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.
The Mauryan art is believed to be inspired from Achaemenid or Persian influence. We can find a lot of similarities in terms of form and style in the inscriptions of Ashoka and the Persian king Darius.