Psychological Types: General Description of the Types, Paperback/C. G. Jung

In the book Jung categorized people into primary types of psychological function. He proposed four main functions of consciousness: Two perceiving functions: Sensation and Intuition Two judging functions: Thinking and Feeling The functions are modified by two main attitude types: extraversion and introversion. Jung theorized that the dominant function characterizes consciousness, while its opposite is repressed and characterizes unconscious behavior.