Overview
A rhizome is a concept in post-structuralism describing a nonlinear network that "connects any point to any other point". It appears in the work of French theorists Deleuze and Guattari, who used the term in their book A Thousand Plateaus to refer to networks that establish "connections between semiotic chains, organizations of power, and circumstances relative to the arts, sciences and social struggles" with no apparent order or coherency. A rhizome is purely a network of multiplicities that are not arborescent (tree-like, or hierarchical, e.g. the idea of hypertext in literary theory) with properties similar to lattices. Deleuze referred to it as extending from his concept of an "image of thought" that he had previously discussed in Difference and Repetition.
As a mode of knowledge and model for society
Deleuze and Guattari use the terms "rhizome" and "rhizomatic" (from Ancient Greek ῥίζωμα, rhízōma, "mass of roots") to describe theory and research that allows for multiple, non-hierarchical entry and exit points in data representation and interpretation. In A Thousand Plateaus, they place it in opposition to an arborescent (hierarchic, tree-like) use of concepts, which works with dualist categories and binary choices. A rhizome works with planar and trans-species connections, while an arborescent model works with vertical and linear connections. Their use of the "orchid and the wasp" is taken from the biological concept of mutualism, in which two different species interact together to form a multiplicity (i.e. a unity that is multiple in itself). Hybridization and horizontal gene transfer are also rhizomatic in this sense.
Rather than narrativize history and culture, the rhizome presents history and culture as a map or wide array of attractions and influences with no specific origin or genesis, for a "rhizome has no beginning or end; it is always in the middle, between things, interbeing, intermezzo." The planar movement of the rhizome resists chronology and organization, instead favoring a nomadic system of growth and propagation.
In a rhizome, "culture spreads like the surface of a body of water, spreading towards available spaces or trickling downwards towards new spaces through fissures and gaps, eroding what is in its way. The surface can be interrupted and moved, but these disturbances leave no trace, as the water is charged with pressure and potential to always seek its equilibrium, and thereby establish smooth space."
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