A term often used in linguistics and less often in semiotics (mostly in narrative analysis), which is the opposite of surface structure.
The deep structure is the subsurface, often hidden structure through which the surface structure, say the sentence or narrative, is generated.
The care to excavate the deep structure is in the focus of interest in linguistics practiced by Noam Chomsky and his followers, as well as in the scope of activities of narratologists such as Roland Barthes and Algirdas Julien Greimas. According to these theorists, one can see through an X-ray through a sentence or narrative and see the bare bones that support the verbal or textual figure.
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