Now for the educational consequences of the preceding theory. If the backwardness is only a slowness of development, it will suffice to apply to the backward the same methods as to the normal. One will make them follow the same course of study and go just as far as possible. Every defective must work towards the primary school certificate. To attain that end, he ought to pass through seven regular stages, one each year. The teacher of defectives cannot hope that he will bring his pupils to the last stage. He will stop half-way. One day, at the agricultural colony of Vaucluse, when some foreign doctors were visiting the establishment, the teacher showing his class to the visitors remarked with naïve pride: "Our pupils follow step by step the curriculum of the primary school." A second and totally different theory is tenable, and this one appears to us to be much nearer the truth. It is that a defective child does not resemble in any way a normal one whose development has been retarded or arrested. He is inferior, not in degree, but in kind. The retardation of his development has not been uniform. Obstructed in one direction, his development has progressed in others. To some extent he has cultivated substitutes for what is lacking. Consequently such a child is not strictly comparable to a normal child younger than himself. So far as certain faculties are concerned, he remains at the level of a younger child; but in respect to others, he is on a level with normal children of his own age. An unequal and imperfect development is consequently his specific characteristic. These inequalities of development may vary to any degree in different subjects. They always produce a want of equilibrium, and this want is the differentiating attribute of the defective child. But to draw a faithful picture we must add yet other traits. According to general opinion, mental deficiency is a disease, and although the idea of disease is very vague, we are inclined to fall in with this general opinion. In the first place, we frequently find in such children defects of speech. Besides, in studying their mental condition more closely, one finds in some cases peculiarities of understanding, reasoning, imagining, difficult to define, but which do not appear to have their equivalent in younger normal children, and which therefore do not result from simple retardation of development. Here is a boy, twelve years of ago, who tries to answer our questions, and succeeds pretty well; but hardly has he finished his answer when he deserts the subject altogether and begins to talk a lot of nonsense. This want of coordination in thought constitutes a special defect, and not a retardation of development. Possibly one would not find analogous features in other backward children, who tend rather to be laconic; but it is also possible that a careful analysis of their mental state might reveal in them other mental symptoms, and, indeed, such are very