The second exhibition “Serial Thoughts” of the three-part series “Shades of Thought” at Metropol Kunstraum shows drawings by Bill Bollinger, Hanne Darboven, Dan Flavin, Donald Judd, Imi Knoebel, Sol Lewitt, Robert Mangold, Agnes Martin, David Rabinovitch, Fred Sandback and James Turrell as well as complementary sculptures by Judd and Sandback. The works were created between 1962 and 1992 and are dedicated in different ways to the theme of series and the concept of variation, be it in forms, time or light. Sol LeWitt, for example, focuses on the repetition of geometric forms and a precise structure; in an interview from 1967, he explains his concern as “the aesthetic concept. Dimensions, sequence of geometric units, simple systems. Spiritual playgrounds. Beauty.”