In reply to Szekely's challenge to his formulations on the development and manifestations of emotions in the infant, Spitz restates and elaborates the evidence and reasoning in support of those earlier formulations. The three-month infant reacts with a smile to the experience with the mother, in response to the 'eyes-nose-forehead configuration'. This smile indicates the capacity for positive emotion. Negative emotions, appearing in the first year of life, have a more complex history. Fear occurs in the presence of a recognized (previously experienced) threat. Anxiety is a signal by the ego warning the organism of an impending danger from within. Szekely's conflicting hypotheses, based largely on the study of animal behavior, cannot be considered valid for the human infant.