History of the temperaments
How the sciences explained temperament
From Empedocles to today’s research, physicians, philosophers, physiologists, and psychologists have tried to answer the same question: why do people react so differently to the same situation? Each age changed the explanation, and often kept the names.
This is a short version. The full history will be a chapter of The Book of Temperaments.
When behavior became the definition
The four humors were born as a medical theory, not as a list of traits. Behavior entered the description of the types little by little.
- 4th c. onwardEach humor gets a portrait of character.
- Middle AgesThe signs of the body begin to be read as an index of the person.
- 1798Classification starts from observable effects.
- 20th c.Questionnaires and the laboratory measure temperament by behavior.
What science brought down
The fall of humoral physiology
The four temperaments were born of a physics and a medicine: four elements, four qualities, four humors. Between the 16th and 19th centuries, anatomy, physiology, and chemistry dismantled each of these pieces. There was no day when the humors were banned; each support was replaced by independent findings.
| Old piece | What science showed | What can no longer be claimed |
|---|---|---|
| Blood | Vesalius and Harvey: blood circulates and returns to the heart. | It can no longer be claimed that an excess of hot, moist blood produces the sanguine personality. |
| Air | Boyle and Lavoisier: air is a mixture of gases. | It can no longer be claimed that “air” is a simple substance that determines temperament. |
| Water | Lavoisier: water is a compound. | It can no longer be claimed that water is a cold, moist element of body and character. |
| Earth | Dalton and Mendeleev: dozens of elements. | It can no longer be claimed that earth is the cold, dry constituent of the melancholic. |
| Fire and qualities | Lavoisier and the physics of heat: combustion is a chemical reaction; heat is energy. | It can no longer be claimed that fire, hot, cold, dry, and moist are the causes of four characters. |
After the fall, the symbol
When the physiology fell, the names did not disappear. They were reinterpreted as images: blood became sociability, fire became initiative, earth became depth, water became tranquility. This symbolic reading may have literary value, but it is a later reinterpretation: the ancients were speaking of substances of the body, not of metaphors.
That is why a method that still explains temperament by elements, humors, colors, or symbols is not recovering an ancient science. It is repeating an explanation that science dismantled more than two centuries ago, or swapping the cause for an image.
The timeline
Antiquity
5th century BC to 4th century AD
5th c. BC
Philosophy of the soul
Empedocles
Explains matter by four roots: fire, air, water, and earth.
5th c. BC
Medicine
On the Nature of Man
The medical treatise presents the four humors: blood, phlegm, yellow bile, and black bile.
384–322 BC
Philosophy of the soul
Aristotle
Defines the soul as the form of the living body and distinguishes natural disposition, passion, and habit.
c. 129–216
Medicine
Galen
Systematizes temperament as a mixture: one balanced constitution and eight imbalances.
4th c. onward
Medicine
Texts attributed to Hippocrates and Galen
Later texts link each humor to a portrait of character. The quartet we know today is born.
Middle Ages
8th to 14th century
8th c.
Philosophy of the soul
Bede the Venerable
Records the first dated Latin table of the four portraits.
980–1037
Medicine
Avicenna
Develops the medicine of complexions and treats the rational soul in a separate work.
11th–13th c.
Medicine
School of Salerno
Easy-to-memorize verses spread the four types across Europe.
medieval circulation
Signs of the body
Secret of Secrets
A manual of government that proposes reading a person’s character from the signs of the body.
13th c.
Philosophy of the soul
Thomas Aquinas
The body disposes, passion inclines, the will decides.
The fall of humoral physiology
16th to 19th century
1543
Brain and physiology
Andreas Vesalius
Dissecting human bodies, he corrects Galen’s anatomy, much of which had been described from animals.
The authority of the text over the body falls.
1575
Brain and physiology
Juan Huarte de San Juan
Attributes to the brain the differences in wit and aptitude between people.
1628
Brain and physiology
William Harvey
Shows that blood is not endlessly produced and used up: the same blood circulates and returns to the heart.
Blood as a humor generated and spent falls.
1649
Philosophy of the soul
René Descartes
Separates the soul, which thinks, from the body, which works like a machine.
1661
Chemistry and physics
Robert Boyle
In The Sceptical Chymist, he disputes that bodies can be reduced to four elements.
The square of the elements begins to fall.
1689
Philosophy of the soul
John Locke
Admits inborn temperaments that education shapes but does not reverse.
1783–1789
Chemistry and physics
Antoine and Marie-Anne Lavoisier
Explain combustion by oxygen and show that water is a compound and air is a mixture of gases.
Fire, water, and air cease to be elements.
1798
Psychology and measurement
Immanuel Kant
Classifies the four temperaments by their observable effects, without the humors.
1802
Brain and physiology
Pierre Cabanis
Links the temperaments to the nervous system and the organization of the body.
1808
Chemistry and physics
John Dalton
Proposes atomic theory: each element is a kind of atom, and compounds have definite proportions.
“Earth” ceases to be a single element.
1810–1840
Signs of the body
Phrenology
Tries to read faculties of the mind from the shape of the skull. The idea proved false.
1869
Chemistry and physics
Dmitri Mendeleev
Arranges dozens of elements in the periodic table.
The four elements no longer have a place in chemistry.
1869
Psychology and measurement
Francis Galton
Begins to measure individual differences across the population.
1870s
Psychology and measurement
Wilhelm Wundt
Reorganizes the four types by the strength and speed of the emotions.
20th century
the laboratory on one side, symbol and product on the other
1905–1909
Psychology and measurement
Heymans and Wiersma
Study temperament through questionnaires given to thousands of people.
1909
Symbolic and popular readings
Rudolf Steiner
Presents the four temperaments anew in anthroposophy, for education and self-knowledge, with no basis in physiology or experimental psychology.
The humor becomes a symbol.
1920s
Brain and physiology
Ivan Pavlov
Links the types to properties of the nervous system observed in dogs.
1921
Psychology and measurement
Carl Gustav Jung
Proposes the psychological types and the distinction between extroversion and introversion.
1928 · 1970s
Symbolic and popular readings
Marston and DISC
Four patterns of behavior become a family of commercial tests for companies.
The type becomes a profiling product.
1940–1966
Symbolic and popular readings
Pastoral and self-help manuals
The four names get lists of strengths and weaknesses and circulate in churches, schools, and best-selling books.
The old table returns without the cause that held it up.
1947
Psychology and measurement
Hans Eysenck
Finds two broad statistical dimensions of personality.
1956
Science of temperament
Thomas and Chess
Follow children for decades and describe temperament as the “how” of behavior.
1970
Brain and physiology
Jeffrey Gray
Describes brain systems of approach, conflict, and defense.
1980s
Science of temperament
Jerome Kagan
Shows that reactivity in infants is related to inhibition in the face of the unfamiliar.
1980s
Science of temperament
Mary Rothbart
Defines temperament by reactivity and self-regulation.
1990
Psychology and measurement
Big Five
Five broad factors come to organize personality research.
1993
Psychology and measurement
C. Robert Cloninger
Separates temperament from character.
21st century
emotion, body, and brain
2000–2020
Brain and physiology
Affective neuroscience
Research on emotion, interoception, and regulation shows that the same act can arise from different processes.
2010s
Psychology and measurement
RDoC and HiTOP
Psychiatry begins to study dimensions and functional systems instead of fixed boxes.
2020
Axis Ratio
Axis Ratio
Igor R. O. Carneiro begins developing the Axis Ratio Method: two axes, four genera, and twelve species, with no humors, no elements, and no symbols as cause.
Where the lines converge.
2020
Axis Ratio: where the lines converge
The Axis Ratio Method, by Igor R. O. Carneiro, developed since 2020, is born where these lines meet: medicine, the philosophy of the soul, physiology, and psychology. It does not explain temperament by humors, elements, or symbols. It organizes it into two axes, four genera, and twelve species.
The names survive; the explanation is different.