Dear Does [Theo van Doesburg], thank you for your letter... I was glad to know that in principle you are in favor of the diamond hanging [Mondrian's painting, hanging in a rhombus] and I think that in practice you will approve of this method for some of my things. You look at the thing [painting] itself, and not only the outward appearance..

In a letter to Theo van Doesburg, 3 March 1919; as quoted in Mondrian, -The Art of Destruction, Carel Blotkamp, Reaktion Books LTD. London 2001, p. 122