The result of comparing between the numerical values of developmental age and abilitles displayed in labor indicates that we should consider some peculiar factors in guaranteeing extensive development to mentally retarded adults. Those who have different numerical values often demonstrate similar abilities in understanding the meanings of workig processes and the necessity of being on their own. It is really true that their development is not independent from conditions relating to them. Proper conditlons for the mentally retarded are made or are not, that is the question.
But there are few studies on such problems and some of them insist that those who live in institutions are unhappy, that is, institutions do not contribute to their development.
This paper is the first trial for us to study from every side the characteristics of their development and above-mentioned conditions.