9.2 Lifespan Theories — From Helpless Infant to Moral Adult | Psychology 2e

• Explore the fundamental question of how humans transform from infants to complex adults.
• Understand Freud's discontinuous stages and his lasting impact on developmental psychology.
• Learn Erikson's theory of lifelong development driven by social conflicts and competence.
• Examine Erikson's stages of Trust vs. Mistrust and Autonomy vs. Shame and Doubt.
• Explore Erikson's stages of Identity, Intimacy, and Integrity in adolescence and adulthood.
• Understand Piaget's theory that children think differently and use schemata to organize the world.
• Differentiate between assimilation and accommodation using a toddler's learning example.
• Learn about the sensorimotor stage and the development of object permanence.
• Identify the characteristics and limitations of pre-operational thought, including egocentrism and lack of conservation.
• Understand how children in this stage grasp conservation and apply logic to concrete objects.
• Learn about the emergence of abstract thought and hypothetical reasoning in adolescence.
• Explore cognitive growth beyond Piaget, integrating logic with emotion and the brain's physical wiring.
• Understand how culture and social interaction shape cognitive development.
• Learn Kohlberg's theory of moral reasoning stages using the Heinz dilemma.
• Distinguish between preconventional and conventional moral reasoning.
• Understand postconventional moral reasoning and the gap between reasoning and behavior.
• Learn Carol Gilligan's challenge to Kohlberg's bias and her care-focused moral framework.
• Review key developmental theories and consider the impact of digital environments on future development.
• Up next in “Psychology 2e — Full Course (OpenStax) | Intro Psychology Lectures”9.3 Stages of Development — The Ship Always Being Built | Psychology 2e

How does a helpless, babbling infant become a complex, reasoning adult? This lesson maps the grand architecture of human development through the major psychological theories covered in Section 9.2 of OpenStax Psychology 2e. From Freud's foundational claim that childhood shapes personality, to Erikson's eight lifelong psychosocial stages, Piaget's cognitive stage model, Vygotsky's sociocultural theory, and Kohlberg and Gilligan's competing frameworks of moral development — this video walks through them all with clear examples and critical analysis. In this video: • Erikson's eight psychosocial stages explained as a "video game" of boss fights — trust vs. mistrust, autonomy vs. shame, identity vs. role confusion, and integrity vs. despair • Piaget's concepts of assimilation and accommodation illustrated with the story of toddler Abdul mistaking a sheep for a dog • How object permanence (hiding a toy under a blanket) and stranger anxiety are cognitively connected in the sensorimotor stage • The preoperational stage's two key limitations — egocentrism (Kenny buying an Iron Man toy for his sister) and lack of conservation (the pizza-slicing trick) • The postformal stage and neuroconstructivism: why cognitive development continues beyond Piaget's formal operational ceiling into adulthood • Vygotsky's sociocultural theory: how language and cultural context literally shape the boundaries of a child's thought • Kohlberg's Heinz Dilemma and Gilligan's care-perspective critique — moral reasoning vs. moral behavior, and why Kohlberg's all-male dataset led to a flawed conclusion about women #OpenStax #DevelopmentalPsychology #Piaget #Erikson #Kohlberg OpenStax Content adapted from "OpenStax Psychology 2e", by OpenStax licensed under CC BY 4.0. Content based on Web Version: Apr 23, 2026. Read the textbook online https://openstax.org/details/books/psychology-2e Music first girl talking to me. by ikkun (ex. Barradeen) | https://soundcloud.com/ikkunwastaken Royalty Free Music by https://www.free-stock-music.com Creative Commons / Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0) https://creativecommons.org/licenses/by-sa/3.0/deed.en_US