EN 
Middle range theories consist of delimited sets of assumptions from which specific hypotheses could be logically derived and empirically tested, yet are sufficiently general to apply in a range of domains. Characteristically clear and simple, the ideas in middle range theories involve specified ignorance of what must be learned to build cumulative knowledge of the subject at hand. Strain and anomie, the unanticipated consequences of purposive social action, the self‐fulfilling prophecy, and the Matthew effect are a mere sample of the icons in Merton’s grand oeuvre.
Jennifer Lee (2021): The Legacy of Robert K. Merton: On Theories of the Middle Range. Sociological Forum, Series 'Legacies of Sociology’s Past' Online, 1-5 (Essay), ungated.
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