Pa of mind which is working on reality principle is
Sigmund Freud gave Structural theory of mind. it is the cornerstone of ego psychology. Three provinces are- Id- reservoir of unorganised instinctual drives. It is more concerned with basic instincts. Ego- it is the executive organ of the psyche, controls motility, perception, contact with reality and through defense mechanisms available to it, the delay and modulation of drive expression. Superego- establishes and maintains an individual's moral conscience on the basis of a complex system of ideals and values internalised from parents. Ref: synopsis of Psychiatry, 11e, pg 159.
Ego
Id
Ego-ideal
Super ego
Cognitive development and defence mechanism