Gradually he pieced together a "blueprint" for normal cognitive development in children ... the toy still existed. Piaget found four major developmental stages (with many subdivisions).

However, Piaget noted that they do not yet understand concrete logic. At this point in development ... which he termed ...

Logic in the Concrete Operational Stage Piaget determined that ... is also marked by decreases in egocentrism. While children in the preceding stage of development (the preoperational stage ...