In his previous life, Shi Feiyang had delved into numerology, tracing it to its roots and analyzing its underlying logic.
Yin and yang, the five elements, Eight Trigrams, the heavenly stems, the earthly branches, and even the sixty-four hexagrams had originally been tools the Ancient Times' ancestors used to calculate astronomical phenomena and devise calendars. The mathematics, music, medicine, architecture, and other disciplines that developed later all lay within this framework.
While studying the relationship between the five elements and the five musical notes, he discovered that it was not simply a matter of forcing the five elements onto the five notes. The determination of pitches and tuning followed its own internal logic. His research took a turn into music, and there he discovered a name he had never encountered in textbooks or any of his extracurricular reading—Zhu Zaiyu.
Zhu Zaiyu belonged to the same generation as the Longqing Emperor, Zhu Zaigao, making him an uncle of sorts to the Wanli Emperor.
Using an enormous eighty-one-rod abacus, he calculated square and cube roots to twenty-five significant figures, devised twelve-tone equal temperament, precisely measured the density of mercury and other substances, designed the world's earliest pitch-setting instrument, made the earliest prototype of the piano, and established an outline for the study of dance... He was one of the greatest astronomers, historians, mathematicians, musicians, and dance scholars in the history of China...
At first, Shi Feiyang had been stunned by that enormous abacus, trying to imagine what such a thing would look like. The deeper he dug afterward, the more unfathomable the man seemed.
Unfortunately, he had been preparing for his high school entrance exams at the time. Music belonged neither to his schoolwork nor to numerology, so he treated it merely as extracurricular knowledge. Once he understood how the ancients determined