Phrenology and the Grand Delusion of Experience
In the nineteenth century, phrenology was hugely influential despite being totally invalid. Its history shows why we must be skeptical of any belief based solely on experience.
Phrenology. The science of picking the pocket through the scalp.
— Ambrose Bierce, The Devil’s Dictionary, 1911
Today, phrenology (“head reading”) is usually seen as the fossilized stuff of cranks and charlatans. But in the nineteenth century it had a huge influence at all levels of Western society, more than all of its later competitors (such as psychoanalysis) put together. It was influential because of its attractive philosophy and because practitioners and clients saw that it worked. But we now know that it could not possibly work; personal experience had led millions of people astray. Indeed, few beliefs can match phrenology for its extent of influence and certainty of invalidity. So it has valuable lessons about any experience-based belief.
In the nineteenth century, phrenology affected all levels of Western life and thought. In Britain, Europe, and America, its influence was felt in anthropology, criminology, education, medicine, psychiatry, art, and literature. In France, it eroded established power and led to wide social changes. In Australia, it rationalized the violence against Aborigines and explained the criminality of convicts. For ordinary people everywhere a head reading was often required for employment or marriage.1 But how could this happen if phrenology was totally invalid? For answers, we need to start at the beginning.
First Steps to Delusion
Around 1790, the German-born anatomist Franz Joseph Gall, one of the founders of modern neurology, put together his skull doctrine that later led to phrenology. He held that behavior such as painting or being careful had their own specialized organs in the brain, and that they influenced the shape of the skull. So the skull’s bumps would indicate behavior and abilities that were innate. Gall spent eleven years examining hundreds of heads to test his ideas: “If ... he observed any mechanician, musician, sculptor, draughtsman, mathematician, endowed with such or such faculty from birth, he examined their heads to see whether he might point out a particular development of some cerebral part.... He also called together in his house common people, as coachmen and poor boys, and excited them to make him acquainted with their characters” (Spurzheim 1815, 271).
Gall’s seemingly logical approach had two fatal defects. First, his claims were often based on a single striking case, for example “Cautiousness” was placed above the ears because an extremely cautious priest had a large bump there. Second, Gall looked only for confirming cases and ignored disconfirming cases, a flaw not lost on his critics. Thus David Skae (1847), a physician at the Royal Edinburgh Asylum, noted that once the truth is “fixed upon our minds,” looking for confirmation is “the most perfect recipe for making a phrenologist that could well be devised.” But to Gall and the thousands of phrenologists who came later, personal experience mattered more than procedural defects. Phrenology had taken its first giant step on the road to delusion.2 Note that the delusion of experience is not limited to artifacts of reasoning such as the Barnum effect.
Spurzheim Nails the Coffin Shut
The next step was due to Johann Spurzheim, Gall’s coworker. Gall had linked brain organs to behavior, but Spurzheim held that organs cannot relate to behavior, only to traits. Gall disagreed (the origin of traits was then a complete mystery), arguing that every person has imagination whereas not every person can paint. So in 1813, Spurzheim broke away. He renamed organs after the traits said to underlie behavior, invented organs to cover apparent gaps, and in due course adopted the name phrenology (a name suggested in 1815 by the naturalist Thomas Forster from the Greek words for mind and discourse). The focus was now on speculative divisions of the mind. Since behavior was now related more or less vaguely to several traits, and therefore more or less vaguely to several brain organs, everything was now open to interpretation. In one hit, Spurzheim had moved the system from a biological science to a mental philosophy; from observation to nonfalsifiability. It was the classic pseudoscientific move. Grand delusions were now inevitable.
Feel the Bumps, Know the Man
In those days, the workings of the brain were largely unknown. The idea of the four humors was still popular, as was bloodletting. Traits of ability and of character were held to be equal in all men at birth and were wholly determined by upbringing. To claim otherwise was a crime against morality and God.
But phrenology did claim otherwise. It said traits were innate, localized in the brain, and measurable by head shape. What was once a mystery was now widely seen as an exact science. If true, it promised to revolutionize just about everything.
But it was not true. Phrenology was partly right about brain functions being localized but wrong about the actual functions. Not slightly wrong; totally wrong. The brain involves processes such as moving, touching, hearing, and seeing, not phrenological traits such as neatness, curiosity, love of children, attachment to home, and relish for food.3 As shown by modern imaging techniques, some of these processes are localized in distinct regions, while others are distributed and interactive. But all are sufficiently diversified that brain damage or cell loss may have no noticeable effect. The same techniques have shown that the claimed phrenological organs do not exist.
Nor is brain size a measure of power to the extent claimed by phrenologists. So we can look at phrenology knowing that a certain head shape cannot possibly mean what it is supposed to mean. Few beliefs about man can match phrenology for such certainty of invalidity.4
Unsurprisingly, phrenology copped unceasing parody. A modern example appeared in the U.K.’s Independent Long Weekend of January 11, 1997, suggesting how “to improve people’s personalities by rearranging their head bumps. With a mallet. Do not try this at home” (p. 2).
What attracted millions of converts and made phrenology historically important was the appeal of its philosophy. By offering a recipe for living and self-improvement based not on metaphysics but on claims testable by experience, phrenology was a dream come true. And in the 1810s it took off like a rocket; first in Europe, then Britain, then America.
The average life expectancy in Britain (adjusted for high infant mortality) at that time was forty years, a quarter of the population was illiterate, few homes had running water or even a clock, and a phrenology book cost a quarter of the average weekly wage. Yet in less than twenty years about thirty phrenological societies were formed, and roughly one person in 3,000 was “moderately well instructed in phrenology, [more] than there are of persons equally advanced in geology, entomology, botany, astronomy, or similar sciences” (Watson 1836, 223).
But by implying that man rather than God was in charge, phrenology created an unceasing storm of religious and moral protest. Critics said it reduced the soul to anatomy and gave too much power to ordinary people. Nevertheless, it attracted people of intelligence and a vast responsive literature wherein every criticism was furiously attacked.5
When critics said (in tracts of paralyzing wordiness) “there is no evidence favoring phrenology but much favoring Christianity, so we prefer the latter,” the reply was “if there is no God, what is the organ of Veneration for?” When critics said “phrenology is without intellectual challenge and suits only the coarsest taste,” the reply was “it is so simple and natural that ordinary people can put it to immediate use.”
Soon there was a runaway demand for character readings, and by the 1840s phrenology had divided into two camps: one a fortune-telling scam where a travelling phrenologist could earn more in a week than in a whole year of farm laboring; the other a serious study whose journals were filled with alarms against the impostors. (The later parallel with newspaper astrology is unmistakable here.) Both camps promoted phrenology as a matter not of belief but of demonstration. Test-it-and-see was an essential part of the message. So how could an actually invalid phrenology survive such a process? First, a look at replies to stock objections.
Phrenologists felt they had convincing replies to every stock objection: The skull varies in thickness. Not enough to matter. Everything relates to size not quality. Experience shows that phrenology works. Stomachs digest different foods, so why can’t brain organs do different things? Stomachs may be versatile but their function is the same. Parts of the brain can be destroyed without apparent effect, so how can traits be localized? The investigators were ignorant of phrenology and missed the relevant behavior.
But other objections were ignored. Organs could be in layers (so head shape could be meaningless?), the same organ appears on both sides of the head (so we believe with one and disbelieve with the other?), important traits such as sympathy and love of truth are missing, and worst of all any head can be made to fit any behavior so nobody could know if phrenology was wrong. For example, a small Combativeness could still be combative due to a large Firmness, a large Destructiveness, or a large Approbation (fights to gain admiration). Spurzheim’s nonfalsifiability was working well. But phrenologists were not interested. Why worry when there were testimonials?
Critics of New Age beliefs “typically encounter anecdotes and testimonials where there ought to be rigorous pre- and post-treatment comparisons” (Beyerstein 1990, 33). Phrenology provides a definitive test of testimonials because it had lots of them, even from the very top:
“I never knew I had an inventive talent until phrenology told me. I was a stranger to myself until then” (Thomas Edison). “The phrenologist has shown that he is able to read character like an open book ... with an accuracy that the most intimate friends cannot approach” (Alfred Russel Wallace, cofounder of the theory of evolution). “I declare that the phrenological system of mental philosophy is as much better than all other systems as the electric light is better than the tallow dip” (William Gladstone, four times prime minister of England). All are from Severn (1913, 6).
There were also countless testimonials from ordinary people. “Scarcely a day passes that the editor of the Phrenological Journal does not receive some outburst of thankfulness from a grateful recipient of needed counsel” (Sizer and Drayton 1899). “35,000 testimonials” said a sign in the window of a London phrenologist (see picture in Parker and Parker 1988, 34). How could 35,000 clients be wrong, to say nothing of Edison, Wallace, and Gladstone? The answer boils down to experience. And wishful thinking.
In 1929, the British Phrenological Society published thirty testimonials entitled The Revival of Phrenology: The Phrenological Principles and Localisations Confirmed by Modern Scientists. None mentioned the results of actual tests, yet they supposedly showed that “the main principles of phrenology can no longer be disputed.”
Yes, phrenology seemed to work. It was the apparent accuracy of readings that was so convincing to practitioners and clients. It was “so plainly demonstrated that the non-acceptance of Phrenology is next to impossible” (British Phrenological Association 1896, 64).
For example, Severn (1929, 84) cites a reading of himself, made when he was twenty-five, that “was a remarkably true description ... probably the best I have ever had.” Here are some excerpts: “Great firmness and reality of purpose. The mind is sensitive and active. The judgement is keen, and logical in its conclusions. He is not very original, but may be in his habits. Fond of reform and improvements of all kinds [note the contradiction]. He loves truth, and will have it at any price. The mind is sceptical and too honest to believe without reasonable evidence. A lover of moral and personal liberty. Is warm-hearted.” More on this later.
The phrenologist Stackpool O’Dell (1925, 12) explains how “in his daily experience, when he says that a child has unusual talent for drawing, he finds that it is so, or when he says of another that he has exceptional musical capacity, it proves correct.... He judges these points by the shape of the head, and a due consideration of temperament. And ... his conclusions, in most instances, will be recognised as strikingly correct.”
The experience of George Combe, the most famous British practitioner of his time, seems even more convincing. In 1829, he visited a Dublin asylum to demonstrate phrenology to its doctors who, when his readings of selected inmates were over, compared them with their own diagnoses. For a male aged thirty-seven Combe found “predisposed to melancholy” versus the diagnosis “melancholy, great timidity of disposition.” For a female aged forty-eight Combe found “self-esteem is predominant” versus “monomania, pride.” There were sixteen hits as good as these, two nearly as good, one miss, and four passes with “no grounds for inference.” In general, the outcome was “completely in harmony with what was anticipated.” Combe’s many visits to prisons and other asylums were just as successful (Williams 1894).
In short, people saw how phrenology seemed to work and were convinced. Experience was the only game in town. But how could people be convinced if phrenology was totally invalid?
The problem in the above cases is that there are no controls to guard against delusion. In Severn’s case, the reading is either very general (so anyone would agree with it) or is guessable from personal contact. In O’Dell’s case, we cannot tell if his hits are genuine or are due to circumstances, including not wanting to be seen disagreeing with a renowned phrenologist.
This is similarly true in Combe’s case, which allowed cueing by the subject’s appearance and by sensing the attitudes of those present. Given a timid, fearful subject, or a proud disdainful one, together with reciting aloud the often opposing indications, and no doubt a practiced skill in reading human nature and onlookers, Combe could hardly go wrong. Indeed, he almost never mentions unobservable phenomena such as abilities, preferring things like melancholy (a term then applied to any personal distress) and propensity to thieving, both consistent with a dependence on cues. If this failed, the result could always be explained by an opposing organ, by upbringing, or by declaring that criticism comes from men and not Nature—and only Nature had the authority to say whether phrenology was true or not.
Alternatively, failures could simply be ignored, as when Severn (1929, 83) visited O’Dell and asked if he could be a phrenologist. “He examined my head and pointed out so many mental faculties detrimental to my acquiring proficiency that I gave up further thought of qualifying professionally.” Yet he became a top British phrenologist! Notice how easily the obviously wrong reading was ignored.
To their credit, not every believer remained a believer. American psychologist Herbert Spencer (1820–1903) practiced phrenology and invented a device to improve the measurement of cranial features, but he later abandoned phrenology as unscientific.
The British botanist Hewett Watson, author of the 1836 survey Statistics of Phrenology, was convinced of phrenology’s validity. But after three years as editor of the Phrenological Journal, which “obliged him to make more close scrutiny into various points,” he saw that much “is doubtful, if not erroneous.” Given a choice between upsetting believers and promoting nonsense, he preferred to resign (Watson 1840).
The following study, the only one of its kind that I could find, shows how a simple control uncovers the delusion. A female patient aged twenty-two of Morgenthaler (1930), a Swiss psychiatrist, was amazed at the penetrating accuracy of her phrenological reading. It had twenty-six statements such as: “You are a blend of natural feelings and much stronger emotions. You are a definite female, which explains your weaknesses. You are not sharply focused. Critical judgments give way to warm-hearted feelings.” So Morgenthaler asked ten female subjects to judge how well each statement applied to them. An average of 70 percent said the statements were definitely or probably correct, 13 percent were uncertain, and 17 percent said they were definitely or probably wrong. It was the classic Barnum approach to instant delusion. The subjects knew the reading was not theirs; otherwise their acceptance might have been even higher.
Bird Brains Tell All
In the 1840s, the eminent French physiologist Pierre Flourens introduced the experimental approach that phrenologists had steadfastly rejected. He found that the intellect in pigeons and chickens gradually weakened as the brain was cut away, but still remained even when very little brain was left, which effectively demolished the claims of phrenology. A similar point had been made earlier by the American anatomy professor Thomas Sewall. So the need to test actual people disappeared, ironically just at the time when the rise of experimental psychology would have made such tests possible. But enough tests were made to confirm the expected negative results.
Some tests were obvious. When a phrenologist was given the supposed head cast of an eminent professor (it was actually the cast of a large turnip), the reading emphasized wisdom and intelligence (U.K.’s Times newspaper, February 2, 1824). When the humorist Mark Twain visited Lorenzo Fowler (under a fictitious name) he was told he had no sense of humor, but on a repeat visit under his own name he had “the loftiest bump of humor” ever encountered (Twain 1959; Lopez 2002).
Skae (1847), mentioned earlier, made a test that today would seem just as obvious. He went to the Phrenological Society’s collection of head casts, picked ten famous cases “whose character was well known,” measured the elevation of each organ by calipers, and corrected it by the cube root of head size shown by immersion in water. “I assumed that the measurements of the crania thus calculated would correspond with the known characters of the individuals, if phrenology was true.” But the results were “generally speaking at variance with phrenology, and in many instances so utterly irreconcilable with its truth, as to appear altogether subversive of it.” The ten casts had not shown the bumps that phrenology said they should.
The response by phrenologists to Skae’s results was polemic, lengthy, and largely irrelevant. To them, the principles of phrenology were absolute; therefore, negative results were sure proof of incompetence. They said the correction for head size was inappropriate, and that the phrenologist’s eye and hand were sensitive to nuances missed by calipers.6 Skae then challenged them to get positive results from his data but they declined, arguing that the unsoundness of his measurements “entirely vitiates every conclusion to which they have been supposed to lead.”7
Nearly eighty years later, Cleeton and Knight (1924) read physiognomy and phrenology books to find out what each cranial feature meant, but they found “great disagreement.” So they selected ten traits such as IQ, sociability, and willpower for which the disagreement was least. They then recruited twenty-eight adults, measured their cranial features, and had their traits rated by twenty close associates who knew all twenty-eight subjects. The results showed no link between cranial features and traits. Of 201 correlations, four were significant (p=0.04) versus six expected by chance. The mean correlation was a negligible 0.004.
Slow to Die
The above tests confirmed that phrenology cannot deliver benefits beyond those due to non-phrenological factors. But phrenology was slow to die. In the 1950s, phrenologists still existed in Britain and in the larger American cities (Dallenbach 1955). Today there is at least one pro-phrenology website, so supporters are not yet extinct.8 But in practice, phrenology “lasted only long enough to become one of the most thoroughly discredited theories in the history of physiological psychology” (Uttal 2001, 102). It “was the most popular of all the doctrines of psychology in the whole history of the science, and at the same time the most erroneous. It affords a striking example of the danger of erecting a vast superstructure on inadequate observation and inexact methods” (Flugel 1964, 36–37). “Eventually phrenology lost out to science and to public indignation, and degenerated into a sect of zealous extremists unable to pass on discredited knowledge to a new more enlightened generation” (Van Wyhe 2002).
Neglect of Scientific Caution
It is easy to see why the scientifically invalid phrenology could have been so popular. To millions of people it was so fashionable and so satisfying, and its invalidity was so invisible, that it could not fail to work. Their experience of phrenology could not fail to be convincing. But it was a delusion. And all due to a neglect of scientific caution.9, 10
We might hope that such neglect is less likely today. But the literature of any experience-based belief shows it to be raging out of control on every page. As with phrenology, believers refuse to accept that experience is unreliable; they brush aside contrary evidence and dismiss critics as bigoted and closed-minded. They don’t want to know. Neglect of scientific caution is much more fun.
For believers, the lesson is that experience means nothing without controlled tests. In the Encyclopedia Britannica, phrenology now occupies one paragraph whereas it once occupied many pages.
For skeptics, the lesson is that the delusion of experience should never be underestimated. It dies only when believers die. Reformers should forget the present generation and target the next.11
1. The historical importance of phrenology was not widely documented until after the 1960s, when science historians became sensitive to social considerations. Today it has been minutely examined in scholarly books, articles, at least twenty PhD theses, and various websites, of which easily the most comprehensive is John van Wyhe’s www.historyofphrenology.org.uk/. But these sources are invariably concerned with social issues and not the role of experience in the acceptance of phrenology. Indeed, the literature of phrenology is so clogged with side issues (of philosophy, of politics, of religion, of morality, of society in general), so often tedious to read (wordiness being the style of the day), and so hard to find (notwithstanding the many early publications now available online via the above website), that the role of experience has been largely unexamined. The source material for this article includes books and journals previously in the library of the British Phrenological Society and now held by the University of London.
2. Jerison (1977) argues that Gall went wrong in the same way that others went right. Gall happened to pick the wrong hypothesis and spent the rest of his life trying to prove it. Ironically, Gall failed not because he was reductionist but because he was not reductionist enough. Had he reduced brain organs to simple things like toe-twitches and thumb-tingles, he would have found success because only such simple functions are localizable in the brain.
3. The record for odd traits, albeit in physiognomy rather than phrenology, must go to Joseph Simms who, in a 600-page book running to at least ten editions by 1891, proposed Aquasorbitiveness (love of water), Mnemoniconominality (ability to remember names, presumably the author had it), Morivalorosity (moral courage), Philomonotopicalness (love of one particular place), Temporinaturalitiveness (appreciation of time passing), and many others.
4. We have a certainty here well beyond that presently possible in, say, psychoanalysis. But we should not go overboard. Phrenology for all its faults led to the discovery that brain and mind were associated and that localization existed. Along the way it established function as a psychological term, popularized the expression of traits on scales such as one to five, and confirmed the futility of purely metaphysical speculations about the nature of man. Which is why phrenology appears in every history of psychology, unlike unproductive beliefs such as astrology.
5. During 1801–1889, The Index to the English Catalogue of Books recorded a total of eighty-five phrenology titles versus sixteen astrology, fifteen physiognomy, and six palmistry (graphology did not appear until the 1870s in France). In 1928, after forty years of searching through libraries in America, Britain, France, and Germany, the phrenologist John Melville estimated that about 4,000 books and pamphlets had been published on phrenology (Severn 1929, 438, 442). Best sellers included George Combe’s Constitution of Man (500,000 in sixty years), Fowler’s Phrenological Self-Instructor (250,000), and Sizer and Drayton’s Heads and Faces (150,000). For comparison, works by popular novelists such as Dickens typically sold 50,000 copies. Today the British Library has about 300 phrenology books and pamphlets, the New York Public Library about 400.
6. That the supposed sensitivity of the phrenologist’s eye and hand led to delusion is shown by phrenology’s golden rule, namely size=power. Other things being equal, the bigger the head the better. What could be more reasonable? Thus Severn (1913, 20), who in thirty years as a practicing phrenologist had examined more than 100,000 heads, or roughly fifteen each working day, says, “Persons of commanding mentality invariably have heads above the average size.” But ten scientific studies of IQ versus head size involving a total of more than 11,000 adults found a mean correlation of only 0.13 (based on data in Wickett et al. 1994), which is too small to be observable by phrenologists—indeed their observations should have denied it. So their claim was a case of believing is seeing. Nevertheless their claim was not entirely wrong, for the correlation between IQ and actual brain size (as opposed to head size) measured by magnetic resonance imaging is about 0.4 (Rushton 1997).
7. Phrenology had one disadvantage seldom admitted by phrenologists, especially in their response to critics, because “In numberless instances, [plaster] casts form our only source of phrenological observation” (Hytche 1844). Most enthusiasts had a collection, in rare cases exceeding one or two thousand casts. But applying plaster of Paris to a thickly lathered and oiled head was quite unpleasant for the subject. The setting plaster prevented free respiration and generated much heat, whereupon some subjects “become so nervous, that the features are distorted, and ... the very character of the head becomes changed.” Due to bunched-up hair, or to expansion of the setting plaster, “the cast is always larger than the head [in diameter by an inch or more] ... when we consider the additional energy conferred by every extra inch of healthy brain, we shall perceive how different will be our estimate of cerebral power.” So when using casts, “in ninety-nine cases out of a hundred our judgement is likely to be incorrect” (Hytche 1844).
8. The largest (and very user-friendly) pro-phrenology website is www.phrenology.org operated out of Belgium. It proclaims “Phrenology is a true science.... Today, much of the criticism against Phrenology can be easily dismissed. Extensive experimental verification of the Phrenological localisations have proved their practical value.” No experimental verifications are cited. Nearly 700 images, mostly of heads, can be found by Googling phrenology > images.
9. Whether the price paid for such neglect is worth whatever satisfaction it brings, including keeping people off the streets, is a topic that skeptics might like to ponder. The problem of course is that a belief may be a crutch, but hearts are not won by kicking away crutches.
10. The satisfaction brought to clients by a warm and sympathetic phrenologist should be self-evident. The satisfaction brought to phrenologists may be less evident but is beautifully expressed by Severn (1929, 504): “It is a great career, and a splendid and glorious mission to be a phrenologist. There is life and vitality in the work, and though it may not yield big financial gains, in a thousand ways it will amply repay such as are adapted to the calling, and are desirous of doing great good in the world, and of being of immense service to their fellow creatures. I have frequently said that notwithstanding all the adverse circumstances I have experienced, if I had a hundred lives, I would devote them all absolutely and wholly to phrenology.”
11. Among the exhibits at the Minneapolis Museum of Questionable Medical Devices are machines with a headpiece of thirty-two mechanical probes, each with five contact points to measure size on a five-point scale. In ninety seconds it will print out for each of thirty-two phrenological organs a brief reading with moral overtones. “Secretiveness – Average – You are fairly secretive but can improve. You tell things to your friends. Don’t do it.” The readings are popular (fifty a day) and are billed as entertainment, but many people see them as accurate and are unwilling to accept that phrenology is invalid. The delusion of experience is alive and well. From McCoy (1985; 1996).
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———. 1929. Life Story and Experiences of a Phrenologist. Brighton: Severn. An endearing account of forty years of experience including how he married his wife on the basis of phrenology two months after meeting her, since when “we have neither of us had the slightest reason to regret the step we had seemingly so hastily taken” (p. 157).
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———. 1840. Editorial. Phrenological Journal 13: 386–387.
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