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arises from the impression which images make on the
eye, or by an effusion of visual rays from the eye, as na¬
turalists contend, it is certain that, in some way or other,
the eye is often deceived. Since, then, some images are
falsely conveyed, and others appear different from what
they really are, I think it beyond doubt, that, according
to nature and the circumstances of the place, diminutions
or additions should be made, so that no defect may be ap¬
parent. To do this, however, is the result of genius, not
the result of learning. The proportion of the symmetries
is, therefore, to be first settled, so that thereon the ne¬
cessary changes may be made with certainty. Then the
length and breadth of the plan of the work is to be set
out, and the parts thereof; after which, the proportions
are adjusted as propriety requires, so that the pleasing
arrangement may not be disturbed. The method of
effecting this I am now about to describe, and shall
begin with the court (cavæedium).