18, 19, 20, 21
 The act of "carving" is easy to explain if you think of it abstractly as the process of carving a polygon into a sphere.

 The base is a trace of an octagonal prism in its pre-carved state, and the irregular four-sided drawing on the wall behind the work shows the process of defining the outline as seen from each perspective.

 In this work, the contour lines are based on 3D modeling data, but the handwork process that follows is a very conventional woodcarving methodology and serves as an example of how the work is inscribed in the material and the efficient working order of woodcarving.