Concavity Exercise

a detail photograph of a circular hole in a white form — Zhijian Xiong, BID 2018

three images of a curved white form made of a thin continuous plane, seen from different angles — Alex Morpurgo, BID, 2013

a white cube with circular incisions on all sides — Student Work, Author Unknown, 1980s

a black and white photograph of a complex plaster form — Author Unknown, from Interiors, June 1953

a photograph of a white cube with circular incisions on each side — Joyce Macoro, BID 2021

The concavity exercise asks students to think about erosion in natural forms and how that concavity contrasts with the convexity of the objects. Dominant, subdominant, and subordinate relationships are developed through sketching. Students are asked to be aware of the axes and not to trap the negative space, instead allowing it to flow through the object. Final designs are executed in plaster or salt blocks. The presence of the form is increased through extraction.