I first began using stairs in a number of pieces in the early 80s after a visit to the Yucatan to see the Mayan temples. As a multifaceted symbol, formally stairs are a way of involving the viewer, i.e. he or she climbs those stairs mentally. It is also a way of introducing a physical rhythm to a work. For me, stairs have references to instability and frustration. In Locus, I defined a space with four different wooden towers each of which has stairs of varying proportions that seem insurmountable.