ABSTRACT
The infant at birth is essentially nothing more than a biological organism. With the exception of possible reflex conditioning in the uterus, behavioral events do not take place prior to birth. This means that behaviors evolve during the course of the postnatal life of the individual. Since that is the case, the period immediately following birth is a time of transition. The newborn infant begins to get into contact with the many objects around him, and happenings that have the distinctly psychological characteristics of differentiation, integration, variability, modifiability, delayability, and inhibition develop. That is to say, such action as discriminating milk bottles from rattles and the crib begins to develop soon. Reaching for a milk bottle is attempted first one way, then another, and so on until the act is accomplished. Likes and dislikes develop so that the cod-liver oil, which at first may be poured “down the hatch” with no more difficulty than milk, is later discriminated and rejected. Gradually, toilet habits are evolved that may permit delay and inhibition. By this stage, the infant is well launched on his psychological career, but not without a complex and very gradual evolution. The beginnings of that career are much simpler.
