Simmering beneath this essay we can detect the old feud between Concrete artists in São Paulo and the neo-Concrete movement in Rio de Janeiro, to which Oiticica belonged. At the time he wrote this essay, he had already created quite a number of group (and popular) projects. One of them was Apocalipopótese, an event that he and Rogério Duarte jointly wrote about. Oiticica’s essay mentions Duarte, who staged a performance on that occasion in 1968. The subject that Oiticica discusses here was one of the things that drove the two groups apart—having originally been united by a shared constructivist reading of art via geometric abstraction.
In “O objeto” , an article published in A & D magazine (issue # 20, November–December 1956), the artist and art critic Waldemar Cordeiro advocated the autonomy and universality of art. His argument was based on the concept of “corpus solidum.” Some years later the critic Ferreira Gullar published his rebuttal, “Teoria do não-objeto”  in the Sunday Supplement of the Jornal do Brasil; Gullar’s theory was a key contribution to the II Exposição Neoconcreta, which took place in 1960 in Rio de Janeiro. The “non-object” does not fit into any of the traditional categories in painting or sculpture, and thus relies on the concept of “quasi corpus.” There are two other crucial essays that must be read in order to follow Oiticica’s writing, both of them by Ferreira Gullar: “Do cuadro ao não-objeto” , and “Cor e estrutura-cor” .
Hélio Oiticica (1937–80) was a Brazilian Neo-Concrete artist. He started studying painting with Ivan Serpa in 1954 at the Museu de Arte Moderna do Rio de Janeiro. He later joined the Grupo Frente and the Neo-Concrete movement. In addition to his geometric paintings, which he worked on while he was studying with Serpa and was a member of the Grupo Frente, Oiticica produced performance and participatory art. His Parangolés (1964)—capes made with fabrics and recycled materials—were worn by the Mangueira Samba School during their performances. Oiticica also created immersive spaces, such as Nucleus (1959–60), which was an installation constructed from suspended painted wooden slats inspired by the Constructivism of Piet Mondrian. In 1967 Oiticica created the immersive environment Tropicália at the Museum of Modern Art in Rio de Janeiro. Tropicália was an installation consisting of rooms with plants and materials such as water, sand and stones, a parrot, a television set, and various other elements that were representative of Brazilian popular culture. The environment was designed to promote sensory stimulation. Oiticica applied the same principles to Eden, the installation he created in 1969 at the Whitechapel Gallery in London. The name Tropicália was used by Brazilian musicians to describe a new style that combined international music and pop with traditional Brazilian music. The term “Tropicália” was absorbed into popular Brazilian culture and came to signify a uniquely Brazilian essence. In 1970 Oiticica took part in the group exhibition Information at the Museum of Modern Art in New York.