Why is our aesthetics called beauty by opposites? What are the historical reasons?

The ancient Greek philosopher Pythagoras once said, "The lines of beauty and all other forms of beauty must have symmetrical forms." The study of symmetrical beauty in ancient China was also amazing. For example, the Forbidden City, a treasure of China architecture. The Forbidden City is a great pioneering work in ancient China, which fully shows the wisdom of the ancient people in China and the profound aesthetic taste of the ancient people in China. Because the builders of the Forbidden City arranged all the buildings in a symmetrical way according to etiquette, this unified treatment of overall layout and architectural modeling made people experience a harmonious overall beauty and symmetrical beauty. In the hierarchical feudal society, symmetry not only exists as a kind of beauty, but also embodies the idea of respecting people and people. Through the understanding of ancient architecture in China, we can appreciate a historical connotation of symmetrical beauty. Symmetrical beauty embodies China's pursuit of beauty in ancient times, and so does modern life.