In the group painting "seawall and sea", all traces of curves have disappeared, and straight lines dominate the picture. Although the formal factors show their vitality more and more, mondriaan is not satisfied. He later wrote, "Looking at the sea, the sky and the stars, I show them through a large number of crosses. I was deeply moved by the greatness of nature. I try to express vastness, tranquility, harmony and unity ... However, I feel like an impressionist painter, expressing a special feeling rather than a real reality. " ?

His so-called "true truth" is the "pure truth" hidden under the natural appearance. For mondriaan, who is keen on theism, everything in nature, whether it is scenery, trees or architecture, has its potential "pure reality". Although natural objects are different in appearance, their essence is the same. The painter's task is to reveal the pure reality and universality hidden in his paintings. ?

With the association with the Dutch mathematician and philosopher Su En Meikel, his thoughts became more and more mature.

19 16, mondriaan met Su En mekel by chance in laren. Since then, the two have often met and exchanged enthusiasm. Suen Meikel is an theist and once a Catholic priest. He put forward a new Plato's philosophy, which is called "empirical mysticism" or "plastic mathematics". For these two seemingly unrelated terms, he explained: "From the creator's point of view, plastic mathematics means real orderly thinking." Empirical mysticism points out a creative principle: "We are now studying how to transform our imaginary reality into a structure that can be controlled by reason, so as to rediscover these same structures in a' definite' natural reality and gain insight into nature with the help of plastic vision." Suen Meikel said that his new philosophical system enabled people to "go deep into nature through meditation and see through the hidden inner structure of reality." He said, "Although nature is lively and willful in change, it basically always performs its tasks with absolute regularity, that is to say, it works with the regularity of modeling. Regarding the law of modeling, he pointed out that there are pairs of opposing elements in nature, such as positive and negative, male and female, space and time, darkness and light. Can be compressed into horizontal and vertical lines by simplification. In his view, these two lines are connected with the power of the universe-the vertical line is related to the irradiation of the sun, and the horizontal line is related to the constant movement of the earth around the sun. Suen Meikel has a similar view on color. He believes that there are only three primary colors, and they are all symbolic-yellow symbolizes the radiant movement of the sun, blue symbolizes the infinite extension of the sky, and red is a neutral and collocation color, which is a "whisper of yellow and blue at dawn."

The thought of Suen Mekel is an important inspiration to mondriaan. It provides something that all other pioneers of abstract art have not found, that is, a way to give a painting spiritual meaning, which has nothing to do with the outside world. The symbolism of abstract works makes it very different from decorative patterns, which is also the inherent feature of works. According to Su En Meikel, this is because the spirit can be "best expressed through pure modeling factors, such as primary colors, and the contrast between darkness and light, horizontal and vertical."

Mondriaan spent a year or two applying these ideas to his own painting experiments and created a unique geometric abstract painting language. He ruled out all curves and used straight lines. He put colored rectangles on a white background and framed them in a linear grid covering the whole picture. At 192 1, he finally developed a simplified and refined geometric abstract schema: a grid structure of three primary colors, three achromatic colors (black, white and gray) and "horizontal lines-vertical lines". Through this model, mondriaan seeks the absolute balance between visual elements. Every element of his works has been carefully scrutinized and carefully arranged in the right place, just right.

This painting (red, yellow and blue) was painted on 1930, which is one of the representative works of mondriaan's geometric abstract style. We can see that the thick black line controls seven rectangles of different sizes, forming a very simple structure. The picture is mainly bright red in the upper right, which is not only huge in area, but also extremely saturated in chromaticity. A small piece of blue on the lower left and a little yellow on the lower right effectively match four pieces of gray and white, firmly controlling the balance of red squares on the screen. Here, there are no other colors except the three primary colors; There are no other lines except vertical lines and horizontal lines; There are no other shapes except right angles and squares. Clever division and combination make the plane abstraction into a rhythmic dynamic picture, thus realizing his geometric abstraction principle. "With the basic elements of painting: straight lines and right angles (horizontal and vertical), three primary colors (red, yellow and blue) and three non-pigments (white, gray and black), these limited pattern meanings and abstractions are combined with each other, symbolizing the power of nature and nature itself."

Mondriaan called his new painting "New Modelism" and wrote a series of articles to explain this term. He borrowed the term from Su En Meikel. In his view, new sculpture is superior to romanticism and expressionism, because it makes art transcend individuals. mondriaan's main purpose is to destroy himself in art. What art expresses should be the artist's unconscious reaction to the world in which he lives, and it is the force of the universe that exists in all our hearts. The purpose of the new plastic arts is to achieve harmony and balance; Losing harmony and balance will lead to tragedy, which is a "curse to mankind". Therefore, mondriaan's art will inevitably show a utopian color, as he said: "The new way of watching … just as it leads to new art, it will inevitably lead to a new society; A society with two kinds of equivalent elements (material and spirit), a harmonious and balanced society. "His paintings provide a perfect example of harmony in the universe. They are balanced, orderly and optimistic, showing a restless, quiet and clear humanity. " In the dynamic abstract reality, "mondriaan said," the new development of human beings has gone beyond the scope of nostalgia, joy, ecstasy, sadness, fear and other feelings: beauty makes feelings eternal, and in this feeling, these feelings are pure and clear. "