This course of Lectures is intended to treat of Natural foliage,
leaving Artificial foliage to be dealt with at another opportunity. It
is not Historical. The History of the Decorative treatment of Natural
foliage, showing its evolution in the past, is a large and interesting
theme; but, unless this were accompanied by critical remarks based on
given principles, the method might be barren of results. Tradition is
not to be undervalued; but the student should be led to Tradition
through Principles.

It is further intended more especially to apply to the æsthetic use.
When natural foliage is used Æsthetically (i.e., decoratively), then
the Shape of the surface should govern the Mass shape of the foliage,
and there should be Parallelism between them (see § 29). When used
Didactically (i.e., symbolically), then the foliage may be treated
more freely.


§ 4.--THE FOUR TREATMENTS.

There are, broadly speaking, four methods of treating Natural foliage.
These may be arranged in a Chart, according to their relation to the
two poles of Art and Science; from Realism (which is all Art and no
Science) to the "Botanical Analysis" method (in which is a little
Science but no Art), thus:

The first two of these methods are Artistic and legitimate: the others
are inartistic and misleading. Before treating of the artistic methods
it will be well to clear the ground by dismissing the others.