Which among the following is the keystone of the philosophy and thought of the Upanishads?

• A. Universal God
• B. Universal Knowledge
• C. Universal Truth
• D. Universal Soul

Answer: (D)

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.