The Personality Typing System for Every Personality Type

From astrology to Enneagram to ‘BuzzFeed’ quizzes, humans can’t resist categorizing themselves and others

Allegra Hobbs
Published in
9 min readJan 15, 2020


Illustrations: Blood Bros

ToTo be human is to categorize. Long before we had a BuzzFeed quiz to tell us which character from Succession we are, we slotted people into types — by the alignment of the stars under which they were born, by the portions of certain “humors” in their bodies, and by whether they are more outgoing or quiet at parties.

Now there are behavioral-science-based systems, too: One data-backed system, developed by researchers at Northwestern University, sorts people by clusters, identifying four basic types — average, reserved, self-centered, or role model — based on over a million respondents who took an intensive personality test.

Most personality typing systems are hopelessly inaccurate, so this is an effort to move that human tendency to categorize into more scientific territory, according to one of the study’s authors. “People want to know about themselves, and that’s why they like that kind of feedback,” said William Revelle, a professor of psychology at Northwestern University.

Dimensions are more accurate than rigid categories, he said, but people aren’t inclined to think along those lines. “Thinking dimensionally is hard, which is why we talk ‘tall’ and ‘short,’ not ‘That person is 6-foot-3; that person is 6-foot-1.’ It’s much simpler to say, ‘That person’s a tall person,’ and it’s laziness in some sense.”

Of course, there’s little that science and psychology can glean from whether you’re an Aquarius, an Enneagram Type 4, a Monica, or a Slytherin. But these systems of categorization are great conversation fodder at parties and on first dates — and can be a powerful tool for self-knowledge and introspection. And, put simply, it’s fun to identify yourself and others within a type. Ultimately, Revelle acknowledged, “It really is hard not to categorize. Even though the data shows you really shouldn’t.”

Here’s a brief history of the most personality typing systems, from Hippocrates to Hufflepuffs.

Hippocrates and the four humors