Phrenology (from Greek: φρήν, phrēn, "mind"; and λόγος, logos, "knowledge") is a theory which claims to be able to determine character, personality traits and criminality on the basis of the shape of the head (i.e., by reading "bumps" and "fissures"). Developed by German physician Franz Joseph Gall around 1800, the discipline was very popular in the 19th century. In 1843, François Magendie referred to phrenology as "a pseudo-science of the present day" Phrenology thinking was, however, influential in 19th century psychiatry and modern neuroscience. Phrenology is based on the concept that the brain is the organ of the mind, and that certain brain areas have localized, specific functions (see in particular, Brodmann's areas) or modules (see modularity of mind). In other words, phrenologists believed that the mind has a set of different mental faculties, with each particular faculty represented in a different portion (or organ) of the brain. These areas were said to be proportional to a given individual's propensities and the importance of a given mental faculty, as well as the overall conformation of the cranial bone to reflect differences among individuals.
Phrenology, which focuses on personality and character, should be distinguished from craniometry, which is the study of skull size, weight and shape, and physiognomy, the study of facial features. However, these disciplines have claimed the ability to predict personality traits or intelligence (in fields such as anthropology/ethnology), and were sometimes posed to scientifically justify racism.
The attempt to locate faculties of personality within the head can be compared to the attempt of philosopher Aristotle of ancient Greece to localize anger in the liver. However, the first attempts to scientifically measure skull shape and its alleged relation to character were performed by the German physician Franz Joseph Gall (1758-1828), who is considered the founding father of phrenology. Gall was one of the first to consider the brain to be the source of all mental activity.
In the introduction to his main work The Anatomy and Physiology of the Nervous System in General, and of the Brain in Particular, Gall makes the following statement in regard to his doctrinal principles, which comprise the intellectual foundation of phrenology:
- That moral and intellectual faculties are innate
- That their exercise or manifestation depends on organization
- That the brain is the organ of all the propensities, sentiments and faculties
- That the brain is composed of as many particular organs as there are propensities, sentiments and faculties which differ essentially from each other.
- That the form of the head or cranium represents the form of the brain, and thus reflects the relative development of the brain organs.
Through careful observation and extensive experimentation, Gall believed he had linked aspects of character, called faculties, to precise organs in the brain. Gall's most important collaborator was Johann Spurzheim (1776-1832), who successfully disseminated phrenology in the United Kingdom and the United States. He popularized the term phrenology.
Other significant authors on the subject include the Scottish brothers George Combe (1788-1858) and Andrew Combe (1797-1847). George Combe was the author of some of the most popular works on phrenology and mental hygiene, e.g., The Constitution of Man and Elements of Phrenology.
The American brothers Lorenzo Niles Fowler (1811-1896) and Orson Squire Fowler (1809-1887) were leading phrenologists of their time. Orson, together with associates Samuel Wells and Nelson Sizer, ran the phrenological firm and publishing house Fowlers & Wells in New York City. Lorenzo spent much of his life in England where he set up the famous phrenological publishing house, L.N Fowler & Co., where he gained considerable fame with his phrenology head (a china head showing the phrenological faculties), which has become a symbol of the discipline.
In the Victorian age, phrenology was often taken quite seriously. Many prominent public figures such as the Reverend Henry Ward Beecher (a college classmate and initial partner of Orson Fowler) actively promoted phrenology as a source of psychological insight and personal growth. British Prime Minister Lloyd George was known to have a keen interest in the subject, once contriving a meeting with C.P. Snow after noticing that the author had "an interestingly shaped head." Thousands of people consulted phrenologists to get advice in various matters, such as hiring personnel or finding suitable marriage partners. However, phrenology was rejected by mainstream academia, and was excluded from the British Association for the Advancement of Science. The popularity of phrenology fluctuated throughout the 19th century, with some researchers comparing the field to astrology, chiromancy, or merely a fairground attraction, while others wrote serious scientific articles on the subject.
Phrenology was also very popular in the United States, where automatic devices for phrenological analysis were devised. One such Automatic Electric Phrenometer is displayed in the Collection of Questionable Medical Devices in the Science Museum of Minnesota in Saint Paul.
In the early 20th century, phrenology benefitted from revived interest, partly fueled by the studies of evolutionism, criminology and anthropology (as pursued by Cesare Lombroso). The most prominent British phrenologist of the 20th century was the famous London psychiatrist Bernard Hollander (1864-1934). His main works, The Mental Function of the Brain (1901) and Scientific Phrenology (1902) are an appraisal of the Gall's teachings. Hollander introduced a quantitative approach to the phrenological diagnosis, defining a methodology for measuring the skull, and comparing the measurements with statistical averages.
Phrenology was practiced by some scientists promoting racist ideologies, including Nazism. They used phrenological claims, among other biological evidence, as a scientific basis for Aryan racial superiority.
In Belgium, Paul Bouts (1900-1999) began studying phrenology from a pedagogical background, using the phrenological analysis to define an individual pedagogy. Combining phrenology with typology and graphology, he coined a global approach known as psychognomy.
Prof. Bouts, a Roman Catholic priest, became the main promoter of renewed 20th century interest in phrenology and psychognomy in Belgium. He was also active in Brazil and Canada, where he founded institutes for characterology. His works Psychognomie and Les Grandioses Destinées individuelle et humaine dans la lumière de la Caractérologie et de l'Evolution cérébro-cranienne are considered standard works in the field. In the latter work, which examines the subject of paleoanthropology, Bouts developed a teleological and orthogenetical view on a perfecting evolution, from the paleo-encephalical skull shapes of prehistoric man, which he considered still prevalent in criminals and savages, towards a higher form of mankind. Bouts died on March 7, 1999, after which his work has been continued by the Dutch foundation PPP (Per Pulchritudinem in Pulchritudine), operated by Anette Müller, one of Bouts' students.
In the 1930's Belgian colonial authorities in Rwanda used phrenology to explain the so-called superiority of Tutsis over Hutus, thus laying the groundwork for the Rwandan genocide of 1994. "Leave None to Tell the Story: Genocide in Rwanada" Alison des Forges
Empirical refutation induced most scientists to abandon phrenology as a science by the early 20th century. For example, various cases were observed of clearly aggressive persons displaying a well-developed "benevolent organ", findings that contradicted the logic of the discipline. With advances in the studies of psychology and psychiatry, many scientists became skeptical of the claim that human character can be determined by simple, external measures.
Phrenology was a complex process that involved feeling the bumps in the skull to determine an individual's psychological attributes. Franz Joseph Gall first believed that the brain was made up of 27 individual 'organs' that created one's personality, with the first 19 of these 'organs' believed to exist in other animal species. Phrenologists would run their fingertips and palms over the skulls of their patients to feel for enlargements or indentations. The phrenologist would usually take measurements of the overall head size using a caliper. With this information, the phrenologist would assess the character and temperament of the patient and address each of the 27 "brain organs". This type of analysis was used to predict the kinds of relationships and behaviors to which the patient was prone. In its heyday during the 1820s-1840s, phrenology was often used to predict a child's future life, to assess prospective marriage partners and to provide background checks for job applicants.
Gall's list of the "brain organs" was lengthy and specific, as he believed that each bump or indentation in a patient's skull corresponded to his "brain map". An enlarged bump meant that the patient utilized that particular "organ" extensively. The 27 areas were highly varied in function, from sense of color, to the likelihood of religiosity, to the potential to commit murder. Each of the 27 "brain organs" was found in a specific area of the skull. As the phrenologist felt the skull, he could refer to a numbered diagram showing where each functional area was believed to be located.
The 27 "brain organs" were:
- The instinct of reproduction (located in the cerebellum).
- The love of one's offspring.
- Affection and friendship.
- The instinct of self-defense and courage; the tendency to get into fights.
- The carnivorous instinct; the tendency to murder.
- Guile; acuteness; cleverness.
- The feeling of property; the instinct of stocking up on food (in animals); covetousness; the tendency to steal.
- Pride; arrogance; haughtiness; love of authority; loftiness.
- Vanity; ambition; love of glory (a quality "beneficent for the individual and for society").
- Circumspection; forethought.
- The memory of things; the memory of facts; educability; perfectibility.
- The sense of places; of space proportions.
- The memory of people; the sense of people.
- The memory of words.
- The sense of language; of speech.
- The sense of colors.
- The sense of sounds; the gift of music.
- The sense of connectedness between numbers.
- The sense of mechanics, of construction; the talent for architecture.
- Comparative sagacity.
- The sense of metaphysics.
- The sense of satire; the sense of witticism.
- The poetical talent.
- Kindness; benevolence; gentleness; compassion; sensitivity; moral sense.
- The faculty to imitate; the mimic.
- The organ of religion.
- The firmness of purpose; constancy; perseverance; obstinacy.
Phrenology as a pseudoscience
Phrenology has long been dismissed as a pseudoscience, in the wake of neurological advances. During the discipline's heyday, phrenologists including Gall committed many errors in the name of science. In the book, The Beginner's Guide to Scientific Method by Stephen S. Carey, it is explained that pseudoscience can be defined as "fallacious applications of the scientific method" by today's standards. Phrenologists inferred dubious inferences between bumps in people's skulls and their personalities, claiming that the bumps were the determinant of personality. Some of the more valid assumptions of phrenology (e.g., that mental processes can be localized in the brain) remain in modern neuroimaging techniques and modularity of mind theory. Through advancements in modern medicine and neuroscience, the scientific community has generally concluded that feeling conformations of the outer skull is not an accurate predictor of behavior.
- Charlotte Brontë, as well as her two famous Brontë sisters, display the belief in phrenology in their works.
- The television personality Stephen Colbert, played by the comedian of the same name, claims to be a proponent of phrenology. In the February 8, 2007 episode of The Colbert Report, Colbert waved off "speculation" about a presidential bid, claiming that he must first sit down with his family, and his phrenologist. "I know these lumps are trying to tell me something." He said, adding, "Phrenology is the study of lumps on your head. It'd be another good campaign slogan." 
- Popular Indian-English writer Amitav Ghosh's first novel The Circle of Reason (1986) has one of the main characters, Balaram practice phrenology obsessively.
- On the popular television sitcom The Simpsons, the character Mr. Burns practiced phrenology in the episode "Mother Simpson", prompting his assistant Smithers to inform him that it was "dismissed as quackery 160 years ago."
- Terry Pratchett, in his Discworld series of books, describes the practice of Retro-phrenology as the practice of altering someone's character by giving them bumps on the head. You can go into a shop in Ankh-Morpork and order an artistic temperament with a tendency to introspection. What you actually get is hit on the head with a large hammer, but it keeps the money in circulation and gives people something to do. This was first described in Mr Midshipman Easy, where a vacuum pump was used to enlarge organs.
- The comedy-musical play Heid (pronounced 'Heed', a Scottish inflection of the word 'Head') by Forbes Masson alluded to the phrenology work of George Combe, citing the pseudoscience's influence on a young Charles Darwin as an inspiration for writers.
- The hip-hop group The Roots released an album in 2002 called Phrenology, using the term to discuss race.
- The film Pi depicts the main character, Max, outlining a portion of his skull according to a phrenology chart and proceeding to drill into that section to destroy a part of his brain that contained important information of a mathematical sequence that he thought nobody should know.
- The film Men at Work contains a joke about a phrenology bust.
- Several literary critics have noted the influence of phrenology (and physiognomy) in Edgar Allan Poe's fiction.
- In the episode "Duh Bomb" in the TV show Kenan & Kel, a woman practices phrenology on Kel's head.
- The Online store "Inner Coma Clothing Co.." Refers to the section of the site that sells hats as its "Phrenology" section.
- The cover art of the Bob Schneider album Lonelyland depicts a phrenology chart.
- In the computer game American McGee's Alice, a phrenology chart appears on the wall of the initial room in the level Skool Daze. A portion on the back of the neck is labeled "fear" (in place of "sublimity" on the original chart).
- In the They Might Be Giants album The Else, the song "Contrecoup" mentions phrenology at numerous points throughout the song.
- Phrenology and other 19th century medicinal practices are humorously parodied in the game manual for Freddy Pharkas: Frontier Pharmacist. You can read the manual here.
- In the novel The War of the End of the World from the well-known latin american writer Mario Vargas Llosa, one of the main characters is Galileo Gall, who is phrenologist and had adopted his new name because of Galileo Galilei and Franz Joseph Gall, founder of the science of phrenology. 
- Magendie, F (1843) An Elementary Treatise on Human Physiology. 5th Ed. Tr. John Revere. New York: Harper, p 150. (note the hyphen).
- Simpson, D. (2005) Phrenology and the neurosciences: contributions of F. J. Gall and J. G. Spurzheim ANZ Journal of Surgery. Oxford. Vol.75.6; p.475
- Fodor, Jerry A. (1983). Modularity of Mind: An Essay on Faculty Psychology. Cambridge, Mass.: MIT Press. ISBN 0-262-56025-9 p.14, 23, 131 See also, Modularity of mind
- Edward Hungerford. "Poe and Phrenology", American Literature 1(1930): 209-31.
- Erik Grayson. "Weird Science, Weirder Unity: Phrenology and Physiognomy in Edgar Allan Poe" Mode 1 (2005): 56-77. Also online.
- Phrenology: an Overview includes The History of Phrenology by John van Wyhe, PhD.
- The Phrenology Pages, a Belgian site advocating phrenology.
- Phrenology. The History of Cerebral Localization. Article by Renato M.E. Sabbatini, PhD in Brain & Mind online article.
- Phrenology Today! Russian portal, advocating phrenology. Articles on so-called modern phrenology.
- Examples of phrenological tools can be seen in The Museum of Questionable Medical Devices, in Minneapolis, Minnesota, U.S..
- Joseph Vimont: Traité de phrénologie humaine et comparée. (Paris, 1832-1835). Selected pages scanned from the original work. Historical Anatomies on the Web. US National Library of Medicine.
- Phrenology: History of a Classic Pseudoscience - by Steven Novella MD
- Historical Deadwood Newspaper accounts of C. R. Broadbent well known speaker on Phrenology and Physiology visit Deadwood SD 1878
- The Skeptic's Dictionary by Robert Todd Carroll
- Who Named It? Franz Joseph Gall Biography of Franz Joseph Gall and his creation: Phrenology.
- Phrenology by George Burgess (1829-1905) George Burgess, Phrenologist in Bristol, England 1861-1901.
- Corrective Phrenology