Mathematics and art through the strings as with a bird cage and to see one form within another which excited me." The artists Theo van Doesburg and Piet Mondrian founded the De Stijl movement, which they wanted to "establish a visual vocabulary elementary geometrical forms comprehensible by all and adaptable to any discipline". Many of their artworks visibly consist of ruled squares and triangles, sometimes also with circles. De Stijl artists worked in painting, furniture, interior design and architecture. After the breakup of De Stijl, Van Doesburg founded the Avant-garde Art Concret movement, describing his 1929–1930 "Arithmetic Composition", a series of four black
Theo van Gogh (art dealer) letters Vincent wrote during his life were to Theo, including his first and his last letters. It is largely thanks to Theo and his wife that these letters are available today. Hardly any of Theo's letters remain because Vincent failed to keep them. The letters have been collected and published in book form as "The Letters of Vincent van Gogh". The relationship between the two brothers was the subject of the movie "Vincent & Theo" (1990), directed by Robert Altman. It also formed an important part of the film "Lust for Life" (1956), which was directed by Vincente Minnelli. Theo