1. Introduction

Confucianism is the national school of China and the core idea of traditional Chinese culture. Confucianism was founded by Confucius and was born out of the ritual and music traditions of the Zhou dynasty, with the core values of benevolence, sincerity, and filial piety. When Confucianism developed through the twists and turns of the Song Dynasty, Zhu Xi, the most accomplished Confucianist after Confucius, emerged. Zhu Xi devoted his life to the study of Confucianism, and he recognized the effectiveness of education for the popularization of ideas, so he could become an important figure in the transmission of Confucianism. Zhu Xi in scripture, history, literature, and even natural science exegesis, exegesis, annotation, and collation have made a large contribution. This paper will demonstrate the main thoughts of pre-Qin Confucianism, and how Zhu Xi reinterpreted Confucianism into an independent system of doctrine based on his inheritance of Confucianism. Through analysis, the significance of this paper is that Zhu Xi allowed Confucianism to rejuvenate in the context of the new era, based on which he thoroughly completed the construction of a new Confucian ideological system.

2. Briefly describe the ideological theories of pre-Qin Confucianism and Zhu Xi's philosophy

2.1. Pre-Qin Confucianism

After its birth, Confucianism did not become a system in its own right but was transformed into Confucianism by Confucius. Confucius was the one who transformed it into Confucianism because it was only from Confucius onwards that the ideology and theories of Confucianism were taken as a solid theoretical foundation, and this was the basis for the creation of the official Confucian school. The most noteworthy of Confucius' theories is his thesis on "ritual" and "benevolence". The former is an inheritance of the ancient tradition of poetry, calligraphy, ritual, and music, but it is not bound to the inherent form of the traditional ritual system and is modified. The latter is a theoretical adaptation of the ritual and music tradition, a new philosophy reflecting the spirit of the times of social change and the promotion of humanity. In Confucius' thought and theory, "ritual" is certainly important, but what is more important is "benevolence" [1]. “Rites" is only a form of discretionary gains and losses according to the needs of social reality, but this form can only gain value and meaning through the spirit of "benevolence" embedded in it.

During his life, Mencius devoted himself to studying Confucius and to promoting and bringing into play the doctrines and ideas of Confucius [2]. He made a significant contribution to the development of Confucianism and was therefore honored by later generations as a "sub-sage", second only to Confucius. Noteworthy among Mencius' theories of thought is the "people-oriented" doctrine and the "goodness of nature" doctrine. The former is the doctrine of "benevolent government", which is characterized by "people-centeredness". Mencius strongly advocated the idea of "people-centeredness" and believed that "the people are the most important, the community is second, and the ruler is the least." The latter is the doctrine of human nature based on the theory of "goodness of nature". Although Confucius made such remarks as "nature is similar, and habit is far away," he did not discuss the essence of human nature in detail. Mencius was the first scholar to explicitly put forward the theory of "goodness of nature", and he strongly advocated the theory that human nature is inherently good, starting the first Confucian theory of mind and nature [3]. Mencius' concept of mindfulness based on the theory of "goodness of nature" is a deepening of his understanding of the nature of human nature. Mencius completed the first turn in the history of Chinese philosophy from nature distorted by religion to man, which is undoubted of profound significance in the history of human intellectual and cultural development.

Xunzi's theory of human nature is completely different from Mencius', as Xunzi advocates the theory of "sexual evil" and believes that people are born with physical needs and material desires. Therefore, Xunzi attached great importance to the role of "rituals" and believed that "to make rituals to divide them, so that there are rich and poor, noble and lowly, enough to be able to be in each other's presence, is the essence of the world". Although Xunzi's so-called "rites" originated from Confucius, they have a broader scope than Confucius' theory of "rites". Xunzi believed that only by giving full play to the subject's motivation could a man continuously promote his progress and development. Xunzi's high recognition of the value of human beings fully demonstrates the enterprising spirit of his theory. Xunzi made significant contributions to the teaching of Confucian classics, and he emphasized the importance of studying Confucian classics at the theoretical level. Without Xunzi's inheritance and innovation of Confucianism, the rise of Han Confucian scripture would have been difficult to imagine. Generally speaking, the Confucianism of Confucius and Mencius focused on the theory of "goodness of nature" as the philosophical basis for the study of Confucianism, while the Confucianism of Xunzi focused on the theory of "evil of nature" as the philosophical basis for the development of Confucianism.

2.2. Zhu Xi's philosophy

Zhu Xi was a master of ancient Chinese philosophical thought, and his philosophy represents the highest level of development of Confucianism [4]. Zhu Xi combined the Analects of Confucius with Mencius and the two books of the Book of Rites, the University and the Middle Mean, into a new book called the Four Books. After the Song Dynasty, the social status of the Four Books gradually surpassed that of the traditional Confucian Five Classics. Zhu Xi inherited and carried forward the ideological theory of "The Great Learning", which is "to be materialistic, to be knowledgeable, to be sincere, to be righteous, to cultivate one's self, to be a family, to rule the country, and to level the world", and became the way for later Confucian scholars to know the system of science. Zhu Xi is one of the most erudite scholars in Chinese history after Confucius. To learn Confucian culture systematically, we must first understand Zhu Xi and his theory of philosophy.

Zhu Xi's philosophy represents the highest achievement in the development of Confucianism. In Zhu Xi's philosophical system, the most basic categories are reason and qi [5]. He believes that the generation of any specific thing between heaven and earth has a reason, but also has qi. The reason is the basis or origin of the creation of a thing, which is "the essence of living things". Qi is the material for the creation of a thing and is the "tool of living creatures". This "biological essence" is the invisible essence, with no image to follow, Zhu Xi called it the "metaphysical" way. Qi is the specific materials and substances that makeup things, it is the image to follow, and Zhu Xi called it the "metaphysical" tool. Reason and qi in the relationship are symbiotic coexistence, mutual inseparability, and inseparable. Zhu Xi combined the two individual philosophical categories of reason and qi, and based on the theory of reason and qi, he dismantled and constructed the Confucian theory of the goodness of nature, arguing that people should be subordinated to heavenly reason using the knowledge of things. At the same time, Zhu Xi provided a solid theoretical basis for the maintenance of the entire feudal system and value system.

3. Zhu Xi's succession and development of Confucianism

In the history of the development of Confucianism in China, Zhu Xi is a key figure, because, in the process of the inheritance and development of Confucian culture, Zhu Xi alone took on the important role of inheriting the first and initiating the next. As for the first part, Zhu Xi organized and analyzed the old Confucian ideas one by one and then dismantled them, and generated the later official philosophy of Zhu Xi, which was classified as the authentic Confucianism in the Ming and Qing dynasties. As for the role of enlightenment, Zhu Xi provided a new face to the Confucian cultural system. In terms of Confucian culture transmission, Zhu Xi inherited some of Confucius' thoughts and theories, and he promoted Confucianism to an unprecedented extent, an achievement unmatched by other sages. In the sense of the development of Confucianism, Zhu Xi is probably the only person in history who can be compared with Confucius. In the history of Chinese Confucianism, the role and influence of Zhu Xi's philosophy are second only to that of Confucius. Zhu Xi also placed great importance on the transmission of Confucian education, and his work The Collected Commentaries on the Four Books was set as the subject program for testing scholars [6], which led to a more extensive and profound study of Confucianism after the Song Dynasty than during the two Han dynasties.

In the Confucian classic "The Meaning of Nature", it is said that "Heaven's command is the meaning of nature". Confucianism believes that human nature comes from the mandate of heaven, while Zhu Xi proposes that the mandate of heaven is the natural principle of heaven and that human beings are born according to the principle of heaven and therefore have this human nature. In Zhu Xi's theory, "reason" is called the innate "nature" of human beings, that is, "the nature of nature", which is the basis of science shaped by Zhu Xi after inheriting part of Confucianism from Confucius and Mencius. But Zhu Xi did not just stop at restating the views of his predecessors, he had a different analysis of the relationship between sex, reason, and qi, and put forward a unique view. He believes that human nature is the reason for heaven and earth’s endowing to man, so the reason accepted by man becomes nature. Although man is the spirit of heaven and earth, with all things in the essence of the same point. Therefore, Zhu Xi introduced the concept of "qi", that the human form is composed of "qi", people in the feelings and desires of the drive can not be free, subject to the nature of "qi" that is the "nature of qi". Thus, Zhu Xi formally stated his view that human beings are not born with "goodness" because their "nature of qi" is different from that of the sages who possess "natural nature" [7]. From the opposition between the "nature of nature" and the "nature of temperament", it can be seen that Zhu Xi inherited part of the traditional Confucian theory of sexual goodness and then made a fundamental development, expounding a new understanding in line with the development trend of society.

Zhu Xi's greatest contribution to Confucianism is in the transmission and development of education. He organized the classical Confucian writings, such as the Analects, into reading materials for readers, and proposed viable methods for teaching these basic materials. In addition to improving the teaching materials, he also made a great contribution to the education of the people [8]. He taught children how to read and write, made people understand manners, and spread Confucianism to the people through many means of education. However, Zhu Xi did not simply inherit the Confucian philosophy from Confucius but developed and adapted it to the times. Confucius used the Six Arts to teach people, and the Six Classics were the main teaching materials, and the basic principle of education was that action was more important than knowledge. Zhu Zi, on the other hand, taught people with the Four Books, and from the Four Books to the Six Scriptures, the basic principle of education is that knowledge and action follow each other, and knowledge and erudition are important. In the concept of education, Zhu Xi placed the Six Classics after the Four Books, asking students to read the Four Books first and then the Six Classics, thus making the Confucian theory of Confucius and Mencius still remembered by students in the context of the new era. In short, Zhu Xi reconstructed the ideological theory of pre-Qin Confucianism, not only reconstructing the theoretical system of Confucianism but also constructing a cognitive theory and cognitive method that could stand the test of time.

Having briefly analyzed Zhu Xi's contribution to Confucianism in the area of education, we will next examine the issue of the relationship between heaven and man, which is important in Confucianism. Confucius believed that heaven was not a single concept, but a unity made up of disorderly contradictions. Confucius' focus fell more on the relationship between heaven and man, and he advocated that man should exert his subjective initiative and use his efforts to achieve the unity of heaven and man. Mencius developed along the lines of Confucius and proposed to explain "benevolence" by "heart", emphasizing inner cultivation to achieve the cultivation of an ideal personality, explaining the social history and interpersonal relationships from the heart and nature of man, and proposing the principle of "to be mindful, to know nature, and to know heaven". He explained the social history and human relations from the perspective of the human mind and nature and proposed the idea of "to be mindful, to know nature, and to know heaven", which is the harmony of heaven and man. Following the line of thought of Confucius and Mencius, Xunzi developed the idea that "ritual" could be used to explain "benevolence", and he focused on the humanistic thought of Confucius. In addition, Xunzi emphasized the role of "force" in the relationship between human beings and nature, and proposed the brilliant ideas of "the division of tomorrow into human beings" and "the use of the mandate of heaven". The path of "the separation of heaven and man". Xunzi's thought, in terms of development and change, is a great step forward from Mencius' thought and has reached the highest level of development of understanding in the pre-Qin Dynasty.

In the Han Dynasty, Dong Zhongshu inherited the line of thought of Confucius and Mencius on the "unity of heaven and man", and took advantage of Xunzi's flaw of considering the function of the natural heaven as "unknown things" to put forward the "induction of heaven and man". The doctrine of "Heavenly Induction" was proposed. Although he cited a large number of materials on yin and yang, the five elements, and natural science, he did not apply these materials from a scientific point of view, but used subjective analogies and fictional appendages to establish the ideological system of "induction of heaven and man". Although this idea of Dong Zhongshu served the feudal centralization of the landowning class in the ascendant period politically and had certain social value and significance of the times, from the perspective of the development of history as a whole, he did not advance people's understanding to improve their understanding of the objective world, but vigorously promoted obscurantism and fideism.

On this issue of the relationship between heaven and man, Zhu Xi still adheres to the line of thought of "the unity of heaven and man" since Confucius and Mencius. However, his idea of "the unity of heaven and man" is not expressed simply and directly like Confucius and Mencius, but is presented in the discursive philosophy of science. Zhu Xi inherited the achievements of cognitive development since Confucius and the continuous development of natural science, and made new changes and developments to the pre-Qin Confucian idea of "the unity of heaven and man".

4. Zhu Xi's Transformation and Innovation of Confucianism

In the history of Confucianism, the Song and Ming philosophies have traditionally been regarded as "Neo-Confucianism. By "Neo-Confucianism," I mean that it is a development of Confucianism represented by Confucius. In other words, "Neo-Confucianism" promoted the development of Confucianism under the new historical conditions of the late feudal society, and made certain modifications and innovations to the ideological theories of pre-Qin Confucianism. Zhu Xi was the master of the two Song dynasties, and he thoughtfully expressed his structure and reorganization of Confucianism. On the whole, Song dynasty philosophy has accomplished various "inward" transformations of pre-Qin Confucianism, such as the shift from focusing on external merit to focusing on internal aspirations, or the shift from external scripture to internal benevolence [9]. In his classical interpretation, Zhu Xi, the great master of Song dynasty philosophy, vividly embodied the transformation of Confucianism from "political practice" to "inner body of evidence".

After the collapse of the Han dynasty, the Five Classics, as the ideology of the dynasty, gradually lost the support of political power and the centripetal force of the scholars, and along with the liberation of individuality in the Wei and Jin dynasties and the baptism of doubt in the Tang dynasty, the "political attempts" of traditional Confucianism were further belittled [10]. Therefore, traditional Confucianism and social and political practice needed to be closely integrated to face the strong impact of Buddhist and Taoist doctrines [11].

As a major figure in the field of science, Chu Hsi developed a new interpretation of Mencius in his consideration of the "respect for Mencius" and "doubts about Mencius" in the Song Dynasty. He creatively brought into play the discourse on the practice of mind and will in the text of Mencius, deeply explored the profound connotation of humanistic ethical doctrine in it, and opened up a line of interpretation of the classics employing mindfulness. He uses the structure of "reason and qi" to highlight the unifying effect of "reason" on the "way of heaven" and "human nature", effectively weakening the scripture's focus on the "way of heaven" [12]. He effectively weakened the utilitarianism of the sutra. The rationalists spent a great deal of effort to transform some of the theories of traditional Confucianism so that Confucianism could develop partially free from the constraints of external political forces on the subject's behavior and thus have a foundation to confront the doctrines of Buddhism and Taoism.

In the face of the two trends of "respecting Mencius" and "doubting Mencius" in the Song Dynasty, Zhu Xi maintained his cool and analytical mind. Through his interpretation of the original text of Mencius, he answered many of the world's questions about Mencius' thoughts in a reflective manner. From Zhu Xi's commentary, we can see that his interpretation of Mencius has changed the direction of the traditional argument of "politics" and entered into the discussion of "morality". Zhu Xi wanted to carry forward Mencius' heart and soul and to take up the mission of continuing the Confucian tradition of morality for thousands of years. While he affirmed the significance of Mencius' doctrine, he also gave his interpretation of the basis for transforming Confucian and Mencian orthodoxy to develop Confucianism as his mission. In a certain sense, this was also Zhu Xi's response to the social anomaly of the prevailing Buddhist and Lao doctrines. He hoped that by interpreting Mencius, he could revitalize Confucianism and build up a complete moral value of Confucianism in the doctrine of doctrine to reject the doctrine of Buddhism and Lao, and thus inherit the doctrine of thousands of years of sages.

There is no doubt that Zhu Xi was the mastermind of the era of Confucian spiritual revival. His interpretation of Mencius, making full use of the ideas of science, was purposeful, elevating the logic of the argument of necessity in ethical praxis as a way to transform the traditional Confucian doctrine. In his interpretation, one can see the imprint of the fusion of Confucianism's teleology, Buddhism's sexology, and Taoism's heavenly pathology, which happen to be the three important theoretical foundations for the formation of Song dynasty doctrine. The theory draws on the constructive experience of the metaphysics of Buddhism and Taoism to establish its ontological theoretical system, which in essence enriches the "humanistic" connotation inherent in Confucianism.

Through his interpretation of the text of Mencius, Zhu Xi has well justified that the human subject's mind can pass through "heavenly reason" and "natural reason". It was along this line of thought that Zhu Xi used the Four Books, represented by Mencius, to gradually replace the Five Classics as the new core text of the Confucian ideological system, and since then the traditional Confucian system of "king's words" has been formally transformed into a system of "holy words". The RI also completed the perfect transformation of Confucianism from the traditional institutionalized utilitarianism of kingship and the authoritarianism of scripture history to the humanistic ethical system of Confucianism and Mencius. This transformation was a natural result of the historical and cultural reasons of the society of the time and of the moderate development of the Confucian gentleman's ability to reason. From then on, the Confucian ethical theory of mind and will was completely separated from the theory of political practice, which was the ideological system of the emperor, and Confucian scholars were clear that they could not become subjects before becoming benevolent through the path of Confucianism. The purpose of the Confucian scholarship is to "learn from below and attain above" by reading the books of Confucius. This undoubtedly broadened the development of Confucianism, and in its action, it distinguished between the political and ethical beliefs of scholars and gentlemen, and a new impetus for the development of Confucianism was born under Zhu Xi's transformation.

5. Conclusion

In summary, although Zhu Xi's philosophy of thought at that time and for a long time after, for people's philosophical enlightenment and self-improvement, and even the cognitive construction of society and historical development, have extremely important ideological significance, now seems to be a rigid philosophical system, which is Zhu Xi's philosophy does not adapt to the historical limitations of modern culture. Zhu Xi's philosophy has been integrated into the cultural tradition of Chinese thought and has made positive theoretical contributions to China's socio-historical concept of human decency, moral integrity, and collective responsibility, as well as to the personal conduct of self-restraint, self-motivation, and goodwill. It is because of Zhu Xi that Confucianism has continued to flourish and become more deeply rooted in people's minds. Through the dynastic changes, the Confucianism of Confucius and Mencius did not cause any obstacles to the development of inheritance. The vitality of pre-Qin Confucianism lies in its close connection with the times, and it is precise because Zhu Xi understood this that he wanted to restore its vitality in the society of the time. Therefore, Zhu Xi made a great contribution to the development of Confucianism and Mencianism by integrating the great achievements of science. Culture is a long and continuous stream, and it is the rule that there is succession before and continuation after. By exploring the origins of Confucianism, we can realize the philosophy that culture is born out of the needs of the times, but must serve the times. To sum up, Zhu Xi's structural reconstruction of Confucianism is a colorful and important chapter in Chinese history, but to continue to carry forward the charm of Zhu Xi's doctrine it is necessary for later scholars to discover different interpretations of existing theories from different perspectives and to inject a stronger impetus into the development of Chinese culture.