EDUCATION OF THE SENSES 173
a certain point, should be able to measure the length of time for which the various stimuli held the attention.
In fact, when the child educates himself, and when the control and correction of errors is yielded to the didactic material, there remains for the teacher nothing but to observe. She must then be more of a psychologist than a teacher, and this shows the importance of a scientific preparation on the part of the teacher.
Indeed, with my methods, the teacher teaches little and observes much, and, above all, it is her function to direct the psychic activity of the children and their physiological development. For this reason I have changed the name of teacher into that of directress.
At first this name provoked many smiles, for everyone asked whom there was for this teacher to direct, since she had no assistants, and since she must leave her little scholars in liberty. But her direction is much more profound and important than that which is commonly understood, for this teacher directs the life and the soul.
Second. The education of the senses has, as its aim, the refinement of the differential perception of stimuli by means of repeated exercises.
There exists a sensory culture, which is not generally taken into consideration, but which is a factor in esthesiometry.
For example, in the mental tests which are used in France, or in a series of tests which De Sanctis has established for the diagnosis of the intellectual status, I have often seen used cubes of different sizes placed at varying distances. The child was to select the smallest and the largest, while the chronometer measured the time of reaction between the command and the execution of the act. Account was also taken of the errors. I repeat that