  While Buber most famously understood the I-Thou relationship as one based on immediacy, he always steeped his thought in the power of mediating images and other plastic forms as the material stuff of inter-subjective relationship. In the essay "Man and his Image-Work," Buber set out to understand something about the formation of images in relation to the world, the world encompassed by art, faith, love, and philosophy. Buber postulated three levels of world formation. The first two levels are the familiar Kantian concepts of a noumenal “x” world and a phenomenal sense-world of form, comprising the world as shaped by and in images and concepts. Buber’s conception of the third level, what he calls the world of perfect form, derives from the mystical tradition. This paradoxical level of world formation is expressed in terms of perfected form-relations. In art, faith, and philosophy, the human image-work emerges out of relational encounters between persons and an independent "world" that exists on its own, but is not imaginable. 