Since the 1960s, paintings, prints, photographs, sculptures, installations, and books have been among the media through which Allen Ruppersberg explores the intersection of art, literature, and life. Like those of Allan Kaprow, Ruppersberg’s projects are participatory, anticipating the ideas of Rirkrit Tiravanija, Carsten Höller, and other 1990s practitioners of Relational Aesthetics. Ruppersberg's installation The Never Ending Book Part 2/Art and Therefore Ourselves (2009) was a selection of thousands of photocopied pages from the artist’s collection of books, which he installed in a theatrical environment of props and posters; the pages were stacked in boxes and free for viewers to take home and create their own unique “books”.