Visionary architecture is a design that only exists on paper or displays idealistic or impractical qualities. The term originated from an exhibit at the Museum of Modern Art in 1960. Visionary architects are also known as paper architects because their improbable works exist only as drawings, collages, or models. Their designs show unique, creative concepts that are unrealistic or impossible except in the design environment. Traditionally, the term visionary refers to a person who has visions or sees things that do not exist in the real world, such as a saint or someone who is mentally unbalanced. Thus, visionary architecture as a label is somewhat pejorative and has been used to marginalize paper architects from the mainstream. However, an article in Forbes noted, "Whereas ordinary architecture literally shapes the way in which we live, unrealized plans and models provide infrastructure for our collective imagination. They are meeting places for conversation." Visionary architecture was discussed and celebrated at the Architecture of Disbelief symposium at Cornell University in 2008. Prominent modern and pre-modern visionary architects include Etienne-Louis Boullée, Peter Eisenman, Zaha Hadid, Rem Koolhaas, Daniel Libeskind, Antonio Sant'Elia, and Lebbeus Woods. History and early works During the Renaissance, building styles evolved rapidly because of the introduction of perspective. This discovery allowed architects to experiment with imaginary architectural scenes. While many architects wrote on the subject, others articulated their concepts and ideas in their drawings. In the 16th century, a Dutch painter and architect, Jan Vredeman de Vries, produced numerous engravings that portrayed new forms of architecture. His architectural designs were pure fantasy and imagination—and avant-garde architectural spaces. Most architects imagine, see, and define buildings by fabricating models that can be scaled up and down, turning abstract architectural sketches into solid three-dimensional buildings. When turned into scaled models, visionary designs were considered utopian and fantastic. Rather than bringing the building into existence, visionary architects use scale models to make the building speak through a sense of fantasy and symbolic meanings. Some visionary architects skipped the model process entirely, believing that drawing is "the highest form and clearest expression of architecture." Giovanni Battista Piranesi was one of the greatest printmakers of the 18th century. Piranesi made prints of his architectural drawings that show his mastery of imagined spaces. Piranesi's drawings are visionary architecture because they included unique and intricate details that were only achievable in drawings and would be lost in translation to physical