During the early heyday of phrenology in the 1820s to 1840s, many employers could require a morality reference from a local phrenologist to ensure that a potential employee was honest and diligent. This belief that protuberances on the skull provided an accurate clue to talents and abilities was particularly pushed to be applied to education and criminal justice reform. Phrenologists, similar to those who now believe in strong limits in the “left brain” or “right-brained,” thought they could determine the most appropriate career for young people and match potential partners more accurately than “old-fashioned love.” The visit of a phrenologist was comparable to seeking the advice of so-called clairvoyants, clairvoyants or astrologers today. A phrenologist was someone who claimed to have access to special knowledge about people. The ignorant and gullible were particularly sensitive to the claims of phrenologists. Gall noted that the cerebral cortex of humans was much larger than that of animals, which he believed made humans intellectually superior. Eventually, he came to believe that the physical characteristics of the cortex can also be seen in the shape and size of the skull. Reviews from well-known brain researchers have played an important role in this reversal of popular views on phrenology. The American brothers Lorenzo Niles Fowler (1811-1896) and Orson Squire Fowler (1809-1887) were the leading phrenologists of their time.
Orson, along with Samuel Robert Wells and Nelson Sizer, ran the phrenological firm and publishing house Fowlers & Wells in New York. During this time, Lorenzo spent much of his life in England, where he founded the famous phrenological publishing house L. N. Fowler & Co. and gained considerable fame with its phrenological head (a porcelain head that shows phrenological abilities), which has become a symbol of the discipline.  Orson Fowler was known for his octagonal house. But I`m far less interested in crusades for or against phrenology than I am in your happiness at Ivy Cottage. Phrenology was widely discredited as a scientific theory in the 1840s.
This was only partly due to a growing body of evidence against phrenology.  Phrenologists have never been able to agree on the most basic number of mental organs, which has increased from 27 to over 40, and have had difficulty locating mental organs. Phrenologists relied on cranioscopic measurements of the skull to find the position of the organs.  Jean Pierre Flourens` experiments on pigeon brains showed that the loss of parts of the brain did not cause any loss of function or the loss of a function completely different from that which phrenology had attributed to it. Flourens` experiment, though imperfect, seemed to suggest that Gall`s alleged organs were imaginary.   Scholars have also been disillusioned with phrenology since it has been exploited by middle- and working-class entrepreneurs by entrepreneurs. Popularization had led to the simplification of phrenology and the mixing of the principles of physionomonia, which had been rejected from the outset by Gall as an indicator of personality.  Phrenology has been tainted from the outset by accusations of promoting materialism and atheism and destroying morality. All these factors led to the disappearance of phrenology.   Recent studies using modern technologies such as magnetic resonance imaging have further refuted phrenology`s claims.  In the 1930s, Belgian colonial authorities in Rwanda used phrenology to explain the alleged superiority of Tutsis over Hutus.
 Phrenology, the study of the conformation of the skull as an indication of mental abilities and character traits, especially according to the hypotheses of Franz Joseph Gall (1758-1828), a German physician, and 19th century disciples such as Johann Kaspar Spurzheim (1776-1832) and George Combe (1788-1858). Phrenology enjoyed great popularity until the 20th century, but was completely discredited by scientific research. In his book on phrenology, Gall suggested that moral and intellectual abilities are innate. In other words, people are born with their moral character and intelligence. If you were a thief, it was because you were born with a predisposition to deceive. Johann Spurzheim was Gall`s most important collaborator. He worked as Gall`s anatomist until 1813, when they had a permanent dispute for unknown reasons. Under his own name, Spurzheim successfully published phrenology throughout the United Kingdom during his lecture tours in 1814 and 1815, and in 1832 in the United States, where he died.  Phrenological teachings had become a widespread popular movement in 1834 when Combe came to the United States to lecture.  Men like the Fowlers saw business opportunities and became phrenologists, seeking additional ways to bring phrenology to the masses.  Although it was a popular movement, the intellectual elite in the United States found phrenology attractive because it provided an observational biological explanation of mental processes, but was not accepted without criticism. Some intellectuals have accepted organology while questioning cranioscopy.  Gradually, the popular success of phrenology undermined its scientific merits in the United States and elsewhere, as well as its materialist foundations that promoted radical religious views.
There was growing evidence to refute phrenological claims, and by the 1840s it had largely lost credibility.  In the United States, particularly in the South, phrenology encountered an additional obstacle in the anti-slavery movement. While phrenologists generally claimed the superiority of the European race, they often sympathized with liberal causes such as the anti-slavery movement; This sowed skepticism about phrenology among those who were pro-slavery.  The rise and rise of the popularity of mesmerism, phrenomesmerism, has also contributed to the loss of interest in phrenology among intellectuals and the general public.   More recently, graduates of the University of Oxford have conducted an empirical study to rigorously justify or debunk phrenology claims. Using MRI, scalp curvature to brain gyrification (gyri are brain combs) and scalp lifestyle measurements, the researchers concluded that there was no evidence that scalp curvature was related to individual characteristics or that phrenological analysis produced statistically significant effects. Phrenology arose at a time when scientific procedures and standards for acceptable evidence were still codified.  In the context of Victorian society, phrenology was a respectable scientific theory.