Based on the text, what does Chapter 20 say about the futility of intellectualism without devotion when trying to understand spiritual truths?

Chapter 20 makes a strong case against relying solely on intellect to grasp spiritual truths. It uses the example of interpreting the Upanishads, which are described as the treasure of the four Vedas. The chapter posits that a person might proclaim, 'I am a scholar; by my own efforts I will comprehend the Upanishads,' but this will not succeed even at the end of an era. The text explicitly states that this is a 'difficulty without Guru's grace' and that 'the hidden truth does not come to hand.' In contrast, for a person who is humble, detached, and attached to the Guru's feet, there is 'not even a bit of difficulty.' This teaching from Chapter 20 emphasizes that devotion and surrender to a Guru are essential prerequisites, without which intellectual effort alone is futile in the quest for Self-knowledge.