The unity of value is the core proposition demonstrated by Dworkin in his book Justice for hedgehogs. The basic viewpoint of this proposition is that ethical value and moral value are unified, and the unity of value is human dignity. While, it is very difficult to prove this proposition. Dworkin must face the challenge of two theories at first: one is the value skepticism theory; the other is the value pluralism theory. Among them, value skepticism, based on Hume's principle, denies the “objectivity and truth” of value. Value pluralism holds that different values are inevitably “conflicting” and “incommensurable”. In the face of such a theoretical dilemma, Dworkin, on the one hand, through the analysis of the independence of value, and points out that the “objectivity and truth” of value does not need external objective value entities (or “moral particles”) as a support, thus effectively responding to the questioning of value skepticism. On the other hand, he integrated the unity of different values through constructive interpretation and constructed a “web of values” with coherence and unity, thus successfully eliminating the challenge of value pluralism. Therefore, value skepticism and value pluralism do not pose a fatal threat to the unity of value. In other words, they do not hinder or deny the possibility of value unity. After clearing the theoretical barriers, Dworkin starts with ethics, bases on the two principles of dignity (self-respect and authenticity), and takes the responsibility system as the link, deduces the formation process and internal logic of the unity of values—form the ethical responsibility to individual moral responsibility, form individual moral responsibility to political obligation, and form political obligation to individual right. First of all, the logical starting point of the unified theory of value is ethical value. Specifically, it is a special ethical value—human dignity. In his views, human dignity consists of two basic principles: self-respect and authenticity. The former requires everyone to take his life seriously. The latter requires that each person has a special personal responsibility to determine what constitutes success in his own life. Secondly, according to Dworkin, these two principles of dignity do triple responsibility. First is the ethical responsibility, they provide guidance about what we should do in order to live well. The second is moral responsibility, each person's moral obligation to others. The third is political responsibility, the political obligation of the political community to every citizen under its jurisdiction. Finally, political obligations and civil rights are two sides of the same coin. The political obligations undertaken by a political community are actually the individual rights enjoyed by citizens against the political community. It mainly includes political rights, legal rights and human rights. Thus, various values such as ethics, morality, politics and law were successfully integrated by Dworkin, forming a tree-like structure of values: law is a branch of political morality, political morality is a branch of individual morality, and individual morality is a branch of ethical life. This is not only the internal logic of his unified theory of value, but also the formation process of his unified theory of value. It can be seen that Dworkin's demonstration of the unified theory of value is successful, that is, the unity of value is possible. The significance of Dworkin's unified theory of value is that he tries to put forward a new view of justice or a new standard for judging the legitimacy of government, which is obviously different from Rawls's theory of justice. He cautions that: first, the legitimacy of any government must be based on two fundamental principles of dignity; And it is the responsibility and obligation of any government to ensure that every citizen it governs lives well with dignity and happiness. Second, everyone must take seriously their own dignity, which is everyone's ethical responsibility, but also everyone's moral responsibility.