In the history of human thought, the category of justice occupies a very important position. In ancient Greece, especially in Socrates and Plato, justice was already the most important virtue. Plato thought in the Republic: "Justice can endow other virtues belonging to the national legal system-temperance, courage, wisdom, and the power to exist and continue to exist under this general view." Aristotle believes that "justice is the most important of virtues, which is more brilliant than the stars" and "justice is not a part of virtue, but the whole of virtue". Humans have deeply realized in their own lives that "one thing is more important to human welfare than anything else, and that is justice". However, thinkers have different answers to what is justice. Socrates believes that "justice is the best way to act". Plato believes that "justice should be the moral principle of human virtue, which is embodied in performing their duties, keeping order and getting their place". Aristotle believed that "justice is law-abiding and equality". Epicurus believed that "justice is a social contract of mutual happiness. Cicero believes that justice is the human spiritual orientation that enables everyone to get what they deserve. " The ancient Roman jurist Urbian believed that "justice is the eternal will to make everyone get what they deserve". Augustine believes that God's justice is the standard and foundation of all existing things. Hobbes believes that justice means keeping promises, and its purpose is to end the "natural state that man is a wolf to man". Spinoza believes that justice is freedom of thought and law-abiding action. Hume believes that justice is an artificial virtue of respecting property. Rousseau believes that justice is the people's sovereignty, social contract and a kind of public will. Kant believes that justice is a kind will. Sidivik believes that justice is one thing and should be treated equally. Nietzsche believes that justice is the will of the strong. Dewey believes that justice is a tool to deal with moral conditions. Kelsen believes that justice is based on "the value judgment made by subjective emotional factors". According to Pound, justice is a straight road. ...... For centuries, philosophers, ethicists and jurists have put forward various views on justice and adopted many ways of thinking to solve social justice problems. As Bodenheimer, an American legal philosopher, said when examining the viewpoint of justice in human history, "Justice has an ever-changing face, which can take different forms at any time and has a very different look. When we carefully observe this face and try to uncover its hidden The Secret Behind, we are often deeply puzzled. In the contemporary west, since Rawls, an American scholar, published his masterpiece "A Theory of Justice" in 197 1, the issue of justice has become a common concern and heated discussion among various social sciences, especially political philosophers, sociologists and even economists. However, what is justice? "Still not the same. Utilitarians believe that justice is utility, Rawls says justice is fairness, Nozick thinks justice is individual right, and Mai Gentile says justice is virtue. Utilitarianism: Justice is utility. Utilitarianism and liberalism represent the two poles of contemporary justice theory. The former emphasizes the maximization of social welfare as a whole, while the latter emphasizes the priority of individual freedom rights. Since 1970s, liberalism has been dominant in the west, but utilitarianism has not disappeared. Utilitarianism came into being at the end of 18 and the beginning of 19. At that time, "interests were promoted to human rulers" and "all relations between people (individuals or countries) formed commercial relations, or in other words, property and things became the rulers of the world". Based on the theory of happiness and the principle of individual interests, utilitarianism neither agrees with the theory of natural rights based on the theory of individual rights nor with the theory of the origin of individual rights, but insists on "the greatest happiness of the greatest number of people" as the primary and fundamental principle, and holds that the symbol to measure the best regime and political system is whether it can obtain the greatest welfare and ensure the harmony of interests. As Mill said, "Happiness is the only purpose of human behavior, and enhancing happiness is the standard to judge all human behaviors". The first and highest principle of utilitarianism is the greatest happiness of most people, while the principle of justice is an important principle derived from the first and highest principle of "the greatest happiness of most people" through people's sense of security and compassion. The core content and fundamental foundation of justice is utilitarianism. Without utilitarianism, justice cannot be discussed. Muller said: "It is always obvious that all just cases are convenient cases; "The difference is that a just thing will cause a special feeling, and interests will not cause this feeling." Like classical economics at that time, the so-called greatest goodness of utilitarianism refers to the greatest income, and they did not consider the unfairness of distribution. According to the justice standard of utilitarianism, the social distribution that maximizes individual utility in society is just distribution. Among contemporary thinkers, British philosopher Richard Hale and American economist John Hasani are both active advocates of utilitarianism. According to Halsani's theory, people's natural choice after veil of ignorance is to maximize their expected income. Because everyone doesn't know the future, he treats every position in society equally and thinks that the probability of getting every position is equal. Therefore, his goal is to maximize the expected utility of all possible positions, that is, the average utility of all positions (that is, all people) in society: in the case of a fixed number of people, this is equivalent to maximizing the sum of the utilities of all members of society. Utilitarianism is a rational choice for people to get out of ignorance. Utilitarian justice theory establishes the principle of justice around social interests and regards the welfare of the greatest number of people as the standard of justice. This is consistent with Pareto optimal principle. In a certain sense, adhering to the principle of the greatest happiness of the greatest number of people is the fundamental guarantee for the long-term prosperity and stability of society. This is because interest is the value goal that people pursue. In a sense, it is an indispensable factor in people's real life to insist that interest is inseparable from people. Mankind's pursuit of justice is destined to be related to the development and perfection of human interest relations. All the value goals that people pursue (justice, fairness, freedom, democracy and equality) are related to people's interests. In this sense, interest or utility is indeed the primary value of justice. Of course, as a theory of social justice, utilitarianism has many loopholes. As Mill himself said, "One of the biggest obstacles that make it difficult for people to accept the theory of taking function or happiness as the standard of right and wrong is the concept of justice." One of the dilemmas of utilitarianism is to ignore people's basic rights. Although utilitarianism pays more attention to the poor when maximizing the total social welfare due to the law of diminishing marginal utility of income, it often ignores the interests of the lower class when allocating social production capacity. What is even more embarrassing for utilitarians is that according to the principle of utilitarianism, slavery is a system that conforms to social justice. Because Robert vogel, the Nobel laureate in economics, told us that slavery in the southern United States is very effective as an economic system. Utilitarianism's neglect of people's basic rights is the motivation for American philosopher john rawls to seek a new theory of justice. Rawls: Justice is fairness. In A Theory of Justice, Rawls tried to establish a new ethical system based on social contract. Almost at the same time as Hasani, he constructed his own ethical system on the analytical concepts of original state, veil of ignorance and rational choice. Unlike Halsani, Rawls emphasizes that his theory is the standardization of the past social contract theory (such as Kant and Rousseau's). When determining the personal selection mechanism after veil of ignorance, he adopted a different principle from Halsani, that is, the maximum and minimum principle. Rawls defined his controversial view as "justice as fairness". In Rawls' view, the rights of freedom and equality, the opportunity of fair competition and property are basic human rights, which are inviolable and inalienable: "Justice denies that it is justified to deprive others of their freedom for some people to share greater interests, and does not admit that the greater interests enjoyed by many people can have room to compensate for the sacrifices imposed on a few people." Through reasonable institutional arrangements, "all societies are basically good-freedom and opportunity, income and wealth, and self-esteem." However, because people's living conditions are limited and influenced by the political system and general economic and social conditions, they will suffer from initial inequality, and the initial differences and inequalities will bring profound and lasting further differences and inequalities. Therefore, Rawls set the original state of "veil of ignorance+mutual indifference" according to the method of abstract social contract theory. After the veil of ignorance, everyone can't determine his position in society. "Free people who have no power relationship with each other may recognize each other's principles" and reach an agreement on the basic structure of society and make choices. After the veil of ignorance, he extended two principles of justice: "the first principle: everyone should have equal rights and enjoy a similar freedom system compatible with the most extensive basic freedom system owned by others." The second principle: social and economic inequality should be arranged reasonably to meet everyone's interests; And it is open to everyone according to identity and position. " The first principle is the principle of equality and freedom; The second principle includes the principle of equal opportunity and the principle of difference. Rawls believes that the two principles of justice are arranged in dictionary order, that is, the first principle takes precedence over the second principle, and the fairness principle of the second principle takes precedence over the difference principle. Only when the former principle is fully satisfied can the latter principle be considered. Rawls' theory of justice is a great return to transcendental liberalism, which endows liberalism with new foundation and vitality and forms a new school of liberalism after Hayek's theory of spontaneous order. His criticism of utilitarianism is not only a response to the radical left-wing ideological trend in the 1960s, but also a summary and arrangement of them. Rawls pays attention to the social macro-structure (social system), the social macro-mechanism of rights distribution and the fair distribution of social power, regards the protection of the weak, the poor and the losers as the basic first condition of a just society, and emphasizes that people should be treated as equal people. This theoretical conception with equality as the core has considerable theoretical and practical value in contemporary society, which marks the change of the theme of western political philosophy from "freedom" to "equality" and is of great significance. Rawls' theory that justice is fairness has aroused widespread concern in the western world. It has not only won widespread praise for Rawls, but also been widely challenged by the theoretical circle: "Rawls' theory overemphasizes the inequality of talent and pays too little attention to people's own choices ... The overall color is sympathy for the weak, not a reward for the strong. "Obviously, this is unacceptable to many people. Nozick is one of the famous representatives.