The experience of viewing Raimund Kummer’s works is usually characterized by a conflict between what one sees and what one knows. In Kummer’s recent exhibition, six apparently heavy granite slabs piled atop one another and separated by wooden shims, prove, upon closer inspection, to be utterly fake. Treated to look like granite, they are, in fact, made of Styrofoam. Even knowing this, however, we have a hard time acknowledging the fact that these “stone slabs” are soft, light, and fragile.

A color photo mounted on top of the slabs is sandwiched between two glass panes and supported by iron girders.

Hans-Peter Feldmann’s rigorous conceptual oeuvre constitutes one of the most important efforts of the ’60s and ’70s. Hence, it is strange that his output has remained unknown or at best local. During the decade and a half (1968 to 1980) in which he was active, Feldmann produced a varied but ultimately coherent body of work that included the small-format notebooks of trivial subjects, reproduced in simple black and white, as well as the late colorations of found toys, pictures, newspaper pages, and kitschy plaster figures of ancient statues.

Producing few originals, rarely signing his pieces, and