Retrieval Lost to Time: A Typology of Structural Erasure in Intellectual and Political Memory

This study defines a five-mode typology of structural erasure that explains how ideas, people, and movements disappear from collective memory. The modes, Silencing, Reclassification, Compression, Substitution, and Tactical Forgetting, describe distinct points where knowledge retrieval fails. Drawing on five historical cases, Sophie Germain, Rosalind Franklin, María Elena Moyano, Nwanyeruwa, and Paul Robeson, the paper demonstrates that erasure is not accidental but structural, reflecting patterns of exclusion embedded in institutions and archives. It introduces the Retrieval Integrity Index, a quantitative proof of concept showing that erasure leaves measurable traces in visibility, coverage, substitution, and volatility data. By linking cultural memory studies, feminist epistemology, and decolonial theory, the study provides a diagnostic framework for recognizing and repairing loss within systems of knowledge. The findings show that preventing erasure requires transparent archival practices, inclusive historiography, and equitable design in digital memory systems.