Personality Plus talks about four key personality types. Any such system has to make generalisations, trying to find a balance between accurate portrayals and a usable number of types. The Personality Plus system allows for extensions by mixing profiles, such as describing someone as a Choleric Sanguine, rather than just Choleric or Sanguine. The system exists not simply to describe an individual's personality type, which perhaps the Myers-Briggs system does, but rather to highlight those aspects of personality which relate to interactions between people.