Duality (of structure)
From Geography
This is the core concept of Gidden’s (Anthony Giddens) theory of structuration. In opposition to classical social theory which is characterized by a dichotomy of structure and agency, structuration theory argues that social structures are the medium and the outcome of human agency. all social practices are carried out under specific structural conditions. while at the same time structures are maintained and reproduced only through these social practices (Lippuner, R. & Werlen, B. (2009 page 1).
References:
Lippuner, R. & Werlen, B. (2009) Structuration Theory. In: International Encyclopedia for Human Geography. Elsevier.