The Human Computer or The Whole Enchilada

On Child Egocentrism (Phillips 1969)
Phillips: 'Do you have a brother?'
Child: 'Yes.'
Phillips: 'What's his name?'
Child: 'Jim'
Phillips: 'Does Jim have a brother?'
Child:'No.'

The newest of the theories, this idea tries to do it all. It takes cognition, or overall thinking, and turns it into the most important acting force in personality.

The cognitive theory prides itself on taking into consideration all parts of the mind - thinking, knowing, memorizing, and communicating - and how they work together. In this sense, they see the mind as a computer, hardware and software interacting to form the personality. This perspective also points to general learning and how it is handled, rather than individual experience, as the main factor in shaping the personality. It sees the mind as a set-out frame waiting to be filled, rather than one shaped by experience. It is most like the behavioural view, but has humanised it by including the idea of individual thinking, personal reward, anticipated reinforcment, and social relationships. In this way it provides an empirical perspective while taking into consideration the fact that humans are... well... human.

Furthermore, the cognitive theory is the only one to clearly state that a person's behaviour is certainly shaped by surroundings, not only internal drives. What one would do surrounded by peers is completely different from what the same person would do in a strange setting.

Developed by Julian Rotter, this theory is usually used in studying child development, therefore the most well-known cognitive therapist isn't Rotter, but developmental psychologist Jean Piaget (pee-ah-zhay). He is most known for his four stages of cognitive development, and his ability to prove that children aren't just adults who know less; they actually think differently. Piaget's stages of cognitive devlopment are:

This theory is the most widely accepted, and 49% of psychologists operate under some form of this perspective.