Who classified intellectual development into stages of sensorymotor, preoperational and operational stages?

Who classified intellectual development into stages of sensorymotor, preoperational and operational stages?

کس نے دانشورانہ ترقی کو سینسریموٹر ، پریپریشنل اور آپریشنل مراحل کے مراحل میں درجہ بندی کیا؟
Explanation

Jean Piaget was a Swiss psychologist who theorized stages of cognitive (intellectual) development in children.

His stages include:

  1. Sensorimotor
  2. Preoperational
  3. Concrete Operational
  4. Formal Operational