of social theory is still very low. Biology has achieved rich results and formed a set of methods and paradigms. The discovery of biological gene brought about a revolution. It has freed people from  complex traits of plant and animal. In a genetic project, people can use some simple methods to create miracles. In the past, sociologists can only envy these successes. Now the similarities between cultural genes and biological genes make infinite imagination. People can promote the development of social sciences, even to revolution.

Baudrillard did not compare symbols with biological genes, but his theory of simulacrum belongs to the theory of cultural gene. Karl Popper made this comparison, but he did not directly point out the relationship between the third world and biological genes. Susan Blackmore's meme theory has raised the relationship between cultural genes and biological genes to unprecedented heights, but there are also obvious flaws.

Popper, Baudrillard, and Blackmore all discovered the role of symbols in social development, but they did not learn from each other. Because their understanding of the role of symbols and copying is not thorough enough, they cannot be consistent and research separately.

Popper's Theory of the Third World

The theory of the third world is a major research resulted in Popper's evolutionary epistemology. This theory puts forward some important ideas of the general evolutionary theory. Popper believes that the cultural background is relatively free from the creators. There is a third world, “the world of the objective contents of the thought, especially the scientific and poetic thought and of works of art”. The first world is “the world of physical objects or of physical states”, the second world is “the world of states of consciousness or of mental states, or perhaps of behavioural dispositions to act.”^[1]

Popper found the independence of knowledge expressed in words, which is different from other substances and  consciousness, and deserves special status. The meaning of Popper's “objective content of ideas” is not accurate. If it refers to the system of word and symbols, then some of his theory made sense.

Popper believes that the development of knowledge is very similar to the evolution of animals and plants. ^[2] We should understand that the objective content of the idea (the order of symbols in the textual which is constantly innovating) is essentially the product of the process of material getting complex and orderly after human beings originated, that is, part of the general evolutionary product.  Although Popper did not use the term “general evolution”, nor did he make it clear, he actually pointed out that the development of knowledge was general evolution and pointed out the specific way of general evolution. That is P1-TT-EE-P2, in which P1 and P2 represent problems, TT (the tentative theory) is the imaginative conjectural solution which we first reach