辯正論 6.22

6.22

外五異曰（注老君降迹周王之代。三隱三顯五百餘年釋迦應生胡國之時。一滅一生壽唯八十）。

The External Fifth Difference states: (Note: Lord Lao descended into trace in the era of the Zhou kings, hiding three times and appearing three times across more than five hundred years; Śākya was born in response in the barbarian lands, passing away once and being born once, with a lifespan of only eighty.)