Gu Qin is a type of traditional oriental instrument. GuQin started with 5 strings, of oriental 5 elements. At around 1000bc, King Wen added another string to 6 and finally King Wu added the 7th string. Naming it the Wen Wu 7 String Instrument (文武七弦琴). This can be referred to an older literature in Book of Changes, Lao Zi stated 5 sounds makes one deaf (五音令人耳聋).