Erikson, Piaget & Psychology Theories & Concepts Explained

Generativity vs Stagnation: What Erikson’s Stage 7 Looks Like at 45

Generativity vs stagnation is the seventh stage of Erik Erikson’s psychosocial theory, a midlife conflict between investing in the next generation and turning inward. Picture two 45-year-olds with similar jobs and similar mortgages. One spends Thursday nights coaching a robotics team and lights up talking about her students. The other feels strangely flat, like life peaked ten years ago and...

Conservation in Psychology: Piaget’s Tasks Kids Get Wrong

Conservation in psychology is the understanding that an amount stays the same when only its appearance changes. Pour juice into a taller glass, roll clay into a snake, or spread out a row of coins, and nothing has been added or taken away. Jean Piaget found that most children under about seven insist otherwise, and they say it with complete...

Social Identity Theory: What Tajfel & Turner Said in 1979

Social identity theory, developed by Henri Tajfel and John Turner in 1979, proposes that part of who you are comes from the groups you belong to, and that people favor their own groups to protect a positive sense of self. That sounds obvious until you see the evidence behind it. In the early 1970s, teenage boys sorted into groups by...

Vygotsky’s Sociocultural Theory: ZPD, Scaffolding, Play & How Culture Shapes Learning

Vygotsky’s sociocultural theory, often called Vygotsky’s theory of cognitive development, proposes that learning is fundamentally social. Children build knowledge through interaction with others, guided by more skilled partners and the tools their culture provides. Its best-known ideas are the zone of proximal development, scaffolding, and the role of language in thought. But a few things students “know” about this theory...

Ecological Theory of Aging: Bronfenbrenner vs Lawton Explained

The ecological theory of aging holds that how well someone ages depends on the fit between that person and their surroundings, not on health or age alone. Picture two 80-year-old women who break a hip in the same week. Six weeks later, one is back at her Thursday book club. The other hasn’t left her apartment since the hospital sent...

Between Subjects vs Within Subjects: Why People Rated 9 Bigger Than 221

Imagine asking one group of people how big the number 9 is, and a different group how big 221 is. In a real study, the group judging 9 gave it the higher rating (Birnbaum, 1999). Nobody forgot how numbers work. The result came from the experimental design. The choice between subjects vs within subjects decides whether each participant experiences one...