Final answer:
The thematic topic most prevalent is The American Dream, which is evidenced by discussions on its role in society, impact on social mobility, and future in the context of historical and current societal conditions.
Step-by-step explanation:
From the provided information, the thematic topic that is emerging the most is The American Dream. This theme is discussed in various contexts, such as sociological theories, economic systems, the struggle for civil rights, and the future of American culture. The passages prompt discussions on the role of social mobility, systems of inequality, and the changing societal conditions that may impact individuals' pursuit of the American Dream. The American Dream encapsulates themes of success, opportunity, and the pursuit of prosperity through hard work. It also brings into question the attainability of this dream within different social classes and extends into analyses of how historical and current events shape the conception of this dream.