Selected Bibliography Architecture - Form Space and Order | Page 69

SU BTR ACTIVE FO RM

We search for regularity and continuity in the forms we see within
our field of vision. If any of the primary solids is partially hidden
from our view, we tend to complete its form and visualize it as if it
were whole because the mind fills in what the eyes do not see. In a
similar manner, when regular forms have fragments missing from
their volumes, they retain their formal identities if we perceive
them as incomplete wholes. We refer to these mutilated forms as
subtractive forms.

Because they are easily recognizable, simple geometric forms,
such as the primary solids, adapt readily to subtractive treatment.
These forms will retain their formal identities if portions of their
volumes are removed without deteriorating their edges, corners, and
overall profile.

Ambiguity regarding the original identity of a form will result if the
portion removed from its volume erodes its edges and drastically
alters its profile.

In the series of figures below, at what point does the square shape
with a corner portion removed become an L- shaped configuration of
two rectangular planes?

54 / A R C H I TE C TU R E : F O R M , S PA C E , & O R D E R