By the transition to the formal operational stage, the last stage in Piaget’s theory, the child has all the foundations of cognitive development. This allows the individual to use and create various abstract concepts. A person at this stage, starting at age 12 and continuing until full adulthood, is capable of hypothetical deductive reasoning. The child can create theories about a possible future based on current knowledge and analyze many solutions to a given situation.
According to Piaget’s theory, there are two processes by which children process incoming information. These concepts are related to the term “schema,” a category of knowledge or mental pattern for categorization. Interacting with the outside world, the child uses either assimilation or accommodation. The first method reflects using an existing scheme to analyze a new situation. The second way means rewriting the category of knowledge following the new data received.