publi  (1961)) as well as a series of his articles from the period under discussion (cf. ibid., 399).
Below we will focus our discussion on the last two periods of studies on the history of Chinese logic. Attempts to answer questions such as how we should actually carry out research on the history of Chinese logic, what kind of interpretational frameworks should be adopted, gave rise to controversies and disagreements among different researchers, and especially among different generations of researchers, and in turn also to several different approaches. By and large, however, we can distinguish between two major approaches, as follows.
The first approach chose from certain Western (in a narrow or general sense) theories of logic-such as, for example, traditional formal logic, mathematical logic, informal logic, theories of argumentation or semiotics-to serve as the interpretational framework for the relevant logical material in Chinese classics. These background theories were thus used to reconstruct ancient Chinese logic, while judgments were then made by means of comparative research on the advantages and disadvantages of such logics. For the most part, the scholars furthering this kind of approach emphasized the generality of human thought and universality of logical theories, making use of Western theories of logic in their hermeneutics of Chinese classics, and closely pursuing the ideas of unity, resemblance, and fusion between Chinese and Western theories of logic. As the framework of their interpretations, some scholars chose Western traditional formal logic, while some of them even went as far as to choose ideas, methods, and techniques from modern mathematical logic. The representative achievements of this kind of research include the monumental five-volume work History of Chinese Logic edited by Li Kuangwu 李匡武 (1989), which was an achievement of one of the key-pro-  (2017)).
The second approach strives to emphasize the interrelatedness between logic and culture, advocating the use of comparative methods founded on "historical analysis and cultural hermeneutics" in our attempts to interpret and construct ancient Chinese logic on the basis of the original characteristics of Chinese culture. This approach gives prominence to the differences in modes of human thought and particularities of logical theories within different cultures, opposing the attempts at forcefully inculcating Chinese logical material into the framework of Western logic and using the later for drawing oversimplified parallels between the two. The majority of the proponents of this approach have earned their doctorates under the scholarly influence of Professor Cui Qingtian 崔清田 at Nankai University, who is considered to have been the nucleus of formation of the "Nankai School" of studies in the history of Chinese logic. 3 Cui maintains that: Logic is the science of the structure and form of logical thinking, which is influenced by culture. It not only possesses logical commonalities but also particularities. With commonalities we refer to fixedness of the nature of logic, of which the common object is the most elementary. Particularities, on the other hand, designate those features of logic that appear within different historical and cultural contexts, such as the differences between prevailing types of inferences, as well as the discrepancies between the methods of formulating forms of inferences. Taking this kind of view on logic as a precondition and foundation, one can disapprove of the view that Western traditional logic and modern formal logic are the only kind of logic, recognising those logics that derive their differences from their cultural backgrounds and possess their own characteristics. Hereby we can also confirm that "Chinese logic" is a form of learning within Chinese national learning and was not merely discovered within Chinese studies of Western logic. "Chinese logic" thus contains commonalities identical to those of Western science of logic, while at the same time also possesses particularities which differ from those of the latter. (Cui 2011, 49) The principal achievements obtained in this way posit that Chinese ancient logic constitutes the science of names and science of disputation that are different from traditional formal logic, of which the latter uses "tuilei 推类" as the leading type of inference. Moreover, its tuilei has got the characteristics of analogical reasoning and belongs to probabilistic inferences.  (2017)) by Zeng Zhaoshi 曾昭式.
Following the path of emphasizing the interrelatedness of logic and culture, Ju Shier went even further, positing that logical theories are influenced by different elements such as cultural factors, social environment, motivations of the cognitive subject, etc. The logic of different cultures is thus bound to possess different characteristics; maybe it could even be claimed that different cultures are also likely to have different logics. Moreover, cultural relativism and logical diversity cannot be tolerated by the formal and informal logics which can be found in Western tradition. Ju also proposed a general theory of argumentation, advocating its application as the framework for the reconstruction of history of Chinese logic (see Ju 2010). Working with his PhD students, Ju published a series of research articles advancing this kind of approach, although no systematic monograph has yet been published on the topic.
Here it also needs to be mentioned that in the last ten years several other monographs have been published which summarized and reassessed Chinese logical studies over the course of the last century.  (2007)), and the monograph Boring into Hetuvidyā (Yinming lice 因明蠡测 (2008)). At the beginning of the 21st century, hetuvidyā was included in the national plan of "rescuing disappearing sciences" (qiangjiu juexue 抢救绝学), and has since received enormous support. As a result, many newly graduated doctors of philosophy engage in research on hetuvidyā, and this field of studies is experiencing great enthusiasm, with many thriving areas of work.

The Lonesome Advance of Studies in the History of Western Logic
Compared with the research on the history of Chinese logic, it appears that Chinese studies on the history of Western logic have never reached the same level of popularity. Accordingly, the number of scholars who continue pursuing this field has remained relatively low, yet at the same time they have also seen considerable achievements and made quite significant progress.
In the period before the Deng Xiaoping reforms, systematic research on the history of Western philosophy was still rare in China. As a rule, "a brief history of logic" could only be found in logical textbooks, often only in the form of appendices. In this period, a few treatises on history of logic were translated into Chinese, such as  (2016b)). Among these, the book Developmental History of Logic represents China's first comprehensive and systematic treatise on the history of mathematical logic from Leibniz to Gödel. In its opening parts, the book enumerates the methodological principles for research on the history of mathematical logic, dividing its development into four main periods: prehistory, the early stages, foundation and development. The book further expounds on these stages by adopting principles such as integrating logical method and historical method, concluding with illustrating both the external moving forces and internal patterns of the development of mathematical logic, and casting some new light on the dialectical relationship between mathematical logic and social practice. In the discussion on the major results of mathematical logic, particular emphasis was placed on the analysis of logical methods, and, furthermore, on providing a general overview and summary of the philosophical significance of these important results.

Sustained Deepening of Research into Inductive Logic
According to the research conducted by Ren Xiaoming 任晓明 and others (Ren, Li, and Cheng 2010), soon after modern inductive logic had been introduced to China in the 1980s, Chinese research on this underwent a change of its direction from classical to modern inductive logic. A further three major changes of direction at the secondary and primary levels are as follows: a turn from informal research to formal research as well as the synthesis of formal and informal research; a shift from inductive logic of causal relations to probabilistic inductive logic; and a shift from Pascalean probability to non-Pascalean probability.
The key role in advancement of the research on inductive logic in China was played by Jiang Tianji (1915-2006. Its origins can be traced back to 1984, when Jiang delivered a series of lectures on modern inductive logic in Shenyang 沈阳. One year later, in 1985, Jiang published an English article entitled "Scientific Rationality, Formal or Informal?" in The British Journal for the Philosophy of Science ( Jiang 1985). This was followed by the publication of his Chinese monograph An Introduction to Inductive Logic (Guina luoji daolun 归纳逻辑导论) in 1987, in which he provided a systematic discussion of modern inductive logic. During the 1990s, Jiang published a further series of Chinese articles on modern inductive logic. Apart from that, he also influenced his colleague Gui Qiquan 桂起权 and served as a doctoral supervisor to a number of future experts (including Zhu Zhifang 朱志方, Chen Xiaoping 陈晓平, Ren Xiaoming, and Pan Tianqun 潘天 群). Furthermore, following Jiang's initiative many colleagues from other Chinese universities also shifted their research to inductive logic, and finally a school of research on inductive logic was formed by those scholars gathering around Jiang.
Another important scholar to have made significant contributions to Chinese research on inductive logic was Wang Yutian 王雨田 (1928. He was in charge of the research team focusing on problems of inductive logic and artificial intelligence in the framework of the National 863 Project, and served as the editor-in-chief of the monographs Introduction to Inductive Logic (Guina luoji daoyin 归纳逻辑导引 (1992)) and Inductive Logic and Artificial Intelligence (Guina luoji yu rengong zhineng 归纳逻辑与人工智能 (1995)) that were part of the same project. Furthermore, Ju Shier's work Studies in Non-Pascalean Inductive Probabilistic Logic (Fei-Basika guina gailü luoji yanjiu 非巴斯卡归纳概率逻辑研究 (1993)) can also be counted as one of the main accomplishments of Chinese studies on inductive logic. In this book, he systematically analysed G. Shackle's potential surprise theory and Cohen's theory of inductive support and grading of inductive probability, establishing his own formal system of non-Pascalean probability-a system of syntax about hypotheses with law-like degree.  (2006)).
In his English paper from 1993, Ju Shier demonstrated the insolvability of Hume's problem of induction within the scope of logic, or, in other words, that in logic there is no way to provide neither a positive nor a negative answer to the problem. Outside of the scope of logic, he advanced the concept of local rationality and the method of local justification of induction, attempting to use them to explain how a local justification, rejection or suspension of inductive rationality is possible. Furthermore, he also provided the reconstructive procedure of local induction of scientific research. In a 2001 article, I demonstrated that the background of Hume's problem implicitly contains three unfounded presuppositions: Hume accepted a universal necessary notion of knowledge, having not only looked for deductive necessity but also wanting to explain the necessity of causal relations and universality of empirical knowledge under the confines of sense experience. Since these conditions stand in mutual conflict with each other, this renders Hume's problem essentially logically insoluble. Finally, I also put forward an argument for inductive reasoning based on the concept of practical necessity, proposing a comprehensive program for research on inductive logic (Chen 2001 (2010)). In the last few years, and in cooperation with her doctoral students, Tang Xiaojia has done much high-standard work relating to the logical aspects of game theory and decision making. In a recently published article (Tang 2018), starting from the perspective of the questions "what are the requirements of research in theory of decision making?" and "what can be done with modern logic", she discusses the multifarious practical value of modern logic in research on decision making theory: it can provide linguistic tools for formally characterizing research on decision making, and defining the algorithms for decision making on the basis of such characterization, describing and demonstrating the strategic capability of the subject, and revealing the difficult problems and predicaments with which we are confronted in the process of decision making, and assisting us in the search for the way to resolve such difficulties. She further urged logicians to engage in research on decision-making theory and join efforts of the related experts to resolve various kinds of challenges that arise in the process of rational decision-making. In this very process, logical knowledge can not only promote the development of decision-making theory, but also promote the establishment of new logical theories and technologies.

The Rise of Research on the Logic of Natural Languages
In the period between the 1960s and the early 1990s, in a community of scholars represented by Wang Fangming, Zhang Zhaomei 张兆梅, Sun Zupei 孙祖培, and others, special attention was devoted to research on the special manifestations and application of traditional formal logic in the Chinese language. Representative research in this regard includes Sun Zupei's Essay Writing and Logic (Wenzhang yu luoji 文章与逻辑 (1986)), and Chen Zongming's reputed work Logic in Talking and Essay Writing (Shuohua xie wenzhang zhong de luoji 说话写文章中的逻辑 (1989)).
Zhou Liquan (1921Liquan ( -2008 has contributed immensely to Chinese studies on the logic of natural languages ("LNL" for short). In the 1960s, he began to research novel theories such as the speech act theory as advanced by J. L. Austin and J. R. Searle, the theory of conversational implicature by H. P. Grice, as well as other important issues relating to semantics and pragmatics, and thereby introducing the novel wave of research on LNL into Chinese academia. In China, the so-called "logic of natural languages" refers to the logical science which studies the inferences in natural languages through linguistic designation and communication.
During the 1960s, Zhou published one article to demonstrate that formal logic ought to investigate the concrete meaning of expressions in natural languages under specific contexts. From the 1980s onwards, he also advocated the view that research on LNL ought to be conducted on the joint theoretical basis of modern logic, modern linguistics and rhetorics, emphasizing that by using modern logic in the analysis of natural language a new system of logic could be created, whereby the use and scope of logical theory would be expanded and enriched, providing a more effective tool for everyday human thinking and communication. In his 1994 work Logic-A Theory of Correct Thinking and Successful Communication (Luoji -Zhengque siwei he chenggong jiaoji de lilun 逻辑--正确思维和成功交际的 理论), Zhou attempted to implement these positions. This book distinguishes between three different levels of pragmatics: formal, descriptive, and applied. In his opinion, epistemic logic, deontic logic, logic of commands, logic of questions and so on all belong to the category of formal pragmatics. In contrast, concepts such as context, speech act, conversational implicature, presuppositions and rhetoric belong to descriptive pragmatics. Finally, acts like speech, lecturing, debates and their interrelated contents all belong to the domain of applied pragmatics. Furthermore, he also developed the theory of four-level meanings for four different forms of sentences, that is, proposition for abstract sentence, propositional attitude for sentence, significance for discourse, intension (yisi 意思) for discourse in a context of communication. Under his direct guidance and influence, there appeared two further generations of young Chinese logicians who also focused their research on LNL.
The first generation of researchers in LNL includes Wang Weixian 王维贤, Li Xiankun and Chen Zongming, whose cooperation resulted in a joint monograph entitled Introduction to Logic of Language (Yuyan luoji yinlun 语言逻辑引论 (1989)), which represents the first specialized monograph on the topic of LNL in China. Apart from this monumental monograph, each of these scholars also individually authored books on the same topic.  (2002)). Cai Shushan's research, on the other hand, is mostly concerned with speech act theory and illocutionary logic, aiming to further develop the work of Austin and Searle, and subsequently establish a formal system of illocutionary logic. He has published two books in LNL: Speech Acts and Illocutionary Logic (Yanyu xingwei he yuyong luoji 言语行为和语用逻辑 (1998)), and Language, Logic and Cognition (Yuyan, luoji he renzhi 语言、逻辑和 认知 (2007)). Huang Huaxin primary research interests involve topics from cognitive pragmatics, such as pragmatic presuppositions, metaphor, and discourse. He has co-authored several specialized monographs, including Descriptive Pragmatics (Miaoshu yuyongxue 描述语用学 (2005) Finally, the third generation of researchers on LNL are still in the process of formation. Currently, the most prominent among them is Liao Beishui 廖备水, who in his work integrates research on the discourse of natural languages and their logic with artificial intelligence research, taking part in high-level international research cooperation. So far, Liao has published a great number of internationally pioneering research results.

The Import and Flourishing of Philosophical Logic
According to my own detailed examination (cf. Chen 1997), in Western academia philosophical logic came into vogue in the period between the 1930s and 1940s, while in the period since the 1950s up to the present it still represents a vigorously developing and newly ascending group of different branches of logic. It takes mathematical logic (mainly first-order logic) as its direct foundation, while it takes as the objects of its research traditional philosophical concepts and categories on the one hand, and the application of logic in various concrete sciences on the other. As a research field it thus aims to construct different kinds of logical systems with direct philosophical significance. The group of philosophical logics can be divided into two subgroups: the first is deviant logics, formally manifested as alternative systems of classical logic, including relevance logic, intuitionist logic, free logic, partial logic, logic of counterfactuals, many-valued logics, quantum logic, and fuzzy logic, among others; the second is applied logic, formally manifested as expanded systems of classical logic, such as modal logic, deontic logic, temporal logic, epistemic logic, logic of interrogatives, logic of commands, logic of preference and so on (see also Chen 2013, 13).
Since it is practically impossible to give a comprehensive and precise overview of Chinese studies in such a vast and extensive field in a short study like the present one, here I will try to sketch the whole picture by presenting the work of several representative scholars in the field.
Since the 1980s, a series of introductory works, textbooks, and research treatises on philosophical logic have been published in China. These, for example, include  (2003)). The former, which was co-authored with Guo Shiming and Li Xiaowu, offers a relatively systematic and accurate exposition of first-order logic, modal logic, temporal logic, logic of conditionals, many-valued logics, relevance logic, intuitionist logic, paraconsistent logic and Gödel's incompleteness theorems. Zhang obtained a series of significant results in the field of paraconsistent logic.
On the basis of his penetrating analysis of da Costa's system of paraconsistent logic, he constructed systems of paraconsistent logic of conditionals PIW, C n W, paraconsistent modal logic C n G¢, paraconsistent logical systems Z n and Z n US, minimal paraconsistent systems of temporal logic with operators G and H, and minimal paraconsistent systems of temporal propositional logic with operators U and S, all of which together expanded the research direction of paraconsistent logic, enriched the theoretical systems of such logics, and thereby advanced Chinese research-level in this particular type of logic ( Ju 2013, 153).
In the field of philosophical logic, Feng Mian 冯棉 primarily researched relevance logic, intuitionist logic and modal logic. As a prolific writer, he authored a wide collection of books: Classic Logic and Intuitionist Logic (Jingdian luoji yu zhijue zhuyi luoji 经典逻辑与直觉主义逻辑 (1989) In 1999, Zhou Beihai published an article in The Journal of Symbolic Logic, in which he established a new type of semantic framework for modal logic-grafted frames-proving the completeness of the system of modal logic S1. In 2010, together with Mao Yi 毛翊, Zhou cowrote an article which was published in the internationally acclaimed journal Synthesis, and in which the authors provided four semantic layers of common nouns.
Liu Fenrong's 刘奋荣 research mainly involves the logic of rational agency. In her work, Liu has developed several models to explain how information dynamically transforms the preferences of individuals and other agents. In her book Reasoning about Preference Dynamics (2011), which was originally written in English as her dissertation at the University of Amsterdam, she developed a new integrated theory using modern information flow and action logic, explaining what exactly preference is and how it changes. She also proposed systems of dynamic logic, which describe the external conditions that act as triggers for the transformation of preference, including new information, suggestions, and commands. Most importantly, this work built new bridges connecting several different scientific disciplines (from philosophy and computer science to economics, linguistics, and psychology), and thus garnered wide influence across the fields. In her current work she focuses on the logical analysis of information flows and decision making within social contexts, where her analysis encompasses both individual subjects as well as social groups. She herself is well recognized by her international colleagues in contemporary logic circles.
Wang Yanjing's 王彦晶 research revolves around epistemic logic. He has published numerous articles on the topic in internationally influential A&HCI journals. In recent years, he proposed and advanced an integrative research project for the field of epistemic logic-the logic of "knowing whether/how/why/what/ who"-that would thus surpass the standard epistemic logic of "knowing that" (knowing a single proposition) (cf. Wang 2018).

Gradual Flourishing of the Philosophy of Logic
In the 1980s and 1990s, Susan Haack's book Philosophy of Logics (1978) became widely read among the younger generation of Chinese logicians, and thus the philosophy of logic started to become well known in the Chinese circle of logic.
According to my own research, the philosophy of logic aims to reveal the implicit fundamental hypothesis, background assumptions or preconditions underlying general logic or specific logical systems, and to challenge their rationality and investigate the possibilities of alternative choices. There exist at least two different perspectives from which one can approach philosophy of logic: epistemological and ontological (Chen 2013, 17).  (2014)) presented an exhaustive investigation of paradoxes, providing a relatively in-depth research of a wide array of different paradoxes. Since 2007 I have authored more than 20 English articles which were published in different international A&HCI journals, the majority of which were devoted to the philosophy of logic.
In his book The Conception of Logic (Luoji de guannian 逻辑的观念 (2000)), Wang Lu posits that logic exclusively describes a science investigating the relation of "necessary follow" of conclusions from certain premises, while other types of socalled "logic", for instance "inductive logic" or "dialectical logic", are not at all true logics, because their focus does not reside with the relation of "necessary follow". The book initiated to a wide-ranging and intense polemic regarding the following questions: What is logic? How should we investigate logic? Was there in ancient China such a thing as logic? How should we approach the history of Chinese logic? How should we study Western philosophy? Wang wrote another book entitled Being and Truth: The Cornerstones of Metaphysics (Shi yu zhen: xing er shang xue de jishi 是与真：形而上学的基石 (2003)), which explores the philosophical significance of "to be" and "truth" as well as their corresponding terms in Chinese, which also gave rise to fierce debates in the fields of logic and philosophy.
Zhang Jianjun was the first Chinese scholar to have systematically studied logical paradoxes, whose principal interest resides in mathematical and semantic paradoxes. He has published several different book about paradoxes, of which the most influential is his Introduction to Studies on Logical Paradoxes (Luoji beilun yanjiu yinlun 逻辑悖论研究引论; first published in 2002, a revised edition published in 2014). In this book, he discusses the constituents and classifications of paradoxes, as well as the origins and characteristics of different paradoxes. Additionally, he has also conducted comparative research of different kinds of solutions for paradoxes, exploring the standards of correctly eliminating paradoxes, and at the same time distinguishing between different hierarchies of researching paradoxes and their mutual interactions. He has also edited the collective monograph Studies in Frontier Problems in Contemporary Philosophy of Logic (Dangdai luoji zhexue qianyan wenti yanjiu 当代逻辑哲学前沿问题研究 (2014)), which clarifies and evaluates the advances in the Western philosophy of logic since the 1970s.
In their co-authored book Genetic Research of Non-Classic Systems of Logic (Fei-jingdian luoji xitong fashengxue yanjiu 非经典逻辑系统发生学研究 (2011)) Ren Xiaoming and Gui Qiquan carried out a genealogical investigation of non-classical logical systems, such as modal logic, intensional logic, deontic logic, the logic of indicative conditionals, inductive probability logic, fuzzy logic, quantum logic, many-valued logics, paraconsistent logic, formalized dialectical logic and the logic of argumentation. From their investigation, they drew the following conclusions: the central question of the philosophy of logic is the question of an exact match between the concepts of system-relative and extra-systematic validity of inference. As they emphatically noted: … in contrast to the academic world of philosophy of science, where a climate of fallibilism has already taken the upper hand, in the current Chinese circle of logicians the influence of epistemic inerrancy is still standing strong. It is highly probable that this has turned into a great intellectual impediment for Chinese logic's "reform and opening up"! Its reform ought to be done with greater courage and at a more rapid pace! A new practice would inevitably open up new ground for logic and help it to rapidly overcome the old delimiting norms. People must in no way stop marching onwards on hearing the warning "not logic". To make innovations in logic scholars must be adept at turning the philosophy of logic into a weapon, encouraging the departure from various kinds of classic systems and bring about a contest between oppositions, to finally pave the way for the emergence of new non-classic logics! (Ren and Gui 2011, 222) Focusing on theories of truth, free logic, and their philosophical characteristics, Hu Zehong composed two books on the philosophy of logic: Rethinking Philosophy of Logic (Luoji de zhexue fansi 逻辑的哲学反思 (2004)) and Studies in Philosophy of Logic (Luoji zhexue yanjiu 逻辑哲学研究; Hu et al., 2014). The work Studies maintains that the philosophy of logic is a scientific discipline which studies logic, in particular modern logic and the philosophical questions of its development. The book consists of an introduction and the following nine chapters: "The Scope and Characteristics of Logic"; "Logic, Language, and Existence"; "Truth and the Theories of Truth" (two chapters); "Meaning and Reference"; "Modal Logic and its Philosophical Questions" (three chapters); and "Free Logic and its Philosophical Questions". The first five chapters represent a comprehensive philosophical investigation of logic, with a particular focus on modern logic, whereas the last four chapters select two concrete branches of modern logic, namely modal logic and free logic, presenting a relatively in-depth investigation of their inherent philosophical questions.
In the recent years, Li Na 李娜 and her PhD students have conducted systematic research on axiomatic theories of truth, which covered classical axiomatic theories of truth, as well as axiomatic theories of truth based on intuitionism and set theory. Collectively, they have published several quite high-quality papers, and their achievements of the project supported by the National Social Science Fund were evaluated as "excellent".
Xiong Ming's 熊明 research focuses mainly on truth theory and liar-type paradoxes, on which he published a book entitled Arithmetic, Truth, and Paradoxes (Suanshu, zhen yu beilun 算术、真与悖论 (2017)). He developed a new truth schema-a relativized T-schema-the procedure of which is to expand Tarski's T-schema (' A' is true if and only if A) onto a relational framework. Or, in other words, speaking about arbitrary possible worlds u and v within the same framework, if u is accessible to v, then it is possible to establish the truth of A in u, if and only if A can be established in v. By virtue of this new kind of T-schema, Xiong was able to obtain a series of new results relating to the problem of liar-type paradoxes, which were for the most part published in important international A&HCI journals.

The Introduction of Informal Logic and Critical Thinking
Informal logic and critical thinking, two mutually highly overlapping concepts, were introduced to China in the 1990s. As the current editors-in-chief of the journal Informal Logic, Ralph Johnson and Anthony Blair, pointed out: informal logic is "a branch of logic whose task is to develop non-formal standards, criteria, procedures for the analysis, interpretation, evaluation, criticism and construction of argumentation" ( Johnson and Blair 1977, 147). According to my own research, "critical thinking" has got the following four important meanings: a reformist movement in education which originated in the United States and grew to popularity in Europe; it is an intellectual trait, orientation, and habit which must be possessed by a qualified citizen and an innovative talent in today's society; a string of reflective capacities, methods and strategies which must be adopted for making rational decisions about what we should believe or how we should act; a curriculum which aims at fostering the disposition, habit and ability of critical thinking (Chen 2017, 22).
After the year 2000, specialized treatises and textbooks on informal logic, and especially English works on critical thinking, underwent large-scale translation into Chinese. Some of these books were even translated more than once. In parallel to the translated works, Chinese scholars also published many introductory articles on informal logic and critical thinking, and subsequently some textbooks on the same subjects.  (2013)) he provides a systematic introduction to as well as independent research on argumentation schemes. Last but not least, in the last few decades, Xiong Minghui 熊明辉, Xie Yun 谢耘 and other Chinese researchers have managed to publish articles on informal logic, critical thinking and theory of discourse in leading international SSCI and A&HCI journals.

Transformations in Research on Legal Logic
Chinese studies on legal logic started in the 1980s, when the first set of related textbooks were published in China. At this early stage, however, the label "legal logic" (falü luoji 法律逻辑) described nothing new except adding examples of the principles of traditional logic from law and judicial practice. It was only after the year 2000 that a few Western works on legal inference and proof were translated into Chinese, and that a certain group of Chinese legal scientists started taking part in research on legal logic. Subsequently, using different kinds of resources or instruments-such as traditional formal logic, mathematical logic, informal logic, critical thinking, discourse theory, theory of legal inference and proof, legal science and legal philosophy-Chinese scholars started researching logical problems of law, judicial investigation and judicial trials and so on, and in turn developed an independent theory of legal logic. In the words of Lei Lei 雷磊: Legal logic has its application in legal epistemology, especially in theories about application of law. Legal logic represents an integral part of legal argumentation theory, it is applicable in the justification aspects but not discovery ones of law. The centre of its research resides in structural theory of legal norms and mode theory of legal argumentation. While the theory of norms studies the types of norms and the construction of normative systems, on the other hand, the theory of legal argumentation focuses on the elementary modes of legal debates. These, however, only constitute the object theories of legal logic, while the latter still requires a form of metatheory, which concerns with three main problems: Are norms the object of logical research? Is there any need for a special kind of logic about norms? Would this kind of logic abut norms be equipped with special logical laws? Furthermore, legal logic is faced with the limitations from two aspects, namely whether it recognizes law as a science, as well as the possibility that legal logic itself might implicitly contain limitations of its domain or its perspective. Hence, legal logic must take legalization (falühua 法律化) and formalization as the two main directions in the future. (Lei 2017, 188)

Chinese Logicians Start Entering the International Academic Arena
In the period between the 1950s and 1980s, the Chinese circle of logicians were in a state of almost complete isolation from the West, as a consequence of which there was a general lack of understanding of the situation in the field of logic outside China. At the same time, only an extremely small number of Chinese logicians managed to publish their research results in European and American logical, mathematical or philosophical journals. Due to the last four decades of reforms and opening up to the world, the state of Chinese logic has undergone a radical change compared to its state prior to 1978. At present, Chinese logicians are having substantial contacts with their international colleagues, at the same time many scholars have gained at least a year's experience of visiting or studying abroad, while some of them even earned their PhD degrees from foreign universities. Moreover, many Chinese logicians can now take part in or even preside over international academic conferences or workshops, and publish their articles in SCI, SSCI and A&HCI journals specialized in logic and philosophy, and or their monographs with English publishing houses.

Conclusion: Experiences and Lessons
Looking back at the past seven decades, we can feel quite a few regrets. Although, sharing its path with our republic, Chinese academic logic has walked a winding road, gaining an incredibly complex set of experiences, but it has still been able to embrace its ideals and, under the burden of its long-term mission, demonstrated unyielding initiative and tenaciousness. Due to such long-term efforts, Chinese academic logic was ultimately able to overcome its obstacles and thread down its great path forward, forging ahead towards development and prosperity. After careful reflection on past experience, I can provide at least four lessons which ought to serve as guidance for the future development of Chinese logic, or put more broadly, Chinese academics: 1. Let politics and academia each manage their appointed domains, thereby truly respecting and sustaining academic freedom In the three decades between 1949 and 1979, the main reason for the comparatively slow development of Chinese logic resided in the meddling of political powers. In the ROC period, owing to the efforts of Jin Yuelin and others, the newly emerging discipline of mathematical logic already reached a certain level of dissemination in China, having also educated a generation of new talent. In this period, some young scholars who earned their doctorates at European and American universities also had the opportunity to lead Chinese logic to the frontiers of modern science. Then, after the Revolution, and due to the intertwining of many different factors, the PRC regarded the Soviet Union as its "big brother", and engaged in unconditional learning from and emulation of the Soviets in all aspects and levels, to the degree that even logic as a completely non-ideological science was not exempt from this wholescale Sovietization. Thus, because in the Soviet Union mathematical logic was subjected to a long period of criticism and rejection, China also followed suit, criticizing and rejecting it as well, which ultimately resulted in a great delay in the development of mathematical logic in China. In addition to this, under the influence of Soviet ideology even traditional formal logic became equated with idealism and metaphysics (in contrast to dialectics), with the intention to eliminate its theoretical foothold. Fortunately, it was also due to political intervention that, under Mao Zedong's guidance, the great debates on logic happened in the 1950s and 1960s. These debates caused formal logic to regain its legitimacy and enabled its survival. Similarly, it was also Mao's support which led to two major waves of popularization of logic in China. As such, it is indeed the case that both the success and failures of logic in China were both due to the same cause.
In reality, the fundamental principles of dealing with the relationship between academia and politics ought to be let academia be taken care of by the academics and politics by politicians, they must not arbitrarily overstep their boundaries, and this will give rise to the peaceful coexistence of both sides. The criterion for clear partition of their territories is the national constitution: scholars are also citizens, and thus are obliged to abide by the constitution, while opinions against the constitution ought to be subjected to censorship and acts against the constitution to legal sanction. But, on the other hand, for any opinion and action, as long as it does not violate the constitution and its stipulated civil rights and stays within the category of speech, it belongs to the scope of civil liberties and academic freedom, into which no authority has the right to interfere. Even a poor person with his simple and poor abode has the courage to announce: The wind can enter, the rain can enter, but the king of the realm cannot. Our historical experiences have repeatedly made clear that respecting, protecting and supporting academic freedom is the fundamental precondition for preventing errors, discovering truth, and creating academic prosperity.
2. Science cannot advance in isolation from the international academic community; it needs to warmly embrace the community and, at the same time, insist on independent thinking Academia is essentially a public undertaking, the commonality of which can be conveyed with one word: sharing. First of all, through engaging in sharing their works with other members of academic community, a scholar is therefore able to get challenged, gain enlightenment, carry out consultations with their colleagues, and thereby enliven their own thought. Only by being able to stand on the shoulders of giants can a scholar gain a broader perspective and attain more outstanding ideas. Secondly, by sharing their own research results with other scholars, and thereupon receiving the feedback, criticism or challenges, a scholar can advance, deepen and develop their own theories or viewpoints, or inspire other members of the academic community to do the same. The smaller an academic community is, the greater the probability that it will get enshrouded in kind of bias. In contrast, the greater the community, the smaller the chance that it will be controlled by such bias. Again, a scholar only qualifies as an independent member of the academic community if they arrive at their own distinct viewpoints about a certain problem by means of independent reflection. Such a scholar also learns from and exchanges their views with other members of the community, and in that way also makes their own contribution to that community. If a scholar abandons independent thinking and conforms to the views of the majority, having no independent views or theories of their own, this will lead to the following outcome: if other people are between 1 and 9, such scholar will amount only to 0, having no special value of their own, but instead, through attaching themselves to the rears of the others, he highlights the significance and value of other scholars. The process of Chinese academic logic in the last seven decades serves as yet another example to corroborate all this. When Chinese logic was isolated from the rest of the world, its conditions was appropriately bad, while, on the other hand, when the country opened its doors and Chinese logic was able to embrace the world beyond, its potential also came to life, enabling it to attain development and prosperity. In the years to come, we must always remember this valuable lesson.
3. The promulgation of the "let a hundred flowers bloom and a hundred schools of thought contend" policy enabled different academic views to attain improvement and advancement through mutual collision An immense advantage of the Hundred Flowers campaign was to offer other possibilities, revealing alternative prospects, which had a corrective function for already existing ideas and learning. However, it seems that in the end only one branch was able to thrive, one single flower could bloom, and only one school of thought was allowed to dominate, thus what the campaign often produced was academic monotony, obstinate, bogged down or even characterized by complete academic statis. Even if, following Deng Xiaoping's reforms, a certain group of my Chinese peers once wanted to achieve the dominance of mathematical logic in the Chinese circle of logic, to the extent that they even wanted to freeze logic up to the level of mathematical logic, in particular to the level of the first-order logic, the reality soon turned the course of things into another direction. Stemming from several kinds of considerations and, above all, the practical demands of this era, Western logic ultimately treated the already extant mathematical logic as a mere method and instrument, while instead its main developmental focus shifted to advancing new deviant logics and expanded logics on the one hand, and developing new theories in philosophy of logic on the other. Moreover, this development even led to the advancement of informal logic and critical thinking as theoretical complements for the flaws and shortcomings of mathematical logic. Chinese logicians must always keep in mind this important lesson from the past, and always adhere to the policy of "let a hundred flowers bloom and a hundred schools of thought contend", letting different academic views adequately compete against each other, and thereby enabling their unceasing progress and improvement. 4. Gradually fostering academic self-confidence, to advance from follow-up learning to leading in innovation Because of China's stagnation and backwardness in the early modern era, in its contacts with the external world and especially with Western countries, we actively or passively played a role of a student or follower: while others were developing science and technology, we were merely learning from their science and technology; while others were doing research in philosophy, we were merely researching others' philosophy; while others had discovered or invented logic, we were merely studying and researching the logic from them. Although, in the past this stage of learning was necessary, it now needs not only to be surpassed but we now already possess the capacity to advance to the next stage: if others are researching X, we must study how the others research that X. Moreover, we should also join the others in their research of that X, and produce the Chinese people's own contributions to the research. Under the leadership of Ren Zhengfei 任正非, the Huawei company works exactly in this manner. It developed and expanded its own strengths, and therefore garnered great respect and met many challenges. Chinese logic ought to follow the same pattern as Huawei's, by gradually making the change from follow-up learning to leading. In the creative domain of logic, Chinese logicians must also make their own significant contributions, and we hope this day will arrive soon!