Chapter 14 mentions that 'the soul is the knower, and Brahman is the object of knowledge.' How does this perceived difference create a problem, and what is the solution?

This perceived distinction between the soul as the 'knower' and Brahman as the 'object of knowledge' is the very essence of duality that the teachings seek to correct. Chapter 14 explains that this sense of difference, even a trace of it, creates a 'mine of non-unity' and 'immediately produces manifoldness, which is the cause of birth and death.' The solution is the complete vanishing of the 'darkness of ignorance.' When this happens, the entire world of separation vanishes, and one's sight becomes filled with the oneness of their true nature. The text uses the analogy of pure water merging with pure water to illustrate how, upon gaining true knowledge, the identification of any difference ceases to exist.