"So there is nothing surprising about an artist like Pamela Rosenkranz deciding to organize her visual arts activity around the invisible: on the contrary, this is probably the only possible way of reinstating the reality of our day and age within the framework of representation. Since prehistory, art has given substance, or form, to non-visual entities — as a general rule to deities and abstract forces. With modern art, the invisible has gradually become more problematic under the aegis of the notion of immaterial, meaning within a dialectic with the object. In conceptual art, the idea thus became a “machine producing art,” as it was defined by Sol LeWitt. Yves Klein, whose ideas about monochromy are often referred to by Pamela Rosenkranz, developed his work on the immaterial on the basis of a contrast between line and color: the latter, he thought, is “free,” “like the humidity in the air,” while the line encloses and forecloses life. “Color basks in the whole just like everything that is indefinable sensibility,” he wrote, “without form or limit. This is indeed space-matter, simultaneously abstract and real.”1 Otherwise put, for the modern artist the invisible represented a sort of raw material in which to steep things with one’s personal sensibility."