1.2 Stages of Human Development

The developmental ladder (the exam's map): infancy (0–2: attachment's foundation); earlychildhood (2–6: the symbolic world, the first rules); middle childhood (6–11: school-age — concrete thinking, rule-morality, the peer's arrival); adolescence (11–18: puberty's transformation — abstract thought's dawn, identity's work, the peer's primacy); emerging adulthood (18–25: the prefrontal completion — planning, restraint, consequence). The psychology's anchors (names only): Piaget's cognitive stages (concrete → formal operations), Kohlberg's moral ladder (pre- conventional → conventional → post-conventional), Erikson's identity stages, and the modern adolescent-brain science (the reward system running ahead of the control system into the mid- twenties).