A primary concern of Feldman's during the last decade of his life was what he called the 'scale' of his composition. He pointedly distinguished between the words 'form' and 'scale.' He said that up to about an hour in length, the ear wants to hear 'form.' After an hour it's 'scale.' As a comparison, Feldman told of visiting Mark Rothko one day when an assistant was stretching and restretching a canvas to slightly different sizes. "Rothko was standing some distance away, ... deciding whether to bring the canvas down an inch or so, or maybe even a little bit higher."

 Rothko's scale ... removes any argument over the proportions of one area to another, or over its degree of symmetry or asymmetry. The sum of the parts does not equal the whole; rather, scale is  discovered and contained as an image. It is not form that floats the painting, but Rothko's finding that particular scale which suspends all proportions in equilibrium. [Morton Feldman Essays, Walter Zimmermann, ed. (Kerpen, Germany: Beginner Press, Germany 1985) p126]

 Where Rothko found means to make color alone the voice of mood and emotion, Feldman found ways to make sound alone, not its forms or progressions, the means to the same end. In his late music Feldman aspired to a condition whereby the space of a canvas is a paradigm for the length of a composition

from Louis Goldstein “Morton Feldman and The Shape of Time” in Perspectives on American Music Since 1950, edited by James R. Heintze (New York and London: Garland Publishing Inc., 1999)