The most influential figure in the study of congnitive development

Jean Piaget

Explanation:

Jean Piaget was a Swiss psychologist who did influential work in the field of cognitive psychology and child development.

Piaget’s famous theory of cognitive development explains the phases and nature of human development during the formation years from 0 to 11. It explains how children acquire knowledge, how they perceive the world, and how they construct and use intelligence during the development.

The theory poses four stages:

Sensorimotor Stage - lasts until year 2 – realizing that objects are there even when the person’s not directly looking at it.Preoperational stage - from 2 to 7 years – ability to comprehend that word or object can mean something different; symbolic thinking.Concrete operational stage – from 7 to 11 years – child starts to have logical and operational thoughts, working things out in head rather than in the real world.Formal operational stage – from 11 and above – development of the abstract thoughts and concepts.

If he tries to grape you then get a grape and grape him back