Groupe de Recherche d’Art Visual

Groupe de Recherche d’Art Visuel (GRAV) (Research Art Group) was a collaborative artists group in Paris that consisted of eleven opto-kinetic artists, like François Morellet, Julio Le Parc, Francisco Sobrino, Horacio Garcia Rossi, Yvaral, Joël Stein and Vera Molnár, who picked up on Victor Vasarely's concept that the sole artist was outdated and which, according to its 1963 manifesto, appealed to the direct participation of the public with an influence on its behavior, notably through the use of interactive labyrinths.

GRAV was active in Paris from 1960 to 1968. Their main aim was to merge the individual identities of the members into a collective and individually anonymous activity linked to the scientific and technological disciplines based around collective events called Labyrinths.

Their ideals enticed them to investigate a wide spectrum of kinetic art and op art optical effects by using various types of artificial light and mechanical movement. In their first Labyrinth, held in 1963 at the Paris Biennale, they presented three years work based on optical and kinetic devices. Thereafter they discovered that their effort to engage the human eye had shifted their concerns towards those of spectator participation; a foreshadow of interactive art.

In 1963 GRAV produced a labyrinth for the third Paris Biennial that invited viewers to walk through twenty environmental experiences. Made up of wall mounted reliefs, light installations and mobile bridges in different rooms the labyrinth was meant to invoke different viewer reactions. GRAV argued that viewers' reactions had social implications and the group defined different types of audience interaction with their art, such as: "perception as it is today", "contemplation", "visual activation", "active involuntary participation", "voluntary participation" and "active spectatorship". GRAV published the Assez des Mystification ("Enough Mystification") manifesto alongside the labyrinth, stating that:

If there is a social preoccupation in today's art, then it must take into account this very social reality: the viewer.

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