t often the starting-point is an idea composed of
a group of centrally aroused sensations due to simultaneous
excitation of a group
This would probably
in every case he in large part the result of association by contiguity in terms of the older classification, although
there might be some part played by the immediate
excitation of the separatefP pby an external stimulus. Starting
from this given mass of central elements, all change comes
from the fact that some of the elements disappear and are
replaced by others through a second series of associations
by contiguity. The parts of the original idea which remain
serve as the excitants for the new elements which arise.
The nature of the process is exactly like that by which
the elements of the first idea were excited, and no new
process comes in. These successive a