Fifty years of empirical research in personality psychology have resulted in a scientific consensus regarding the most basic dimensions of human variability. There are countless ways to differentiate one person from the next, but psychological scientists have settled on a relatively simple taxonomy, known widely as the Big Five:
Extroversion: gregariousness, social dominance, enthusiasm, reward-seeking behavior
Neuroticism: anxiety, emotional instability, depressive tendencies, negative emotions
Conscientiousness: industriousness, discipline, rule abidance, organization
Agreeableness: warmth, care for others, altruism, compassion, modesty
Openness: curiosity, unconventionality, imagination, receptivity to new ideas
Most people score near the middle on any given dimension, but some score toward one pole or the other. Research decisively shows that higher scores on extroversion are associated with greater happiness and broader social connections, higher scores on conscientiousness predict greater success in school and at work, and higher scores on agreeableness are associated with deeper relationships. By contrast, higher scores on neuroticism are always bad, having proved to be a risk factor for unhappiness, dysfunctional relationships, and mental-health problems. From adolescence through midlife, many people tend to become more conscientious and agreeable, and less neurotic, but these changes are typically slight: The Big Five personality traits are pretty stable across a person’s lifetime.
The psychologists Steven J. Rubenzer and Thomas R. Faschingbauer, in conjunction with about 120 historians and other experts, have rated all the former U.S. presidents, going back to George Washington, on all five of the trait dimensions. George W. Bush comes out as especially high on extroversion and low on openness to experience—a highly enthusiastic and outgoing social actor who tends to be incurious and intellectually rigid. Barack Obama is relatively introverted, at least for a politician, and almost preternaturally low on neuroticism—emotionally calm and dispassionate, perhaps to a fault.
Across his lifetime, Donald Trump has exhibited a trait profile that you would not expect of a U.S. president: sky-high extroversion combined with off-the-chart low agreeableness. This is my own judgment, of course, but I believe that a great majority of people who observe Trump would agree. There is nothing especially subtle about trait attributions. We are not talking here about deep, unconscious processes or clinical diagnoses. As social actors, our performances are out there for everyone to see.
