["The British Journal of Sociology, Volume 77, Issue 2, Page 201-213, March 2026. ", "\nABSTRACT\nSociologists of knowledge production have long explored how scholars tackle empirical, methodological, and theoretical challenges. This article highlights a parallel process: the accumulation of moral justifications for pursuing knowledge in specific fields, which we term normative cumulation. As researchers face normative objections and dilemmas, they develop new moral justifications for their work. Researchers' interpretive work leads some justifications to institutionalize and accumulate over time. These justifications may continue to coexist within the same scholarly community. We examine 20th‐century American family demography as a case study, tracing historically how scholars justified their nascent scholarship through moral arguments linked to perceived social goods that demography produces. Over the history of family demography's development, diverse moral frameworks emerged, coexisting to justify family demographers' work. The article analyzes how shifting moral justifications in twentieth‐century American family demography diversified the field's approach, influencing its research agendas and potential societal roles.\n"]