Sima Qian stated that Laozi grew weary of the moral decay of life in Chengzhou and noted the kingdom's decline. He ventured west to live as a hermit in the unsettled frontier at the age of 80. At the western gate of the city (or kingdom), he was recognized by the guard Yinxi. The sentry asked the old master to record his wisdom for the good of the country before he would be permitted to pass. The text Laozi wrote was said to be the "Tao Te Ching", although the present version of the text includes additions from later periods. In some versions of the tale, the sentry was so touched by the work that he became a disciple and left with Laozi, never to be seen again. Laozi's disciples Yinxi and Wenzi went on to write their own works, the "Guan Yi" and "Tongxuan zhenjing" respectively.