Mondrian was an outspoken artist who was passionate about his work and also modern art in general.
Some of the quotes below help us understand his reasons for moving away from the early styles of his career, and what motivated him to concentrate on a signature style of abstract form and line later on.
I am only satisfied insofar as I feel 'Broadway Boogie Woogie' is a definite progress, but even about this picture I am not quite satisfied. There is still too much of the old in it.
Everything is expressed through relationship. Colour can exist only through other colours, dimension through other dimensions, position through other positions that oppose them. That is why I regard relationship as the principal thing.
To move the picture into our surroundings and give it real existence has been my ideal since I came to abstract painting.
I do not know how I shall develop, but for the present, I am continuing to work within ordinary, generally known terrain, different only because of a deep substratum, which leads those who are receptive to sense the finer regions.
If the universal is the essential, then it is the basis of all life and art. Recognizing and uniting with the universal therefore gives us the greatest aesthetic satisfaction, the greatest emotion of beauty.
Dance, theatre, etc. as art, will disappear along with the dominating 'expression' of tragedy and harmony: the movement of life itself will become harmonious.
As tradition, the female element clings to the old art and opposes anything new - precisely because each new art moves further away from the natural appearance of things.
The artist sees the tragic to such a degree that he is compelled to express the non-tragic.
Things are beautiful or ugly only in time and space. The new man's vision being liberated from these two factors, all is unified in one unique beauty.
Art is not made for anybody and is, at the same time, for everybody.
I believe it is possible that, through horizontal and vertical lines constructed with awareness, but not with calculation, led by high intuition, and brought to harmony and rhythm, these basic forms of beauty, supplemented if necessary by other direct lines or curves, can become a work of art, as strong as it is true.
I construct lines and color combinations on a flat surface, in order to express general beauty with the utmost awareness. Nature (or, that which I see) inspires me, puts me, as with any painter, in an emotional state so that an urge comes about to make something, but I want to come as close as possible to the truth and abstract everything from that, until I reach the foundation (still just an external foundation) of things.
This new plastic idea will ignore the particulars of appearance, that is to say, natural form and colour. On the contrary, it should find its expression in the abstraction of form and colour, that is to say, in the straight line and the clearly defined primary color.
The new plastic idea thus correctly represents actual aesthetic relationships. To the modern artist, it is a natural consequence of all the plastic ideas of the past. This is particularly true for painting, which is the art least bounded to contingencies. The picture can be a pure reflection of life, in its deepest essence.