The first section is an inspiring interpretation of invention, experimentation and critical progress in aesthetics. Uses his contemporaries as examples on specific points, but does't limit the call to arms
for spiritual revolution to his particular place in art history. Just as interesting a work of religious writing as it is an essay on abstraction in art. Criticized for throwing convention out the window without offering sufficient definition of the new direction he seems to be talking about, but in retrospect I think that makes his philosophy more available to someone who reads it, say, 100 years later. The second section is pretty technical and specific to painting, but still interesting to see how he's rethinking form and color less as tools for representation and more as the vocabulary of a new kind of language.