In this genetic tracing back of the complexities of man’s mental life to their primitive elements in the child’s consciousness, questions of peculiar interest will arise. A problem which though having a venerable antiquity is still full of meaning concerns the precise relation of the higher forms of intelligence and of sentiment to the elementary facts of the individual’s life-experience. Are we to regard all our ideas, even those of God, as woven by the mind out of its experiences, as Locke thought, or have we certain ‘innate ideas’ from the first? Locke thought he could settle this point by observing children. To-day, when the philosophic emphasis is laid not on the date of appearance of the ‘innate’ intuition, but on its originality and spontaneity, this method of interrogating the child’s mind may seem less promising. Yet if of less philosophical importance than was once supposed, it is of great psychological importance. There are certain questions, such as that of how we come to see things at a distance from us, which can be approached most advantageously by a study of infant movements. In like manner I believe the growth of a moral sentiment, of that feeling of reverence for duty to which Kant gave so eloquent an expression, can only be understood by the most painstaking observation of the mental activities of the first years. There is, however, another, and in a sense a larger, source of psychological interest in studying the processes and development of the infant mind. It was pointed out above that to the evolutional biologist the child exhibits man in his kinship to the lower sentient world. This same evolutional point of view enables the psychologist to connect the unfolding of an infant’s mind with something which has gone before, with the mental history of the race. According to this way of looking at infancy the successive phases of its mental life are a brief _resumé_ of the more important features in the slow upward progress of the species. The periods dominated successively by sense and appetite, by blind wondering and superstitious fancy, and by a calmer observation and a juster reasoning about things, these steps mark the pathway both of the child-mind and of the race-mind. This being so, the first years of a child, with their imperfect verbal expression, their crude fanciful ideas, their seizures by rage and terror, their absorption in the present moment, acquire a new and antiquarian interest. They mirror for us, in a diminished distorted reflection no doubt, the probable condition of primitive man. As Sir John Lubbock and other anthropologists have told us, the intellectual and moral resemblances between the lowest existing races of mankind and children are numerous and close. They will be illustrated again and again in the following studies.