Drawn on Marxian language and repurposed by Nicolas Bourriaud in his text, Relational Aesthetics, the term social interstices refers to a space that facilitates human social interaction. Marx refers to the term interstice as a pocket of trading activity that stands outside the capitalist framework. Similarly, social interstice as Bourriaud uses it references a similar defiance of the dominant system. In this case, social interstices are those spaces of free interaction that provide opportunities for social engagement outside of the norm.
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