You should remember that my things are still intended to be paintings, that is to say, they are plastic representations, in and by themselves, not pa… - Piet Mondrian

Well, I think my paintings are fast enough already...

the Cubists in Paris made me see that there was also a possibility of suppressing the natural aspect of form. I continued my research by abstracting the form and purifying the colour more and more. While working, I arrived at suppressing the closed effect of abstract form, expressing myself exclusively by means of the straight line in rectangular opposition; thus by rectangular planes of colour with white, grey and black. At that time, I encountered artists with approximately the same spirit, First Van der Leck, who, though still figurative, painted in compact planes of pure colour. My more or less cubist technique - in consequence still more or less picturesque - underwent the influence of his exact technique. Shortly afterwards I had the pleasure of making the acquaintance of Van Doesburg. Full of vitality and zeal for the already international movement that was called 'abstract', and most sincerely appreciative of my work, he came to ask me to collaborate in a review he intended to publish, and which he [Theo van Doesburg] was to call 'De Stijl'. I was happy with an opportunity to publish my ideas on art, which I was engaged in writing down: I saw the possibility of contacts with similar efforts.

The rectangular plane of varying dimensions and colours visibly demonstrates that internationalism does not mean chaos ruled by monotony but an ordered and clearly divided unity. In Neo-Plasticism, there are, in fact, very definite boundaries. But these boundaries are not really closed; the straight lines in rectangular opposition to one another constantly intersect, so that their rhythm continues throughout the whole work.. .These frontiers will be clearly defined but not 'closed'; there will be no customs, no work permits. 'Foreigners' will not be viewed as aliens.