As author Thomas Erikson observes in Surrounded by Idiots, the subject of personality has long fascinated people of different time periods and cultures. Throughout history, thinkers have debated the concept of temperament or personality, and created systems of categorization in an effort to understand different facets of human behavior. Erikson cites Hippocrates as one of the first intellectuals to form a theory of personality. In his view, people’s temperaments were determined by their physical “humors,” which also played a large role in their physical health. Hippocrates conceived of four humors, and therefore believed that there were four corresponding personality types. For instance, a “choleric” person’s behavior would be influenced by their abundance of yellow bile, causing them to be “fiery and temperamental” (Location 3336).

In modern times, psychologists and social scientists have continued to study personality through more modern means. One popular approach to personality is the Meyers-Briggs Type Indicator, which was developed by Isabel Briggs Meyer and Katharine Briggs. The methodology is based on psychologist C. G. Jung’s theories on “psychological types” which he described in a book of the same name. According to Jung, there are 16 possible personality types, based on different combinations of four major traits: Extroversion or Introversion, Sensing or Feeling, Thinking or Intuiting, and Judging or Perceiving.