an approximate equal temperament system was recommended by He Chengtian as early as the 5th century a.D. but Zhu Zaiyu was the first to arrive at the correct mathematical solution in a treatise of 1584.

• 早在公元5世纪何承天就提出了类似平均律的乐律，而朱载堉于1584年第一个在论文中用等比级数平均划分音律。