Taijitu prior to 1686. It combines several abstract shapes, including a "Taiji" symbol illustrating the mutual complement of man and woman. In socialist times, it was alternatively interpreted as two fish symbolizing vigilance, because fish never close their eyes. The modern symbol has also been widely used in martial arts, particularly t'ai chi ch'uan (Taijiquan), and Jeet Kune Do, since the 1970s. In this context, it is generally used to represent the interplay between hard and soft techniques. The dots in the modern "yin-yang symbol" have been given the additional interpretation of "intense interaction" between the complementary principles. Similarities can be
Yin and yang with fire, sky, the sun, masculinity and daytime. The yin-yang symbol, having no "officially standardized" rendition, has been the basis of much artistic variation, most of it "frivolous" (that is, "merely" artistic, with no philosophical/mystical meaning, e.g., tattoos). Yin and yang also applies to the human body. In traditional Chinese medicine good health is directly related to the balance between yin and yang qualities within oneself. If yin and yang become unbalanced, one of the qualities is considered deficient or has vacuity. In the "I Ching", originally a divination manual of the Western Zhou period (c. 1000–750 BC), yin and