Materialism has returned to the forefront of humanistic speculation, as scholars rethink how to be human in the face of environmental change. Today, who counts as a historical and/or environmental agent depends largely on what one thinks a material is. This course mines the history of architecture and its allied engineering for technical and philosophical perspectives on this material turn. We alternate seminar discussions (on themes such as solidity, invisibility, aggregation, operability, wires) and workshops (where guest scientists, historians, practitioners lead us in experiments in thinking and making).