How does the concept of duality contribute to the cycle of birth and death, and what is the solution?

Chapter 37 explains that an obsession with duality, or holding even the slightest view of difference, is a direct cause of fear and suffering. This perception of manifoldness is what traps an individual in the cycle of birth and death, where destruction and creation will constantly follow them. The solution proposed is to serve the non-distinguished state, where fear does not exist. This state is achieved by acquiring the science of the oneness of Brahman and the Self through the Guru, which removes ignorance and the knowledge of manifoldness, thereby ceasing the cycle of birth and death.