And then about whether or not to work from a given in nature. In my view, you [Van Doesburg] define this in a rather narrow sense. In the main, I do agree with you that the destruction of the natural, and it reconstruction, must be accomplished according to a spiritual image, but I believe that we should take a broad view here. What is natural does not have to be a representation of something. I'm now working on a thing that is a reconstruction of a starry sky ['Composition, Checkerboard Dark Colours', 1919] and yet I'm making it without a given from nature. Someone who says he uses a theme from nature can be right, but also someone who says he uses nothing at all.
In a letter to Theo van Doesburg, 18 April 1919; as quoted in Mondrian, -The Art of Destruction, Carel Blotkamp, Reaktion Books LTD. London 2001, pp. 125-6