Where Do the Words Choleric, Sanguine, Phlegmatic, and Melancholic Come From?

The four words we use today to describe a temperament (choleric, sanguine, phlegmatic, melancholic) come literally from the four bodily fluids ancient medicine used to explain human health.

Hippocrates and the medicine of the four humors

Hippocrates, considered the father of medicine, lived four centuries before Christ and stood out from other physicians of his time for one very specific reason: he didn’t believe disease came from supernatural causes or divine punishment, but from the body’s own nature. According to what business author Thomas Erikson recounts in Surrounded by Idiots (2014), Hippocrates held that good health depended on the balance between four bodily humors, or fluids: blood, yellow bile, black bile, and phlegm. When the body vomited, coughed, or sweated, according to this theory, it was simply trying to get rid of an excess of one of those four fluids.

Out of that came an idea that outlived the medical theory itself by a long way: that a person’s temperament (their natural way of reacting, their baseline character) depended on which humor dominated their body. It wasn’t a poetic metaphor, it was, literally, anatomy applied to personality.

The real etymology, word by word

Each of the four classical temperaments still carries, in its own name, a direct trace of the humor that gave rise to it:

• Choleric, from the Greek khole (yellow bile): describes, in this ancient classification, a fiery, temperamental person, able to intimidate the people around them with their intense way of reacting. The word literally names someone “ruled by yellow bile.”
• Sanguine, from the Latin sanguis (blood): describes a creative, optimistic, easygoing person with a light, contagious manner, whose character, according to this root, is governed by blood itself.
• Phlegmatic, from phlegm, the thick mucus that gives the temperament its name: describes a slow, unhurried person in their movements, with a calm that other temperaments can mistake for indifference.
• Melancholic, from the Greek melaina khole (black bile), the humor ancient theory placed in the spleen: describes a person prone to pessimism and sadness, the mirror opposite of sanguine optimism.

Four words we use today almost without a thought for their literal origin, and that for more than two thousand years were the dominant scientific explanation for why people are so different from one another.

An unexpected parallel: the four Aztec elements

Erikson points out, in the same book, a detail that stands out for how far apart it is in both geography and culture: the Aztecs, the Mesoamerican people who ruled central Mexico between the fourteenth and sixteenth centuries, used a strikingly similar temperament-classification system based on four elements: fire, air, earth, and water.

“Fire” people were explosive, almost warrior-like, with a natural pull toward leadership. “Air” people were just as decisive but far lighter and more captivating in how they moved through the world. “Earth” people worked for the community, steady and focused on building something lasting. “Water” people observed quietly, calm as long as they weren’t provoked, capable of sweeping away everything in their path if they overflowed.

There’s no documented historical connection between Hippocrates’ Greece and pre-Hispanic Aztec Mexico: two civilizations that never crossed paths. Erikson acknowledges there’s no way to know for certain whether the Aztecs arrived at this classification entirely on their own, but there is material evidence that they used it: they left carvings that represent exactly this same four-way division of temperament.

Two cultures separated by thousands of miles, with no contact between them whatsoever, each landed, on its own, on the same number of categories: four, not three, not five. Coincidence or not, it’s the same number still alive today in any four-color behavioral test.

From humor to color: the line that runs to today

The underlying idea (four broad ways of reacting to the world, no more, no fewer) outlived the collapse of the medical theory that produced it and resurfaced centuries later, stripped of bile and phlegm, in the 1928 work of psychologist William Moulton Marston. Marston never cited Hippocrates or the Aztecs when describing his four behavioral styles, but the underlying structure, four categories, two axes crossing them, is the same one the Greeks already sensed, and, apparently, so did the Aztecs, long before any personality test existed.

That same idea of four broad behavioral styles survives today, minus the bile and the elements, in the language of DISC’s colors: red, yellow, green, and blue. Wondering which of those four colors fits you best? The DISC 4 Colors test shows you in a few minutes.