The Brazilian artists in this room, Hélio Oiticica and Lygia Clark, are exploring ideas of interactivity and viewer participation. Oiticica’s large installation Project FILTRO – for Vergara, New York 1972, invites the viewer to step inside. Oiticica invented his own personal classification system to replace traditional categories of painting, sculpture and so on. Project FILTRO belongs to a type of art that he classified as Penetrable: in translation, something that can be penetrated or entered into. Drawing on both the poverty and the vibrancy of the artist’s native Rio de Janeiro, Project FILTRO is a multi-sensory experience: the viewer moves through a labyrinth of exotic colours and textures, hearing recordings of poetry along the way, and even receiving a drink of orange juice at the end of the journey.

Like Oiticica, Clark explodes the idea of the art object as something for display only. Her Sensorial Objects 1966, made up of soft, organic shapes and materials, are offered to the viewer to touch or wear. Dialogue Goggles 1968, a pair of connected diving goggles, limits the visual field of the two participants to eye-to-eye contact, isolating sight from the other senses and enforcing an intense engagement with the other person. In these works, the object itself is of secondary importance to the sensory experience. The work can only exist when participants interact with the object provided: as Clark put it, the artist becomes a ‘proposer’ rather than the creator of a finished work. Since both these artists use inexpensive local materials and everyday objects in their work, they also raise questions about the commercial value of the art object.