ABSTRACT
Participation in social interactions constitutes a regular and inevitable feature of the everyday experience of infants from birth on. All social interactions, irrespective of their content or the age of the participants, involve highly intricate, closely synchronized sets of behavior patterns contributed by two or more individuals. They are dialogues, verbal or nonverbal, generally characterized by impressive "smoothness" and conducted according to sets of rules that are more often than not far from explicit. Development always occurs in an interpersonal context. In some respects, this is particularly true in the earliest stages, although in the adult, too, behavior has generally a social dimension without which it would lose its most distinctive characteristic. Sociability is multifaceted. It is constituted of a great many diverse, which may have little in common with one another except for the all-important fact that they jointly define the individual’s capacity to participate in social life.
