Misidentifying Ones and Fives
Ones and Fives both correspond to Jungian thinking types–the One to the extroverted thinking type (PT, 381-82) and the Five to the introverted thinking type, or to what we suggest might better be termed the "subjective" thinking type (PT, 177-78). The main difference between them can be discerned from the fact that they are in two different Triads: Ones are an instinctive type and Fives are a thinking type. While Ones certainly do think, they are primarily people of action, and are only interested in ideas that lead to some practical result. Fives, however, are truly a mental type: they can ponder any proposition or idea and do not particularly care about its practical ramifications.
Contrary to popular notions, opinions and beliefs have their basis in the instincts, in the gut. When we assert a position ("This is absolutely the way it is!") the certainty of our view comes from our gut. If we are present enough to notice, we can feel this when we express a strong opinion. And indeed, Ones are people of strong convictions and opinions as befitting a type in the Instinctive (or Gut) Triad. Average to unhealthy Ones are entirely convinced of the rightness of their views, and respect people who hold similar strength in their convictions. They think as a way of buttressing their already established beliefs. Average to unhealthy Fives tend to get lost in a maze of uncertainty. They may develop elaborate theories or positions only to overturn them soon after. While less healthy Fives may assert provocative views, they are more interested in disturbing the certainty of others than in convincing others that they have the correct view. Unhealthy Fives may want to feel smarter than the other person, and even argue points that they do not personally agree with just to prove to themselves that they can mentally "run circles" around others. As they become less healthy, Ones become more rigid and fixed in their views about things: Fives become more uncertain, nihilistic, and afraid that they cannot arrive at any kind of meaning or truth.
Similarly, they differ most markedly in the One's emphasis on certainty and judgment and the Five's relative lack of certainty and difficulty with discernment. (While healthy Ones have excellent judgment, average Ones are merely judgmental–still, making judgments about the world around them is one of the principal ways in which their extroverted thinking manifests itself.) Judgment is not as centrally important to Fives. They want to understand how the world works on a theoretical level or create inner worlds of imagination that are interesting and amusing to them. Thus, Fives tend to be detached from the practical world and intensely involved with complex mental constructs. And while healthy Fives observe and interact with the real world around them, average Fives, as they become more deeply enthralled by their own cerebral landscapes, lose their capacity to make accurate assessments about the truth, significance, or accuracy of their ideas. They gradually care less about an idea's objective rightness than about how their ideas relate to other thoughts that arise in their minds. By contrast, Ones employ thinking so that they can relate more perfectly to the world: their focus is on making rules and procedures for the progress and improvement of themselves and their world. Average Ones are not as detached from the world, or as withdrawn as average Fives are: although they may be cool and impersonal, and somewhat overly reserved, Ones are keenly interested in applying their principles to daily life.
Thus, Ones and Fives are opposites in the way they judge and evaluate reality. Ones judge situations from idealistic standards based on what they think should be the case. Fives are constantly investigating and questioning assumptions, not to mention standards and principles. Ones are deductive, operating from principles to specific applications; Fives are inductive, operating from given data to form more sweeping theories. Both are philosophical, and love knowledge: Ones as a means of perfecting the world, Fives as a way of discovering more about the world. Ones tend to be teachers and moralists, not inventors and iconoclasts like Fives. The difference between these types can be seen by comparing George Bernard Shaw (a One) and Isaac Newton (a Five), Margaret Thatcher (a One) and Susan Sontag (a Five).