Taijitu the Tibetan designs have three or four swirls (representing the Three Jewels or the Four Noble Truths, i.e. as a triskele and a tetraskelion design), Lai Zhide's taijitu has two swirls, terminating in a central circle. The Ming-era design of the taijitu of two interlocking spirals has been reported as "yin-yang symbol" in the first half of the 20th century. The flag of South Korea, originally introduced as the flag of Joseon era Korea in 1882, shows this symbol in red and blue. This was a modernisation of the older (early 19th century) form of the Bat Quai Do used
Taijitu the 16th century. The original description of a "taijitu" is due to Song era philosopher Zhou Dunyi (1017–1073), author of the "Taijitu shuo" "Explanation of the Diagram of the Supreme Ultimate", which became the cornerstone of Neo-Confucianist cosmology. His brief text synthesized aspects of Chinese Buddhism and Taoism with metaphysical discussions in the "Yijing". Zhou's key terms Wuji and Taiji appear in the opening line , which Adler notes could also be translated "The Supreme Polarity that is Non-Polar". Non-polar ("wuji") and yet Supreme Polarity ("taiji")! The Supreme Polarity in activity generates "yang"; yet at the limit of activity it