When considering intelligence, Piaget focuses on the mental processes thatoccur, rather than on the actual measure of the intellect. He uses four areasto define intelligence. These areas are: a biological approach to looking at intelligence, the succession of the stages, knowledge, and intellectualcompetence.

Piaget's biological approach, or biological adaption, focuses on thephysical and mental aspects of our bodies. This includes our reflexes whichoccur when certain stimuli trigger an instinctive response. He also discusseshow we adapt to certain situations using assimilation and accomodation. Assimilation occurs when new information is introduced to a person. The personbegins to integrate the new information into existing files, or "schema". Accomodation occurs when the person reorganizes schema to accomodatethemselves with the environment.

The succession of stages involves the movement through four stages thatPiaget has set and defined. Children must move through these stages duringtheir childhood. These include Sensorimotor, Preoperational, Concreteoperational, and Formal operational. Stage movement is an important factor ofPiaget's definition of intelligence, because Piaget states there are a specificset of criteria that must be met and mastered at each stage. In order to movefrom the first stage to the next, the child must master that specific set ofcriteria.

To define Intellectual Competence, Piaget focuses on the highest level offunctioning that can occur at a specific stage. Although Piaget has approximateages assigned to stages, a child's competence is only measured by what stagethey are in, not by age. If the child can only perform tasks that are at thepreoperational stage, that is the highest level the child is at regardless ofage.