The social return consists in the place taken by the pupils in society. This depends in part, it is clear, upon the educational return, but only in part. One could imagine a school, and there are some of the kind, which only cares about producing graduates, without thinking of what will become of them in life, even if they go to the dogs. Every class, every school, for defectives ought to aim at rendering its pupils socially useful. It is not a question of enriching their minds, but of giving them the means of working for their living. This is an important question. Upon this depends our complete and final judgment of the utility of special education. And be it understood this is not a simple question. Nothing is simple in the sphere of sociological phenomena, and one cannot get hold of an atom of truth except by inquiries bristling with difficulties of all kinds--inquiries whose rules, moreover, are not yet known, but which will certainly be known some day. It is quite necessary. In order to discover the social return of an institution, school, or hospital, there are many data to be brought together. Here are some of them. What is the number of those who are ultimately able to look after themselves? For how long a time are they able to do so? To what extent have they been assisted by what they acquired at school? And, lastly, what becomes of the failures? But whatever the social or educational return may be, it would be most important to know what would have become of similar cases who had received no such instruction, or, rather, who had been instructed or treated by different methods. A single example will show the importance of these reservations. Recently an alienist wanted to prove that all the idiots, without exception, who had been treated in his asylum had been improved. He published copious notes upon these children, which had been taken during several years by different people--the physician, resident doctor, attendant, teacher, etc. On reading these observations one learned that one child, who on admission was unable to walk, by-and-by began to do so. He had grown; he had also begun to speak, etc. In all this there was nothing surprising, and we imagine that, in spite of his optimism, the doctor, who is the author of these observations, would not pretend to credit an increase in size to his medico-pedagogical treatment. As to the rest of the development of the faculties we know nothing. It is possible that an idiot who has ceased to be dirty, or who has learned to dress himself, would have done so in any case without object-lessons. It would be necessary to understand the natural development of idiocy in order to estimate exactly the service which had been rendered by the medico-pedagogical treatment. Otherwise sceptics will suspect that three-quarters of what is claimed to be the result of treatment is really due to nature. After these preliminaries, let us now turn to our inquiry.