Engel's In-troduction is an effective weapon in carrying out criticisms of the decadent idealistic-metaphysical viewpoints in contemporary cosmogonical researeh.
The teaching and learning of polymorphemic words is studied from the viewpoint of psychology on the basis of criticizing traditional methods of lexical learning.
According to his critique, the intentional experience presupposes the innateness of thought, and therefore cannot account for how a new way of thinking is borne from learning and experiment.