From the Renaissance to the Enlightenment, western thought gradually formed two main tributaries, which were called European constructive rationality and British critical rationality respectively according to the geographical distribution of the birthplace and main thinkers. The former emphasizes the rational power of human beings and thinks that people can understand the world through rationality and use it as a tool to consciously transform the world (so-called "construction"), which tends to be known; The latter emphasizes the limitation of human cognitive ability, the role of experience in cognition and its defects, opposes the omnipotence of reason, advocates the protection of human basic freedom (so-called "criticism"), and tends to agnosticism and skepticism. Since the 20th century, the influence of constructive rationality has reached its peak in Europe, but the "fatal conceit" of human rationality caused by it has caused two disasters: extreme left and extreme right. Hayek started from economics and extended from the starting point of free market economy to political philosophy, psychology and cognitive science. He pointed out that the motive force of the development of human society lies in the spontaneous order that naturally appears in the continuous game between groups rather than the artificially designed order, that is, "history is the result of action rather than plan". The premise of the healthy growth of spontaneous order is individual freedom, and market economy is the most powerful guarantee of freedom. At the same time, he stressed that we should be wary of rational conceit and not let it become a threat to freedom. These are the ideological reasons for his persistent opposition to socialism and welfare society. Hayek's significance lies in that in the first half of the 20th century, when the conceit of human rationality reached its peak, the ideological circle generally turned left, and the welfare state, big government and Keynesianism prevailed, the British tradition of critical rationality continued, and the meaning and vision of classical liberalism were rediscovered and developed. At the same time, he tried to clarify the limitations of human cognitive and thinking ability and clarify the meaning of freedom through cognitive science and psychology.