A bricoleur of cosmologies, cities and signs, a hypnosis subject, a collaborator and a collector of art and ethnographic objects, Matt Mullican has embodied and redefined the wilder horizons of conceptual art over the course of his 40-year career. From the start, Mullican has tackled only the big themes: the self, which with some courage he has dismantled under hypnosis, performing and making art as another Matt Mullican named "That Person"; and the universe, which he has imagined as a proliferating cosmology of signs, taking form under his "Five Worlds" concept or as a city. In this bilingual volume of conversations with Koen Brams and Dirk Pultau, Mullican also proves himself an articulate, generous talker. The conversations are themed in five chapters: "Collaboration," "Cosmologies," "Hypnosis," "City" and "Collections." Across these seemingly diverse topics, what emerges as the unifying principle throughout Mullican's activities is his exemplariness as a true "cosmonaut of inner space."