The material world is temporary and full of misery. It operates under three modes: goodness, passion, and ignorance, as explained in the Bhagavad-gita (7.14). These modes condition the soul and create the illusion of separate existence from the Supreme. The Bhagavad-gita (8.15-16) describes the material world as a prison where souls suffer due to forgetfulness of their spiritual nature. The Bhagavad-gita (13.8-12) and (14.5-9) further elaborate on these three modes. Perfect Questions Perfect Answers (Chapter 4) compares the material world to a prison.