Nelson Brissac is a professor at the São Paulo Catholic University's department of communication and semiotics, and curator of Arte Cidade.

Ary Perez and Denise Milan occupy a unique place within the Brazilian art scene. At a moment of nearly complete stagnation of aesthetic creation, they have taken up the development and systematization of the language of sculpture and art within the urban space. In the present work, the couple renders a marvelous and amazing articulation of apparently more intuitive sculptural procedures - such as, for example, the stone arrangement into an astronomical device - with geometric design "kits" indicating just how those elements can be viewed as lettering of an abstract language. From the Chicago planetarium to the interactive device installed in São Paulo, what stands out is the indication that artistic creation stems from conceptual and procedural achievements resulting from language consolidation. All of the history of art as well as of science and architecture is alluded to here.