In the mid-1960s, Bruce Nauman began making sculptural casts, questioning several of the assumptions that have attended the process throughout its history. He rejected the traditional use of a mold in the production of a technically perfect cast object. In Nauman’s earliest extant sculptures of 1965—a group of 11 elongated, vaguely anthropomorphic fiberglass works—he described his process as "making a mold, taking the two halves and putting them together to make a hollow shape and turning it inside out." In these early pieces, the artist was testing the notion of sculpture as a medium of solid, durable forms, thus turning the assumptions of sculpture, as well as the form, inside out.