<human>:  I have a question about the Chinese philosopher Ban Zhao. What is the yin-yang symbol?
<bot>: The yin-yang symbol is a symbol of the yin-yang philosophy. It represents the balance of yin and yang, the two fundamental forces of the universe. Yin is the dark side of the universe, and yang is the light side. The yin-yang symbol is often used to represent the relationship between the two.