Photo source: Wikimedia Commons, Kazimir Malevich
Kazimir Malevich (1879-1935) was a Russian painter best known for his contributions to Suprematism. Wikipedia says,
"Early on, Malevich worked in a variety of styles quickly assimilating the movements of Impressionism, Symbolism and Fauvism, and after visiting Paris in 1912, Cubism. Gradually simplifying his style, he developed an approach with key works consisting of pure geometric forms and their relationships to one another, set against minimal grounds." (Wikipedia: Kazimir Malevich, 7.18.21 UTC 22:19)The rest of this post is some quotes from Malevich.
Suprematism
"The rectangular picture-plane indicates the starting point of Suprematism; a new realism of color conceived as non-objective creation. The forms of Suprematist art live like all the living forms of nature. This is a new plastic realism, plastic precisely because the realism of hills, sky and water is missing." (Quoted in Artists on Art by Goldwater and Treves)
"The square is not a subconscious form. It is the creation of intuitive reason. The face of the new art. The square is a living, regal infant. The first step of pure creation in art." (From Cubism and Futurism to Suprematism, 1916)
"By Suprematism, I mean the supremacy of pure feeling in creative art. To the Suprematist the visual phenomena of the objective world are, in themselves, meaningless; the significant thing is feeling." (The Non-Objective World: The Manifesto of Suprematism, 1926)
Technique
"Everywhere there is craft and technique, everywhere there is artistry and form. Art itself, technique, is ponderous and clumsy and because of its awkwardness it obstructs that inner element." (Quoted in Futurism by Didier Ottinger)