Universal soul is one of the main Keystone of the philosophy and the thought of the Upanishad. Brahma satyam Jagat Mitya Jeevo Bramanah Parah talks about the impermenance of the body and its existence.
Fa Hien or Faxian who was a famous Chinese traveler, visited India during his reign of Chandragupta II. He came through land route and went back through sea route.