At the beginning of the 20th century, Sun Yat-sen summed up the historical lessons, absorbed the achievements of predecessors, followed the trend that various factions advocating anti-aggression and reform were close to each other, and carried out ideological innovation. He realized that if China wants to get rid of the colonial shadow and overcome poverty and weakness, it must change the fragmented situation, so that the strength of people of all classes and classes who are unwilling to perish will not be reduced because of internal friction. To solve the problem of social reorganization, China must have a banner of unity, that is, the Three People's Principles. Nationalism: Before the Revolution of 1911, the basic content of Sun Yat-sen's nationalism was to overthrow the Qing government headed by Manchu nobles by revolutionary means, and strive to avoid the fate of being "controlled" or "carved up" by imperialism and establish an independent nation-state. First of all, he absorbed the concept of nationality in modern western countries and discussed the origin, definition and essence of nationality. It is pointed out that the formation of a nation comes from five natural forces: blood, life, language, religion and custom, which link the formation of a nation with factors such as economy, culture and custom. Secondly, he demonstrated his nationalism with modern western political views. "Nationalism is the freedom of the country" is what Lincoln called "owned by the people". Third, draw lessons from the western modern national theory and put forward the idea of establishing a modern nation-state. It is pointed out that China should follow the example of the United States and integrate all ethnic groups in China into a Chinese nation. Democracy: Before the Revolution of 1911, the basic content of Sun Yat-sen's democracy was to overthrow the feudal monarchy by means of the national revolution, establish an equal, democratic and constitutional bourgeois republic, and implement political democratization. He explained the Three People's Principles with freedom, equality and fraternity, and thought that the national revolution was "the spirit of freedom, equality and fraternity of all people in a country". Freedom, equality and fraternity are the spiritual pillars of the Three People's Principles and the concrete embodiment of the civil rights thought. Only when all citizens have the concept of civil rights and are aware of their responsibilities can a real Republic of China be established. How can we develop civil rights? He believes that people's assembly concept and ability should be cultivated. For thousands of years, feudal rulers banned people's assembly and deprived people of their political rights, resulting in China people having no principles, organizations, habits and experience of assembly and becoming a "fragmented people". This national quality cannot meet the requirements of the times and must be changed. When he constructed the theory of civil rights and designed the national political system, he also absorbed Montesquieu's theory of separation of powers and checks and balances and prevention of autocracy. In the book "Preliminary Civil Rights", he provided detailed civil rights procedures, from the organization and principles of the assembly to every detail, telling people how to meet, speak and vote, how to be the chairman of the meeting, how to put forward proposals and so on. , and even lists various formats and samples. People's livelihood: Before the Revolution of 1911, the content of Sun Yat-sen's people's livelihood thought can be summarized as two points, namely, equal land ownership and developing modern economy. The land issue is the most important issue in the late feudal society of China, and all major social problems are related to it. Farmers are the main force of China's national democratic revolution. Without mobilizing farmers to participate in the struggle, there would be no strong national democratic movement. To mobilize farmers, it is necessary to overthrow the feudal land system and meet farmers' land requirements. Before the Revolution of 1911, Sun Yat-sen used the slogan of "equal land rights" to mobilize farmers to participate in the revolution, and really saw the importance of solving the problem of farmers' land for the success of the revolution. He also put forward the idea of "checking the land price and making a counter-offer to the people", focusing on solving the urban land problem after the development of industry and commerce. With regard to the development of modern economy, Sun Yat-sen put forward in 1894 that as long as "people make the best use of their talents, land and goods flow smoothly", China can become a rich and powerful country that "drives Europe to the top". After the Revolution of 1911, Sun Yat-sen put forward a plan to introduce foreign capital and technology on a large scale, carry out economic construction in an all-round way and realize the modernization of industry and agriculture. In Sun Yat-sen's Three People's Principles, nationality, civil rights and people's livelihood are no longer separated, but play a role as an organic whole: nationalism is the cultural background to realize civil rights and people's livelihood on the basis of * * * the same history and * * the same culture under the condition of weak modern economy and underdeveloped domestic economic ties; People's livelihood is the ideal to solve the disparity between the rich and the poor and make the people rich together, and it is the economic basis for the realization of national civil rights. Democracy conforms to the trend of modern history and creates the necessary democratic atmosphere and mass base for realizing the national economy and people's livelihood. The three are the premise and cause of each other, and they are internally and inseparably organized. Regarding the internal relationship among national character, civil rights and people's livelihood, Sun Yat-sen pointed out that the revolution he carried out was to solve the national revolution, political revolution and social revolution together. He said: "We overthrew the Manchu government, which was a national revolution in terms of expelling Manchu; From the side of subverting the monarchy, it is a political revolution, which is divided into two. " He also said: "The troubles in European and American societies have been lurking for decades. If they are discovered again today, they cannot be driven away. People who govern people's livelihood in China are the first to develop. Seeing that their harm has not yet sprouted, we can really take the political revolution and social revolution and fight it out in one battle. I still put Europe and America in my eyes, and I am behind. " He inspected the modernization of foreign countries, analyzed their experiences and lessons, and realized that even if a modern economic system and democratic politics were established, it would not be true modernization if the disparity between the rich and the poor was not solved. In order to avoid the disadvantages of Europe and America, Sun Yat-sen is determined to solve this problem once and for all, that is, "adopt the principle of people's livelihood and solve the problems of nationality and civil rights at the same time." The thought of the Three People's Principles will be completed. "From a strategic point of view, this" one-step "method does not conform to the principle of the revolutionary stage theory, but from a strategic point of view, it correctly points out the social organization mode of realizing modernization in an economically backward country like China. To study Sun Yat-sen's Three People's Principles, we should not only examine each part separately, but also grasp it from the overall perspective, so as to realize the great role of the Three People's Principles in gathering revolutionary forces, overthrowing the imperial system and establishing the Republic of China. Sun Yat-sen inherited the reasonable core of Taiping Heavenly Kingdom's thought of opposing national oppression, abandoned his narrow thought of national revenge to a certain extent, and combined it with anti-imperialist thought to form modern nationalism. His national thought is supported not only by various factions advocating anti-Qing, but also by various factions advocating anti-imperialism, and even attracts conservative forces advocating anti-imperialism and patriotism, which is more widely representative. He criticized the imperial thought, absorbed the essence of modern democratic thought, and got the support of a new generation of intellectuals. He put forward the anti-feudal land program, which satisfied the peasants and the bourgeoisie to varying degrees, and did not infringe the interests of the landlord class excessively because of his redemption policy; His idea of developing modern economy not only conforms to the ideal of the national bourgeoisie, but also does not violate the wishes of some landlords who advocate enriching Qiang Bing. In a word, starting from China's national conditions, Sun Yat-sen not only considered the primary goal of the revolution, but also took into account the main interests of various factions. He integrated the loose, tight and even conflicting ideas reflected by the interests of different classes and strata, coordinated them in the interaction of nationality, civil rights and people's livelihood, and scientifically expounded the strategic principles for winning the national democratic revolution. In the Three People's Principles, the ideas of nationality, civil rights and people's livelihood are no longer isolated from each other, but are interrelated, which provides effective communication channels for all classes and strata, enables all factions to coordinate their actions under the same goal, and greatly enhances the struggle strength of the Chinese nation as a whole. The Three People's Principles based on system theory is of great significance to the anti-imperialist and anti-feudal movement in China. Under this guidance, great changes have taken place in the revolutionary situation in China. First, the Three People's Principles contain the positive factors of all factions, making it an acceptable theoretical system for all reformers and unifying the revolutionary goals. Second, it has promoted the unity of all revolutionary factions, so that the struggle of advanced elements of all classes and strata is no longer dispersed, but has begun to gather under the banner of the Three People's Principles. Only two years after the Three People's Principles were put forward, the first unified coalition of bourgeois political parties was established in China, which freed China's anti-feudal struggle from its own situation and led it by organized forces. Third, it promoted the initial formation of the anti-imperialist and anti-feudal United front. According to statistics, not only bourgeois revolutionaries, bourgeois reformers, peasants, landlords, Communist party member, industrialists and businessmen, intellectuals, and even some honest officials and a considerable number of honest soldiers joined the League and its peripheral organizations. The classes and strata of its participants are extensive, which was not found in the previous reform and revolutionary movements. Fourth, it accelerated the disintegration of the feudal camp. During the Taiping Heavenly Kingdom, landlords from all over the country organized groups to suppress peasant uprisings crazily, and their activities played an important role in prolonging the life of the Qing Dynasty. However, in the Revolution of 1911, the attitude of Han landlords was quite different. Many people are waiting for neutrality, while the number of people who actively safeguard the rule of the Qing Dynasty is relatively reduced, and even a considerable number of people turn to the anti-Qing camp. Fifth, it accelerated the collapse of the Qing Dynasty and feudal autocracy. Only eight years after the Three People's Principles were put forward, the revolutionary forces led by the League overthrew the Qing Dynasty and ended the feudal autocratic rule that lasted for two thousand years, which showed its great impetus to historical progress.