Before the 20th century, people had different ideas about what made things beautiful. Aesthetics is the study of what makes things beautiful and how we can appreciate them. It's like when you draw a pretty picture or pick a favorite color. You are thinking about aesthetics.
In ancient times, people believed that beauty came from harmony and balance. They thought that objects and designs that were symmetrical, or the same on both sides, were the most beautiful. They also believed that beauty existed in nature, like with flowers, sunsets, and other natural things.
In the Middle Ages, people had different ideas about beauty. They thought that beauty was connected to religious ideas and beliefs. They believed that beautiful things should inspire people to be closer to God.
During the Renaissance, people started to think more about human beings and our place in the world. They began to focus more on individual perspectives of beauty. People started to think about what makes a person beautiful, not just what makes an object or design beautiful.
In the 18th and 19th centuries, people started to focus on the idea of the "sublime." The sublime was a sense of awe and wonder that people felt when they saw something that was both beautiful and terrifying, like mountains or stormy seas. This idea was popular in art and literature.
Overall, people have been thinking about aesthetics for a long time. Every culture and every period of history has had its own ideas about what makes things beautiful. It's fun to think about what you find beautiful and why!