In analyzing Piaget's answer to Vygotsky's critics, in the present study we tried to emphasize the basic theoretical convergences and divergences appointed by the first author in relation to the second. With this in mind, as our first step, we analyzed Piaget's explanations about the reality of the psychological phenomenon of the linguistic and cognitive egocentrism; as our second step, we analyzed the relations between scientific concepts and which are spontaneously developed in the children. As our third step, we analyzed Piaget's different position about the mechanisms which explain the knowledge progress and development. We concluded that in Piaget's answer to Vygotsky there is a clear difference of his theoretical system.
Piaget; Vygotsky; Cognitive Development; Genetic Psychology; Thought Development