In this paper the term reflection is examined from the cognitive point of view: more specifically examines the constructive role it has in the formation and growth of knowledge. The optical psychogenetic work has led us to put it in connection with construction concepts and abstraction. In particular they are recalled the contributions of the last works of Jean Piaget about her division of the concept of abstraction. On the basis of these statements we have shown that the reflection is now possible to understand it as the best tool for learning from experience.
Keywords: Learning, abstraction, construction, reflection, development