The relationship between Chan Buddhism and Taoism is one that is deeply intertwined and has greatly influenced each other throughout history. Chan Buddhism, also known as Chinese Zen, is a school of Mahayana Buddhism that originated in China during the Tang dynasty (618-907 CE). Taoism, on the other hand, is a philosophical and religious tradition that originated in ancient China and is based on the teachings of Lao Tzu.

One of the main connections between Chan Buddhism and Taoism is their shared emphasis on the concept of non-duality. Both traditions reject the idea of a dualistic world where there is a clear separation between the self and the external world. Instead, they emphasize the importance of realizing the interconnectedness and unity of all things. This is reflected in the famous Chan saying, "The ten thousand things are one; the one is ten thousand things."

Another important aspect of the relationship between Chan Buddhism and Taoism is the influence of Taoist principles and practices on the development of Chan Buddhism. During the Tang dynasty, Buddhist monks in China were heavily influenced by Taoist teachings and incorporated many Taoist practices into their own meditation practices. This can be seen in the emphasis on spontaneity and naturalness in Chan Buddhism, which is a direct influence of Taoist principles.

Furthermore, many Chan masters were also well-versed in Taoist texts and teachings, and often incorporated Taoist concepts and terminology into their teachings. For example, the concept of "wuwei" (non-action) in Taoism is similar to the Chan idea of "wei wu wei" (action without action), which emphasizes the importance of non-striving and letting go of attachments.

In addition, both Chan Buddhism and Taoism place a strong emphasis on the practice of meditation. However, while Taoism views meditation as a means to achieve physical immortality, Chan Buddhism sees it as a path to spiritual enlightenment and liberation from suffering. Despite this difference in ultimate goals, the two traditions share many similarities in their meditation practices, such as the use of breath control and visualization techniques.

In conclusion, the relationship between Chan Buddhism and Taoism is one of mutual influence and shared principles. While they have distinct origins and ultimate goals, they have greatly influenced each other and continue to coexist and complement each other in modern times. Their shared emphasis on non-duality, meditation, and living in harmony with the natural world make them two closely related and deeply connected traditions in Chinese culture.