Piet Mondrian’s “The Determinate and the Indeterminate (Supplement)” (1918)
Translated from the Dutch by Hans L.C. Jaffé.
In De Stijl. (H.N. Abrams. New York:1971).
• • •
The determinate is positive for us, absolute, insofar as we can establish it objectively. We can speak objectively only of the determinate — which is universal, the universal. Subjectively we know diverse determinations, all of which are more or less individual.
If the universal — outside of time — is the determinate, then the individual, in and through which the universal appears in time, must be indeterminate and so must be our vision of it.
The indeterminate has the appearance — in time — of being determinate; the determinate — in time — of being indeterminate. We always more or less subjectivize the one determined; and for us this subjectivization is the determined. We perceive — in time — the one determined with varying degrees of clarity, and each degree is — in time — determinate for us. As the individual in us matures, and the universal in us predominates, our various individual determinations grow towards the one determined.
Each individual determination — in time — is neither more nor less valuable than another: each individual determination is to us the true one — for the time being. That is why each subsequent individual determination annihilates the previous one, and the degree of clarity with which — in time — we perceive the one determined is not arbitrary: what seems determinate to us varies with the time.
In individual vision, the (one) determined appears as vague, and the indeterminate as real. In time, the (one) determined is abstract: the indeterminate, concrete. Objectively seen — as far as this is possible — in time — the (one) determined is abstract-real.
Depending upon the character of our consciousness we see either the objective or the subjective as the determinate, the universal or the individual  the abstract or the concrete. Thus our life and our art depend upon our idea of the determinate.
The determinate — in general — demands determination and clarity, it must be clearly expressed if it is actually to be manifested as the determinate. In keeping with this requirement, art is expressed with greater or lesser clarity either through the (one) determined, or by whatever means it manifests itself.
In art, the relatively determinate (that is, the greater or lesser determination in which the (one) determined finds expression) must be clearly expressed plastically. Every age has clearly expressed its (relative) determination, and thus, more or less, the (one) determined. This is the power of art. All art has striven for clear plastic expression of the one determined: within its unclearness some degree of determination was nevertheless expressed.
If it is established by plastic expression of the determinate (the concrete) it had to find concrete plastic manifestation. It is manifested as the immutable and this immutability is equilibrated relationship.
Whereas the indeterminate (concrete) is manifested through corporeality; the (one) determined is plastically expressed as equilibrated relationship through position, dimension and value of color and plane (line).
Because equilibrated relationship is capable of finding actual visual plastic expression (although veiled), we can experience the deepest aesthetic emotion; it is the plastic, the bringing to determination of this relationship, that makes all art, art.
Naturalistic painting, therefore, can express things either in their clarity or in their vagueness; the essential is that it bring equilibrated relationship to determination. Thus the vagueness of Thijs Maris is no longer mere vagueness: he represents things vaguely, but their vagueness shows a certain degree of determinateness. Similarly, in Jan Stem, the representation of objects is not simply plastic expression of their visual appearance: he gives their corporeality a certain degree of determinateness.
In art — unconsciously or consciously — the determinate (i.e., that which is plastically determinate) is the objectively determinate; it is always the plastic expression of relationship that matters, not the representation of things.
The emotion of beauty is strong to the degree that relationship is plastically expressed determinately; and it is profound to the degree that its plastic expression is equilibrated.
In the course of its culture, painting carried this truth to its most  extreme consequence: it has finally achieved the plastic expression of pure relationship. Pure relationship in painting does not mean relationship and nothing else, for such an expression would not be ‘art.’ The plastic expression of relationship must fulfill every aesthetic demand if it is really to be ‘art’ and is to awaken our aesthetic impulse.
Having evolved to the point of plastically expressing aesthetic relationship purely (in the above sense) painting is ready to merge with architecture. Since ancient times architecture — by its very nature (the mathematical-aesthetic expression of relationships) — far surpassed its sister arts. Although it did not always consciously express this, and although its forms were always the outcome of necessity and practical demands, it went far beyond the naturalism of painting and sculpture.
Up to the present moment, sculpture has known no more than a tensing of its form (Archipenko). It was painting (Neoplasticism) that brought the expression of pure relationship to the forefront.
This does not make Neoplastic painting merely accessory to architecture: for it is not constructional like architecture. Structural without being constructional, and free in its ability to express expansion, Neoplasticism is the most equilibrated plastic of pure relationship. Architecture always presupposes enclosure: the building stands out as a thing against space (the play of masses destroys this to some extent). Moreover, being constructional in character, and tied to the demands of its materials, architecture cannot maintain as consistently as painting the constantly self-annihilating oppositions of position, dimension and color (value).
If the determinate demands determination, then the plastic expression of relationship in art must be carried to determination. This is achieved in painting by determining color itself as well as the color planes, this consists in counteracting the blending of colors by establishing boundaries of one kind or another — by opposing plane (value), or by line. Line is actually to be seen as the determination of (color) planes, and is therefore of such great significance in all painting. Nevertheless, the plastic is created by planes; and Cézanne could say that painting consists solely of oppositions of color. Plastic can nevertheless also be seen from the standpoint of line: planes in sharper opposition form lines. Naturalistic painting thus arrives at the concept of ‘form,’ and (with Gauguin and others) we can say of determinate color that from creation is the essence of painting. Form, in this sense, determines color: the more tense the form, the more determinate the color.
If form is expressed through line, then the most tense line will determine color most strongly; line that has reached straightness will determine color to the maximum. By consistently executing color determination, leave behind the capricious and the naturalistic.
Accentuating the plastic of relationships led to the exaggeration of the plastic expression of relationships, to abstraction from the natural (Pointillism, Divisionism, Expressionism, Cubism), and finally to the plastic of pure relationship (Neoplasticism).
If we see the plastic of pure relationship gradually developed in the successive schools of naturalistic painting, we can also trace its evolution in the development of the founders of Neoplasticism. They strove to free themselves from the indeterminate (the visual appearance of things) and to achieve a pure plastic of the determinate (equilibrated relationship). While still expressing the indeterminate, they were drawn to those aspects of nature in which the determinate (equilibrated relationship) appears determinately — where relationship is veiled — and they exaggerated these (visual) relationships. Was it by chance that they found a most appropriate subject-matter through which to express their feeling for determinate relationship in an un-forshortened (non-perspective) view of a farmhouse, with its mathematical articulation of planes (its large doors and groups of windows) and its primary (basic) colors?
Was it by chance that they were attracted to straightness, and — to the chagrin of habitual vision — dared to represent a wood simply by its vertical tree trunks? Was it surprising that, once they had abstracted these trunks to lines or planes, they spontaneously came to express the horizontal — hardly visible in nature — thus creating equilibrium with the vertical? Or, that in a rhythmic linear composition of the predominantly horizontal sea, they again expressed the — unseen — vertical in appropriate opposition? Did they do more than exaggerate what all painting has always done? Again, was it by chance that they were more deeply moved by the leafless tree with its strong articulation of line or plane, than by the tree in leaf where relationship is blurred? And is it surprising that in the course of their work they abstracted natural appearance more and more, so as to express relationship more and more explicitly? And that the ensuing composition was more mathematical than naturalistic? Was it, finally, by chance, that after abstracting all that was capricious, they abstracted curvature completely, thus achieving the most constant, the most determinate plastic expression of equilibrated relationship — composition in rectangular planes?…
 Art had to free its plastic expression of the indeterminate (the natural) in order to achieve pure plastic expression of the determinate. This was done by Neoplasticism, passing through Cubism. This is intuitively seen and felt by the sensitive observer: it becomes clear to him through logical thinking. It becomes convincing in practice, whenever one compares Neoplastic with other painting.
Comparison is the standard which every artist consciously or unconsciously uses: it shows him how to express (his) truth as determinately as possible. He compares each new work with a previous one, in his own production or in that of others; he compares it with nature as well as with art. To compare is to exercise one’s vision of relationships; one is brought to see and compare basic oppositions: the individual and the universal. From a clearer and clearer perception of their relationship, a purer and purer mode of expression emerges. And so Neoplasticism logically arose.
[From De Stijl, Vol. II, No. 2, pp. 14-29]