Pier Paolo Calzolari—whose practice spans painting, sculpture, performance, architecture, and video, as well as the inclusion of live people and animals—is recognized worldwide as a leading figure of the Arte Povera movement. Bringing quotidian ritual into the realm of aesthetic experience and focusing on the fragility of objects and materials, Calzolari attempts to saturate the senses in order to reveal the nature of abstract thought and the essence of matter. In 1966-67, he produced his first multi-media performance piece, Ιl filtro e benvenuto all’ angelo, which incorporated audience participation, light, darkness, grass, and birds. Calzolari invited spectators to dress and undress, to move freely among the flying birds, and to lie on the grass. Anticipating contemporary social sculpture, Calzolari called this piece an “activation of space.”