Lion was one of the motifs used in Ashokan pillars. Lion is a solar symbol and it also represents the Buddha, as he is referred to as Sakyasimha which also means a lion among the Sakyas.
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.