Developmental psychology has not yet shown how prosocial inborn tendencies and internalized standards of conduct on one side, and actual moral behavior on the other side, work together in early years to develop an integrated, multifaceted conscience. In fact, we expect that, from a certain point in development onward, moral core self’s mental representations will tend to be activated in moral-related behaviors — with these behaviors predicting correspondent moral declarative abilities. Main purpose of the study was to investigate developmental change in preschoolers with respect to declarative and procedural knowledge of early conscience. N=143 children were enrolled in the study (M age=4,2). We measured key elements of children’s conscience — emotion, conduct and cognition —as declared by preschoolers in response to a short played stories procedure (MSPSP), a new measure of declarative knowledge. We then assessed children’s procedural moral activation (prosocial vs. proself outcomes) in response to two dilemmatic situations (“Simulated distress” and “Animal game”). Our data confirm the hypothesis of a mild developmental trend characterized by the prominence of moral conduct over moral emotion and cognition. Of particular relevance is the emergence of a developmental turning point at around age 4, when procedural moral activation in children starts predicting the declarative feature of moral conscience. Our empirical evidence suggests that the acquisition of a “mature” theory of mind around 4 years of age seems to play an integrative role with respect to procedural and declarative sides of morality, actually binding them together.