In the early 1960s Rauschenberg began his long experimentation with the lithographic process. Never hindered by tradition, he was wildly inventive in his use of disparate methods and processes. The result is that many of his prints read as collages, with overlapping, transparent areas creating a shifting, fluid space.

In 1967 Rauschenberg took these ideas even further in a series of images entitled Booster and 7 Studies. Booster is made up of an X-ray self-portrait laid over with a time chart of 1967, revealing the artist as Inner Man, an idea he would use again the next year in his Autobiography. To this he adds other simple images and further enhances these with blue, red, and black. We are left with the ghostlike figure of the artist offering himself as a memento mori, a reminder of the temporality of life.