Act/React, the Milwaukee Art Museum’s recent exhibition of interactive installation art, presented work by six contemporary artists: Janet Cardiff, Brian Knep, Liz Phillips, Daniel Rozin, Scott Snibbe, and Camille Utterback. While all employ some combination of customized computer software, surveillance cameras, digital video and projection, electronic photocells and circuits, microcontrollers, synthesizers, and amplifiers, the resulting artworks nonetheless conceal their technological underpinnings. Focusing on “non-technical” interactivity, which guest curator George Fifield specifies in the accompanying catalogue...