🌿 Folk Prescriptions

In ancient times, East and West had different symbols for medicine. Chinese medicine uses the yin-yang fish, while European countries traditionally used the serpent-wound staff as their emblem.
The yin-yang fish, also known as the Taiji diagram, features black and white interlocking circles separated by an S-shaped curve, resembling two inverted fish. In Chinese cultural history, there are two series of Taiji diagrams: the five-layer Taiji and the yin-yang fish pattern. The five-layer Taiji first appeared in Zhou Dunyi’s Taiji Tu Shuo from the Northern Song Dynasty. The yin-yang fish pattern is even older. Recently, a stone artifact bearing a Taiji symbol was discovered at Leigudun in Suizhou City, Hubei Province. Dating back over 5,000 years to the era of the Divine Farmer, it is considered a primitive prototype of the Taiji diagram. The artifact is now preserved at the Suizhou Cultural Relics Administration. The Taiji diagram was originally devised by ancient philosophers, Daoists, and alchemists to illustrate the theory of yin and yang. In Wei Boyang’s Zhouyi Can Tongqi from the Eastern Han Dynasty, diagrams such as “Water and Fire Medical Corridor,” “Earth Receiving Heavenly Qi,” “Moon Receiving Sunlight,” “Ascending and Descending,” and “Yin-Yang Reflection” were included. These evolved through refinement and abstraction into the highly symbolic yin-yang fish Taiji diagram. It represents the ancient Chinese model for understanding the cosmos and the principles of change. The outer circle symbolizes Taiji or Wuji (the ultimate), indicating that all things in the universe originate from primordial qi and undergo continuous motion and cycles. Inside, the white fish on the left with its head upward represents yang, while the black fish on the right with its head downward represents yin. Each fish contains a small circle—the eye—symbolizing that yang contains yin and yin contains yang, with yang ascending on the left and yin descending on the right. The S-curve separating the two fishes illustrates that balance is not a rigid, symmetrical split like a knife cut or a scale balance, but a dynamic, ever-changing equilibrium where one diminishes as the other increases. The yin-yang fish Taiji diagram is a flat representation of the theory of yin and yang, embodying the wisdom of the Chinese nation. The diagram became standardized during the Southern Song Dynasty and exists today in two forms: east-west (yin and yang fish side-by-side) and north-south (yin and yang fish stacked vertically), with the east-west version being more common. Daoists, alchemists, physicians, and even Confucians adopted the Taiji diagram as their emblem, engraving it on Daoist temples, alchemical pills, classical texts, and beams of Confucian temples after the Song Dynasty. In 1937, Danish physicist Niels Bohr, whose quantum theory explanations were already highly refined, visited China and was deeply impressed by the dualistic concept of the Taiji diagram. He recognized a parallel between his principle of complementarity and Chinese philosophy, developing a lasting fascination with traditional Chinese culture. When awarded the Nobel Prize in Physics and required to design a family crest, he chose the Chinese Taiji diagram to represent opposing complementarity, personally inscribing a motto on it. Bohr believed there was profound consensus and resonance between ancient Eastern wisdom and modern Western science. The Taiji diagram once again attracted attention from the scientific community.
TCM, based on the theories of yin-yang and the five elements, naturally adopted the Taiji diagram as its emblem, though commonly referred to as the yin-yang fish in medical contexts. The Taiji diagram is often printed in medical texts, while in traditional Chinese pharmacies, a fish is hung beneath a string of ointments, pills, or incense—using the homophonic pun “yu” (fish) meaning “cure” (yù), and the two fish together forming a complete Taiji. Since fish never close their eyes, this also symbolizes doctors and pharmacists who must remain vigilant day and night, ready to provide care and medicine. Linking the yin-yang fish with medical ethics as a symbol makes the emblem even more meaningful.