Acharya Prashant explains the meaning of the word 'guhya' as secret or hidden, like something that resides in a cave ('guha'), distinguishing it from 'jatil' which means complex. He states that while the mantras and Samhitas of the Vedas can be called complex from a linguistic or grammatical perspective, they are not 'guhya'. This term is specifically reserved for the Upanishads because they are not easily understood. The reason for this distinction is that other parts of the Vedas, like the Mantras, Samhitas, Brahmanas, and Aranyakas, primarily discuss the world ('sansaar') as it was in their time. The Upanishads, being the final part, do not talk about the world. The subject of the Vedas is not the world, not even Brahman or Atman, but 'Aham' (the 'I'). This is why the Upanishads are considered the essence ('saarbhoot') of the Vedas. The Upanishads constitute a very small part of the Vedas, less than one percent, like a few drops of essence extracted from a large substance. However, their relevance is eternal. The other parts of the Vedas, which discuss contemporary matters like gods, rituals, and worldly affairs, have become largely irrelevant over time as the world has changed. These parts may hold religious or archaeological value, but their spiritual significance has diminished. The Upanishads, on the other hand, address the fundamental, unchanging nature of man and his inner illusion, making them timeless and immortal. Acharya Prashant concludes that the Vedas will live on through the Upanishads. To truly understand the Upanishads, one must be willing to dissolve the self, as the fear of 'drowning' prevents true knowing. Knowledge must be lived, not just held in the mind. The fear of death is essentially the fear of losing worldly pleasures. Immortality, therefore, is the state where the fear of losing anything is gone.