How does human knowledge develop?
Here is the question to which the Swiss psychologist Jean Piaget devoted all his life. His work, spread out over nearly sixty years, provided the foundations of the vast field of research of the genetic epistemology that seeks to understand how our ways of thinking throughout our life.
Formed in biology and philosophy, Piaget takes as a starting point the concepts of these two disciplines to study the development of the young children, ideal ground to observe a thought constitute itself. It thus arrives very early at the conclusion that the cognitive development is the fruit of complex interactions between the maturation of the nervous system and the language, and that this maturation depends on the social and physical interactions with the world that surrounds us.
For Piaget, it is while acting on its environment that the child builds his first reasoning. These cognitive development structures (Piaget also speaks about designs of thought), at the beginning completely different from those of the adult, are interiorized gradually to become increasingly abstract.
The Piaget theory of the development distinguishes four primary cognitive structures which correspond to as many stages of development, which are subdivided then in distinct periods where particular cognitive capacities emerge.
The First Stage of Cognitive Development
The first stage, which extends from the birth to approximately 2 years, is the sensorimotor stage. During this period, the contact of the child with the world that surrounds him depends entirely on the movements that he makes and of the feelings he has. Each new object is brewed, launched, put in the mouth to gradually understand the characteristics by tests and errors. It is in the middle of this stage, towards the end of his first year that the child seizes the concept of permanence of the object, i.e. the fact that the objects continue to exist when they leave his field of vision.
The Second Stage of Cognitive Development
The second stage is that of the preoperational period which begins around 2 years and finishes around 6 – 7 years. During this period, which is characterized inter alia by the advent of the language, the child becomes able to think in symbolic system term, to represent things starting from words or symbols. The child seizes also concepts of quantity, of space as well as the distinction between past and future. But he remains much directed towards the present and the concrete physical situations, having difficulty in handling abstract concepts. His thought is also very egocentric in the sense that he often assumes that others see the situations from his point of view.
The Third Stage of Cognitive Development
Between 6 – 7 years and 11-12 years, it is the stage of the concrete operational period. With the experiment of the world, which accumulates in him, the child becomes able to consider events that occur apart from his own life. He also starts to conceptualize and create logical reasoning that, however, still requires a direct relation with the concrete one. A certain degree of abstraction also allows to approach disciplines like mathematics where it becomes possible for the child to resolve problems with numbers, to coordinate operations in the direction of the reversibility, but always about observable phenomena. To resolve problems with several variables by analyzing them in a systematic way remains exceptional at this stage.
The Fourth Stage of Cognitive Development
Finally, from 11-12 years what is been developed is what Piaget called the formal operational stage. The new capacities of this stage, like making hypothetic-deductive reasoning and establishing abstract relations, are generally mastered around the age of 15 years. At the end of this stage, the teenager can thus, as the adult, use a formal and abstract logic. He can also begin thinking about probability and about moral questions like justice.