Because the world is chaotic, the government's control is weak, and there are few constraints and restrictions on ideology and culture, then cultural thoughts can develop greatly, and a number of masters have emerged. The most typical period is the Spring and Autumn Period and the Warring States Period, which is the most chaotic period and also a period of contention and academic brilliance. Others, such as the late Ming and early Qing Dynasties, the late Qing Dynasty and the Republic of China, are typical examples.

And as upstairs said, whenever there is a cultural trend of thought in history, it is in the period of social change, because in the period of social change, it must be the cultural people who feel the deepest. Social change is accompanied by cultural change and ideological change, just like the Renaissance in the west in history, and it is an inevitable product in a specific historical environment. The Renaissance in the West is indeed a phenomenon with the development of productive forces in the process of social change. So in the late Ming and early Qing dynasties, it was not these people who suddenly appeared, but they appeared in front of the historical stage in a specific historical period, appeared in front of us, and we saw them. Assuming that there were no Qing soldiers entering the customs and the establishment of the Qing Dynasty, there would still be thinkers like them, but they didn't have the opportunity to understand the pain caused by cultural changes. They must still be writing books where they don't pay attention to society and can't push the forefront of the historical stage. This is the same reason that the times make heroes. It's not that there were no heroes in a certain period, but that you couldn't stand out in that environment.