Art is higher than reality and has no direct relation to reality. To approach the spiritual in art, one will make as little use as possible of realit… - Piet Mondrian

With regard to the diagonal, too, I am in complete agreement with you [with Theo van Doesburg ]. As soon as it appears together with straight [horizontal and vertical] lines, I believe it should be condemned.. .A while back I started a thing entirely in diamonds [diamond-shape] like this [his sketch in the letter of several diamond-forms]. I have to find out if it's possible: intellectually I'm inclined to say it is. There's something to be said for the idea, because perpendicular and flat lines can be seen everywhere in nature; by using a diagonal line I would be canceling that out. But I'm inclined to say that this cannot be combined with perpendicular and flat lines or with different kinds of slanting lines.

I believe that new art must differ totally in its manifestation from art as we know it, and people may be very reluctant to accept this. It is perhaps true to say, as someone did of cubism, that 'To sum up: since art is a need to create rather than imitate, the 'cubists' rousing themselves from the sentimentality born of the picturesque aspect of some natural spectacle or other, disengage the fleeting aspects from those which are constant and absolute, and with the aid of these two elements, construct a reality equivalent to that which they see before them'. Thus it is a question of finding the true equivalence (that, offered by Cubism is still not true equivalence), and this can only be 'that which is not nature at all, and is nonetheless one with nature [like in Neo-Plasticism / De Stijl ].

It took me a long time to discover that particularities of form and natural colour evoke subjective states of feeling which obscure pure reality. The appearance of natural forms changes, but reality remains. To create pure reality plasticity, it is necessary to reduce natural forms to constant elements of form, and natural colour to primary colour. The aim is not to create other particular forms and colours, with all their limitations, but to work toward abolishing them in the interest of a larger unity.