According to Chapter 4, what specific signs of societal degradation prompt the incarnation of a saint?

Chapter 4 provides a detailed list of conditions that signify a decay in religion and society, which in turn calls for a saint to descend. These signs include Brahmins despising their own caste while Shudras try to become Brahmins, religious teachers being insulted, and a general disregard for religious teachings. The text mentions a time when every person considers themselves a scholar, leading to competition and disrespect. Further signs mentioned in Chapter 4 are the open consumption of liquor and meat by Brahmins, the growth of sectarian hatred, and the fatigue of Brahmins, ritualists, and Yogis with their respective spiritual practices.