Some thinkers and physicians of the 18th and 19th centuries believed that the shape of a person’s skull could hold clues as to their psychology. In this Curiosities of Medical History feature, we take an in-depth look at this long-discredited “science,” known as phrenology.
In the 18th century, a new “science” started to amass interest in Europe: phrenology.
This science, which has been long since discredited, held that an experienced phrenologist would be able to tell what a person’s psychological inclinations and personality traits were just by feeling the shape of their skull.
The person who first popularized this notion was physician Franz Joseph Gall (1758–1828). He believed that the shape of a person’s brain held clues as to their personality and that it would also influence the shape of their skull.
Phrenology evolved and took on a life of its own throughout the 18th and 19th century, until its eventual decline at the turn of the century.
In this Curiosities of Medical History feature, we look at what believers of phrenology argued, why this pseudoscience was particularly problematic, and some of the ways in which it actually contributed to the development of neuroscience.
Gall did not refer to this science as “phrenology.” That term came into use later, in the early 1800s, when British physician T. I. M. Forster coined it.
It was Gall, however, who suggested the basis for this science. He wrote of “the possibility of distinguishing some of the dispositions and propensities [of an individual] by the shape of the head and skull.”
Gall believed not only that the shape of the skull held clues as to someone’s “predispositions” but also that each area of the brain was linked to a different characteristic.
In his view, this was true of both animals and humans, though he believed that humans had more and more varied mental and emotional capacities.
As psychologists Dr. Paul Eling, Prof. Stanely Finger, and Prof. Harry Whitaker write in a paper discussing the origin and development of Gall’s ideas:
“Gall would ultimately settle on 27 distinct higher functions or faculties of mind […]. Many of these functions, such as love of offspring and memory for locations, humans share with animals; some functions, including wit, poetry, and religion, are uniquely human.”
Some other “faculties” that Gall described include:
- the “instinct of generation, reproduction, or propagation”
- pride, or “hauteur, loftiness, elevation”
- the memory of things, of facts, “educability, perfectibility”
- talent for painting
- talent for music
- the “faculty of the relations of numbers”
- the “faculty of spoken language” or “talent of philology”
Gall also posited that the two hemispheres of the brain were practically interchangeable and held similar functions. He also believed that should one hemisphere sustain damage, the other could compensate.
Throughout the 19th century, Gall’s ideas spread widely through Europe and North America. This was partly thanks to a series of lectures he gave alongside his protege, physician Johann Kaspar Spurzheim, and partly thanks to other adepts of phrenology picking up his ideas.
One such adept was Scottish lawyer and phrenologist George Combe (1788–1858), who wrote about this pseudoscience in various books, including Elements of Phrenology, which he published in 1824.
In this book, Combe also lays out the view that different parts of the brain play different roles.
“The brain, […] being the organ of the mind, the next inquiry is, [w]hether is it a single part, manifesting the whole mind equally, or an aggregate of parts, each subserving a particular mental power? All the phenomena are at variance with the former, and in harmony with the latter, or phrenological, view,” he wrote.
“The brain must be a combination of parts performing distinct functions,” he argued. He had five reasons for this:
- “[A]ll the powers of the mind are not equally developed at the same time, but appear in succession at different periods of life.”
- A person who has musical talent may not be very skilled at painting, and vice versa, suggesting that different talents “reside” in different parts of the brain, which may be more or less developed.
- “[I]n dreaming, one or more faculties are awake while others are asleep; and if all acted through the instrumentality of one and the same organ, they could not be in opposite states at the same time.”
- Psychiatric issues affect certain behaviors and functions and not others, suggesting that each “faculty” is linked to a different part of the brain.
- “[P]artial injuries of the brain do not equally affect all the mental powers.”
Reportedly, Combe was such a believer in the accuracy of phrenology assessments that he only married his wife after they had both undergone such an examination to determine whether or not they were well suited for each other.
According to science historian Dr. Marc Renneville, “Phrenology was at the peak of its popularity in the 1830s,” when people in France, Britain, Spain, Germany, Scandinavian countries, and the United States were widely discussing its ideas.
However, Dr. Renneville also notes that in the second half of the 19th century, phrenology was already losing its popularity. He writes that “the palpation methods used by phrenologists gradually came to be assimilated with the various divinatory ‘sciences’ practiced by those trading in hopes and promises in the country’s traveling fairs and shows.”
Although the ideas that phrenology put forth may have been fascinating at the time, and although this pseudoscience did contribute to some real scientific progress in understanding how the brain works, it also contributed to solidifying some discriminatory notions.
For one, phrenology held that men’s and women’s skulls, and therefore their brains and mental capacities, were vastly different.
Phrenology’s relationship with women was a double-edged sword. On one hand, historians note that this “science” was more open to women practitioners than most other scientific fields in the 19th century, which tended to be all but exclusive to men.
At the same time, however, phrenological treatises emphasized ways in which women’s skulls allegedly differed from men’s, only to claim that this was due to certain qualities inherent to women that were not naturally present in men.
Citing 19th-century American phrenologist Orson Fowler (1809–1887), historian Dr. Carla Bittel explains that where “[m]en were distinguished by their firmness, force, self-esteem, courage, combativeness, and destructiveness; women were known for exquisiteness, emotion, susceptibility, and ‘devotion to offspring,’ as well as their secrecy, artifice, and nervousness.”
Some also used phrenology to uphold scientific racism — that is, the misuse of scientific and pseudoscientific ideas to claim that one race is superior to others.
In the 19th-century U.S., for instance, physician Charles Caldwell (1772–1853) used phrenological ideas in support of slavery. He claimed that individuals of African origin were unequal to Caucasians in their mental constitution — based only on the shape of their skulls.
Other contemporary physicians, such as Samuel George Morton (1799–1851), claimed something similar about American Indian populations to justify forcing them out of the territories where they originally lived.
Despite the fact that phrenology is not scientifically viable, some of its core ideas did pave the way for progress toward the development of an actual scientific field: neuroscience.
For instance, some of Gall’s original notions about how different parts of the brain were tied to different functions were important in forming a new understanding of how the brain works.
In a paper that appeared in the journal Surgical Neurology, Drs. Charles E. Rawlings III and Eugene Rossitch Jr. note that, first and foremost, Gall built on previously used methods of brain dissection in a way that allowed him to observe the anatomy of the brain with more precision and accuracy.
They write, “Almost exclusively, before Gall’s time, [brain] dissection was accomplished by gross sectioning that obviously precluded any substantial tracking of nerves or tracts.”
“Gall, instead of merely slicing the brain like a melon, would gently tease the fibers of the nerve or tract and follow them to their origin or destination. In this manner, he was able to contribute immensely not only to the anatomic knowledge of the brainstem, but also to neuroanatomy as a whole.”
Some researchers now argue that Gall’s work was crucial to the discovery of the phenomenon of aphasia — that is, an inability or difficulty to understand language or formulate coherent speech due to damage to a specific area of the brain.
That said, the person whose name is most closely linked to the discovery of the brain region tied to language and speech is French physician Paul Broca (1824–1880).
He lent his own name to Broca’s area, which is the brain region involved in speech, after describing two patients who had experienced injuries of that brain region that left them unable to formulate speech.
Broca’s discovery did not occur in a vacuum but in the context of already existing debates around the localization of speech in the brain. A central figure in this debate was French physician Jean-Baptiste Bouillaud (1796–1881), who had studied Gall’s writings on the human brain.
On February 21, 1825, Bouillaud presented his paper “Clinical research demonstrating that loss of speech results from a lesion of the anterior lobules of the brain and confirming M. Gall’s opinion on the seat of the organ of articulate language” at the National Academy of Medicine in Paris, France.
Researchers such as Drs. Jason W. Brown and Karen L. Chobor point out that later discoveries about the location of the speech function in the brain owe a debt to Gall’s original ideas.
“We know that the attribution of language to the frontal lobes was derived from Gall’s localization,” they write.
The path to where neuroscience is today has been a long and convoluted one, but strange and controversial approaches — such as that of phrenology — at least contributed to opening up new avenues for research and investigation into the mysteries of the human mind.