According to Zhou Dunyi's Taiji philosophy, the universe was created through the interaction of two opposing forces, known as yin and yang. These forces are represented by the symbol of the Taiji, a circle divided into two halves, one black and one white, with a small dot of the opposite color in each half.

In Taiji philosophy, yin represents the feminine, dark, and passive aspects of the universe, while yang represents the masculine, light, and active aspects. These two forces are constantly in a state of flux and balance, with neither one being dominant over the other. This balance is essential for the harmony and order of the universe.

The creation of the universe is believed to have occurred when the two forces of yin and yang came together in a state of perfect balance, giving birth to the Taiji symbol. This symbol then expanded and evolved, giving rise to the physical world and all its inhabitants.

As the universe continues to evolve, the interaction between yin and yang continues to shape and transform it. This is known as the principle of mutual transformation, where yin can transform into yang and vice versa. This process is seen in the changing of the seasons, the cycles of day and night, and the growth and decay of all living things.

Taiji philosophy also explains the evolution of the universe through the concept of Wuji, which is the state of infinite potential and emptiness that existed before the creation of the Taiji. Wuji is the source of all things and is believed to contain the seeds of yin and yang. From this state of Wuji, the Taiji emerged, giving rise to the physical world and all its complexities.

In conclusion, according to Taiji philosophy, the universe was created through the perfect balance of yin and yang, and its evolution is a continuous process of transformation and balance between these two forces. This philosophy emphasizes the interconnectedness and harmony of all things, and the importance of maintaining balance in order to achieve harmony and order in the universe.