It is Schopenhauer's theory of music which has influenced most directly the world of art. It was hailed by Wagner as a revelation, and it determined his musical development and all his æsthetic theories. Through Wagner it may be said to have revolutionised much of modern music. After reading _The World as Will and Idea_, Wagner wrote, "I must confess to having arrived at a clear understanding of my own works of art through the help of another, who has provided me with the reasoned conceptions corresponding to my intuitive principles." This philosophy contained, he said, the intellectual demonstration of the conflict of human forces, which he himself had demonstrated artistically. _Architecture_.--In Schopenhauer's arrangement of the arts, music, as we have seen, occupies the supreme place, being the highest expression in art which man can achieve. At the other end of the scale stands architecture. Its aim is to bring to greater distinctness some of the ideas which represent the lowest grades of the will, such as gravity, cohesion, rigidity, and hardness. These are the universal qualities of stone, and the simplest, most inarticulate manifestations of will. They may be called the bass notes of nature. The conflict between gravity and rigidity is the sole æsthetic material of architecture. Its problem is to make this conflict appear distinctly in a multitude of different ways. The beauty of a building lies in the obvious adaptation of every part to the stability of the whole. The position, size, and form of every part must be so {69} related to the whole, that it forms a necessary and inevitable part of an organic unity. Each arch, column, and capital must be determined by its relation to the whole building.