Chinese sun and moon mirrors being hung round the neck, or because necks are concave things. Liu An's (c. 139 BCE) "Huainanzi" "Masters of Huainan", which is a compendium of writings from various schools of Chinese philosophy, was the first text to record "fangzhu" dew-collectors. Two "Huainanzi" chapters metaphorically use "sun and moon mirrors" to exemplify "yang" and "yin" categories and elucidate the Chinese notion of "ganying" "cosmic resonance" through which categorically identical things mutually resonate and influence each other. The "yángsuì" 陽燧 "burning-mirror" is "yang", round, and sun-like; the "fāngzhū" 方諸 "square receptacle" is "yin", square, and moon-like. The first context describes "yangsui" and
Taijitu has its nature. Instead of usual "Taiji" translations "Supreme Ultimate" or "Supreme Pole", Adler uses "Supreme Polarity" (see Robinet 1990) because Zhu Xi describes it as the alternating principle of "yin" and "yang", and ... insists that "taiji" is not a thing (hence "Supreme Pole" will not do). Thus, for both Zhou and Zhu, "taiji" is the "yin-yang" principle of bipolarity, which is the most fundamental ordering principle, the cosmic "first principle." "Wuji" as "non-polar" follows from this. Since the 12th century, there has been a vigorous discussion in Chinese philosophy regarding the ultimate origin of Zhou Dunyi's diagram. Zhu