Many practices in special education for the mentally retarded have a tendency to make little account of the subjects. Subjects are considered as difflcult programme of instruction for them. But lt is true only when we accept mistaken ideas about them in present ordinary schools. We must reexamine the meanings of subjects not only in special education but also in ordinary education. It is the mecaincal cognition that human beings had a scientific cogintion of phenomena in this world for the first time. This cognition has expanded over other fields, such as physics, chemistry, biology and social sciences.
What are the factors which have brought such expansion? It is necessary to consider the viewpoints of dialectic materialism in solving those questions.
And it is impossible to systematise subjects in school education in disregard of the history of scientific cognitions.