Why is there a saying that "the Han dynasty is strong in Tang dynasty and Song gang is rich in dogs"?

We often say that "the Han Dynasty prospers the Tang Dynasty, and the Song Dynasty is rich and the dog is clear". Why would someone say that? Some things done in different times give us the impression of the whole dynasty in later generations.

Why is the Han Dynasty stronger than the Tang Dynasty? First of all, the Han Dynasty was a very powerful era, and many famous Han soldiers attacked the Huns. Huo Qubing, for example, is very powerful. He has been attacking the Huns, never giving up or giving in. I don't think it's necessary to say it in the prosperous Tang Dynasty. As we all know, we have the dynasty of Li Bai. The prosperity is extremely high, the politics is open and the people are open. The prosperity of Kaiyuan seems just around the corner.

We know that the Song Dynasty was rich and economically developed, because the Emperor of the Song Dynasty didn't pay much attention to agriculture. If we don't take the initiative to be pro-business, naturally our economy will develop rapidly.

Everything is developing very well. We can get a glimpse of the affluence of the Song Dynasty from The Riverside Scene at Qingming Festival. Now many things are slowly formed in the Song Dynasty. We also know that porcelain reached its peak in the Song Dynasty.

In the Ming Dynasty, Zheng He made seven voyages to the West. And finally Emperor Chongzhen committed suicide. Some people say that the Ming Dynasty was just too rigid and gradually perished, giving other nationalities an opportunity.

In the Qing dynasty, the country was closed to the outside world. In the end, Empress Dowager Cixi ceded our territory to foreign powers, which was a great shame in the history of China. Some people compare Cixi to Wu Zetian. I don't think Cixi deserves it at all.

Wu Zetian managed the country well, but Cixi only ceded the territory of our country and the territory of China to outsiders. What a historical sinner! What a dog!