Conceptual art

“Conceptual art, also referred to as conceptualism, is art in which the concept(s) or idea(s) involved in the work take precedence over traditional aesthetic, technical, and material concerns. Some works of conceptual art, sometimes called installations, may be constructed by anyone simply by following a set of written instructions. This method was fundamental to American artist Sol LeWitt‘s definition of conceptual art, one of the first to appear in print: In conceptual art the idea or concept is the most important aspect of the work. When an artist uses a conceptual form of art, it means that all of the planning and decisions are made beforehand and the execution is a perfunctory affair. The idea becomes a machine that makes the art. Tony Godfrey, author of Conceptual Art (Art & Ideas) (1998), asserts that conceptual art questions the nature of art, a notion that Joseph Kosuth elevated to a definition of art itself in his seminal, early manifesto of conceptual art, Art after Philosophy (1969). The notion that art should examine its own nature was already a potent aspect of the influential art critic Clement Greenberg‘s vision of Modern art during the 1950s. With the emergence of an exclusively language-based art in the 1960s, however, conceptual artists such as Art & Language, Joseph Kosuth (who became the American editor of Art-Language), and Lawrence Weiner began a far more radical interrogation of art than was previously possible (see below). One of the first and most important things they questioned was the common assumption that the role of the artist was to create special kinds of material objects. … Conceptual art emerged as a movement during the 1960s – in part as a reaction against formalism as then articulated by the influential New York art critic Clement Greenberg. According to Greenberg Modern art followed a process of progressive reduction and refinement toward the goal of defining the essential, formal nature of each medium. Those elements that ran counter to this nature were to be reduced. The task of painting, for example, was to define precisely what kind of object a painting truly is: what makes it a painting and nothing else. As it is of the nature of paintings to be flat objects with canvas surfaces onto which colored pigment is applied, such things as figuration, 3-D perspective illusion and references to external subject matter were all found to be extraneous to the essence of painting, and ought to be removed. …”
Wikipedia
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Sol LeWitt, Sentences on Conceptual Art, 1968