Does a child who fails a conservation task lack logic, or lack the stage Piaget named?
Piaget’s answer was a stage: the child has not yet built the schema that makes conservation possible (Myers & DeWall, 2021; Spielman et al., 2020). Later work showed that procedure matters — a child can pass a simpler version of the same job. Development is change across the lifespan, not only childhood. Figure 8.1 lists Piaget’s stages as the intro map, then one Vygotsky term that relocates the job into social help: the zone of proximal development.
What continues after adolescence?
Adulthood and aging still count as development: cognition, social roles, and the body keep changing. Attachment begins in infancy and remains a construct in adult close relationships. Developmental Psychology will slow this down. This survey only has to stop the habit of treating development as something that ends at eighteen.
| Account | Claim about a new cognitive job |
|---|---|
| sensorimotor | Infants know through action and senses; object permanence is acquired. |
| preoperational | Symbols and language; conservation often fails. |
| concrete operational | Conservation and logical operations on concrete cases. |
| formal operational | Abstract and hypothetical reasoning become available. |
| zone of proximal development | A job the learner can do with help, not yet alone. |
Check yourself with a quick quiz
A few questions on this lesson only. Questions you miss come back later. Progress stays in this browser and is shared with the full quiz.
References
- Myers, D. G., & DeWall, C. N. (2021). Psychology (13th ed.). Worth.
- Spielman, R. M., Jenkins, W. J., & Lovett, M. D. (2020). Psychology 2e. OpenStax.
Image and media credits
- Top image. A row of shoes from a toddler's to an adult's on a shelf. It sets the scene for this lesson on development across the lifespan. Source: Created for this site with Grok Imagine (xAI), an AI image generator. License: Original image made for mattgaugerx.com.
