Created in 1964, Smithson's Untitled is a low trapezoidal form that sits directly on the floor, constructed from formica and mirrors. Two sets of mirrors are installed along both parallel sides of the form. The top mirrors reflect the floor and the bottom mirrors reflect the ceiling, inverting expectations of traditional spatial relationship. In describing Smithson's use of mirrors in his sculptures from this period, the art historian Robert Hobbs wrote, "If art is concerned with mirroring the world, then Smithson turned his art into a reflective surface that literally does image the world: it mirrors its actual circumstances, making the space around it part of the sculpture."⁠
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In the margins of a related drawing from 1964, Smithson wrote, "In the words of Jorge Luis Borges, I have set out 'to design that ungraspable architecture.'" The Argentinian writer Jorge Luis Borges was an influential thinker for Smithson and this phrase comes from Borges' 1960 poem "Mirrors." The poem deals with the disturbing infinite nature of reflection in mirrors, generating both physical and psychological illusions.⁠ Smithson's mirrored sculptures from the mid-1960s explore these multifaceted questions, manipulating the viewer's sense of self and reality.
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