The auther first defines that a theory is an interrrelated set of definitions and propositions, put forth to anticipate and explain the phenomena by dint of recognizing the relation between factors.The developmental theory, ascientific theory based on genetic methods aims to render a new organizattioin of the data and the relevant knowledge.Upon this, Piaget proviedes a co-variational relation between the subject and thing phenomena.
The auther mentions three major tasks for Piaget's theory:
1. the theory should anticipate decreasing and increasing changes of the mind as well as its processes in thinking, perception, and language.
2. The theory should study the relevant changes in time within the boundaries of behaviours and tries to explain psychological acts.
3.The theory should focus on a series of psychological transformations noted above.
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