Waldemar Cordeiro—landscape designer, painter, electronic artist, theorist, and critic—was Brazilian on his father's side and Italian on his mother's. He studied in Italy and traveled in 1946 to Brazil, where he settled in São Paulo. In the 1950s he founded the Ruptura Group and wrote its manifesto, thus becoming a central figure in São Paulo's Concrete art movement. Cordeiro defended Concrete art's mathematical and rational principles in the face of the Rio de Janeiro Neo-Concrete group, which advocated a more sensorial and cognitive Geometric Abstraction. The concept behind the series Idéia visível (Visible Idea) clearly demonstrates that Cordeiro considered the object a mere concrete abstraction.