What philosophical teachings on duality and non-duality are presented in Chapter 14?

Chapter 14 provides deep philosophical insights into the concepts of oneness (non-duality) and duality. It teaches that the same Essence present in one's own body is present throughout the entire universe. True wisdom is achieved by surrendering to this Essence, which leads to seeing oneness in all. Conversely, the chapter defines the intellect that establishes duality, or manifoldness, as pure ignorance that traps one in the cycle of birth and death. Attaining oneness is described as turning away from this ignorance. According to the teachings in Chapter 14, even a trace of difference in the mind prevents the state of non-duality, as everything from the highest creator, Brahma, down to a blade of grass is ultimately pervaded by the singular reality of Brahman.