Washington — Descriptions of economic inequality predate the theories that historians and other social scientists have created to explain it. And clearly such inequalities have not disappeared, despite both the advancement of theories of why economic development happens and sharp critiques of the concept.

So what have such theories added to our understanding of why some are rich and some are poor? In her presidential address at the American Historical Association’s annual meeting here, Barbara S. Weinstein, a professor of history at New York University and the 2007 association president, gave listeners a tour of both the advancement of theories of development and the fierce critiques of it.

“What do we lose,” she asked, “if we give up the idea of development?”

Her talk, titled “Developing Inequality,” sought a synthesis of sorts between the notion of progress (with its winners and losers) and the critiques of it that seek to unpack the complexities of race, gender, culture, and location in explaining wealth and poverty.

Drawing upon her own work in Brazil, tracing the history of power imbalances between São Paulo and the rest of the nation, Ms. Weinstein embedded her critiques of development theory and its critics into a rich and nuanced reading of haves and have-nots in that Latin American nation.

Her research and thought on those issues, she concluded, led her to urge that scholars focus on the “walls and borders” between status groups and how those groups police their edges. —Richard Byrne