In his analysis of Perception, Dr. Ward distinguishes (i) Assimilation or Recognition, (ii) Localization or Spatial Fixation, and (iii) Objective Reference, or Intuition of Things. Of these, the first, Assimilation, has already been taken up in Chapter IV, and we have seen that, according to Dr. Ward, it involves Retention and Differentiation, though in itself there is no active comparison, and we have seen that Froebel also spoke of the earliest impressions as “almost imperceptible, but _fixed_ by repetition and by change,”[43] and of a “perception of sequence” involving “dim” or “unconscious comparison.” Of the second process Dr. Ward writes: “To treat of the localization of impressions is really to give an account of the steps by which the psychological individual comes to a knowledge of space,” and he goes on to say that psychologists may have been too apt to examine “the conception of space and not our concrete space perceptions.” Now Froebel did consider concrete space perception, and with a certain amount of care. That he saw its importance is clear from the fact that in discussing his “means of employment” he says: “They will cover the whole ground of training in sense perception but _will begin with the observation of space and the knowledge that comes from that, since the child first feels and finds himself in space and finds others occupying space around him_. They are to go on by development of limbs and senses and by means of language to understand Nature in all directions, so that finally man _who at first could find himself only in space and by means of space_, may learn to know himself as an existent, feeling, thinking, intelligent, rational being, and as such to try to live.”--_P., p. 19._ And although Froebel may not fully have realized that, as Dr. Ward puts it: “The infant’s earliest lessons in spatial perception are in exploring his limbs,” still we do find him writing from Blankenburg, in a letter accompanying the first sketch of his Nursery Songs: