“The art of painting is the Art of hollowing out a canvas.”

Joseph Kosuth in: Arthur R. Rose, “Four Interviews,” Arts Magazine (February, 1969).

Las artes (pintura, poesía, etc.) no son solo éstas. Artes son también comer, beber, caminar: todo acto es un arte.
Source: Aphorisms (2002), p. 60

Source: Color, Format and Abstract Art' (1977), pp. 99 – 105

Such were the doctrines of every art teacher only twenty or thirty years ago.
1.
1900 - 1920, On Primitive Art – Emil Nolde, 1912

Daniel Buren, Olivier Mosset, Michel Parmentier and Niele Toroni, at the Paris Biennale in October 1967. Translated and cited in: Lucy R. Lippard, Six Years: The Dematerialization of the Art Object from 1966 to 1972, New York: Praeger, (1973), p. 30.
1960s

1910s
Source: 'Merz Painting' (1919); as quoted in I is Style, ed. Siegfried Gohr & Gunda Luyken, NAI Publishers, Rotterdam 2000, p. 91.

As quoted in "Grace Hartigan, 86, Abstract Painter, Dies" in The New York Times (18 November 2008)

X magazine (1959-62)
Context: The Art of painting is itself an intensely personal activity. It may be labouring the obvious to say so but it is too little recognised in art journalism now that a picture is a unique and private event in the life of the painter: an object made alone with a man and a blank canvas... A real painting is something which happens to the painter once in a given minute; it is unique in that it will never happen again and in this sense is an impossible object. It is judged by the painter simply as a success or failure without qualification. And it is something which happens in life not in art: a picture which was merely the product of art would not be very interesting and could tell us nothing we were not already aware of. The old saying, “what you don’t know can’t hurt you”, expresses the opposite idea to that which animates the painter before his canvas. It is precisely what he does not know which may destroy him.

Source: Quotes, 1960 - 1970, Questions to Stella and Judd' - September 1966, p. 122