In Taoist-Confucian cosmology, the concept of Taiji refers to the ultimate source and principle of all things in the universe. It is often depicted as a circle with a black and white swirl, representing the interplay and balance of opposing forces.

According to the philosophy of Taiji, everything in the universe is made up of two complementary and interconnected energies known as yin and yang. These energies are constantly in a state of flux, with one always transforming into the other. This dynamic interplay is what gives rise to all phenomena and is the foundation of the natural world.

In the Taoist tradition, Taiji is seen as the source of all creation and the origin of the Tao, the underlying principle of the universe. It is believed that the Tao manifests itself in the form of yin and yang, and through their harmonious interplay, all things are brought into being.

In Confucianism, Taiji is also a central concept, but it is viewed more as a moral and ethical principle. Confucianism emphasizes the importance of maintaining balance and harmony in all aspects of life, and the concept of Taiji is seen as a guide for achieving this. By understanding and following the natural balance of yin and yang, one can achieve inner harmony and live in accordance with the Tao.

In both Taoism and Confucianism, the concept of Taiji is closely linked to the idea of qi, or vital energy. It is believed that the interplay of yin and yang gives rise to qi, which flows through all living beings and the natural world. By cultivating and balancing one's qi, one can achieve physical, mental, and spiritual well-being.

Overall, the concept of Taiji in Taoist-Confucian cosmology represents the fundamental principle of balance and harmony in the universe. It serves as a reminder to live in harmony with the natural world and to strive for balance in all aspects of life. By understanding and embodying the concept of Taiji, one can achieve a deeper understanding of the interconnectedness of all things and live in alignment with the Tao.