Human: Where did Carl Gustav Jung get the idea for the four-quadrant model of personality? Assistant: 
Jung was influenced by the work of Sigmund Freud, who had developed the four-quadrant model of personality. The four quadrants are introversion, extroversion, sensing, and intuition. Introversion is the tendency to focus on the inner world, while extroversion is the tendency to focus on the outer world. Sensing is the tendency to focus on the physical world, while intuition is the tendency to focus on the spiritual world.