China was a powerful country in ancient times, which attracted many people from all over the world to congratulate it. At the same time, they learn advanced science and technology or ideology from us and spread it from this ancient land to all directions of the world. Our country is now strong again, but in the previous hundred years, our country fell behind the ever-changing world because of its closed door. China's mathematics in Song and Jin Dynasties was far ahead of other countries in the world at that time, even ahead of Europe 1000 years, but it was abandoned by Europe later. They walked in front of us because our country was closed to the outside world, and the ideological education science in medieval Europe was bound.

1. Medieval Europe was very dark and bloody. During the development of mathematics in China, Europe was in what we usually call the Middle Ages. At that time, the development of science education was strictly restricted, and the papal church did not allow those advanced ideas. Some of their basic science education was stagnant, but the ideas of the church prevailed in that land, so their mathematics at that time was far behind us until after the Renaissance. At that time, China was a feudal society, but some technologies were not suppressed, so we could lead Europe 1000 in Song and Jin mathematics.

As we said before, before the Qing Dynasty, the development of science and technology in China was very advanced in the world. It is precisely because of the closed door during the Qing Dynasty that we can't learn advanced ideas in time. After the Renaissance in Europe, their national strength and technology were higher than ours, but the rulers of our country at that time did not accept it. Therefore, China's mathematics has lost the opportunity of development, and it lags far behind Europe. Moreover, the rulers of the Qing dynasty were ethnic minorities, and they did not fully accept the culture of the Han nationality, and they have been enslaving their thoughts. Therefore, mathematical science has not developed.

In China one hundred and twenty years ago, we failed to seize the opportunity and keep ahead in science. Due to behind closed doors, we failed to catch up with the knowledge explosion era of19th century. At that time, knowledge exploded, with rapid change and speed. We fell behind for a while, so Song and Jin Mathematics, which was once ahead of Europe 1000 years, became a success. This is an opportunity for us not to catch up with the times, and the national conditions of China at that time did not support the development of mathematics.