I walk to where the water endsWang Wei (699–759)
And sit and watch as clouds arise.
Stieglitz photographed clouds from 1922 into the thirties. A symbolist aesthetic underlies these images, which became increasingly abstract equivalents of his own experiences, thoughts, and emotions. The theory of equivalence had been the subject of much discussion at Gallery 291 during the teens, and it was infused by Kandinsky's ideas, especially the belief that colors, shapes, and lines reflect the inner, often emotive "vibrations of the soul." In his cloud photographs, which he termed Equivalents, Stieglitz emphasized pure abstraction, adhering to the modern ideas of equivalence, holding that abstract forms, lines, and colors could represent corresponding inner states, emotions and ideas.