The pseudoscience of phrenology, the study of skull shapes as an indicator of mental abilities, was founded by German physiologist Franz Joseph Gall in the early 1800s. Gall claimed that the brain has multiple “organs” that each correspond to different mental traits or abilities. Because the human skull is shaped as it is because of the brain, he claimed that the study of the shape, size and geography of the human skull could yield information about these “organs” and the consequent mental capacity of the person to whom it belonged. This field of study was based on a faulty science in which evidence that helps prove a researcher’s hypothesis is taken into consideration. When this pseudoscience spread to the U.S. around the 1830s, it was used to prove prevalent yet baseless hypotheses about the inferiority of non-white races.
The U.S. in the 1830s and 1840s, when phrenology became popular, was struggling to justify the continuation of slavery in the face of a growing abolitionist movement and was dealing with interactions between white western settlers and existing Native American populations. In the case of slavery, physicians such as Charles Caldwell used phrenology to attempt to prove that African people were in their rightful place as slaves. Caldwell studied the skulls of many different peoples, including Africans, at the Musee de Phrenologie in Paris. In 1837, he concluded that the skulls of African people (a flawed generalization of an entire continent of diverse peoples) indicated a “tamableness” that made them suited to be slaves, and required them to “have a master”. This view of people of African descent as inherently mentally inferior contributed to the continuation of slavery and the segregation and racism that still persists in the U.S..
In the case of Native Americans, the work of physiologists including Samuel Morton helped justify their removal from their land in the 1830s and 40s. Morton’s 1839 book “Crania Americana” detailed skull configurations and consequent mental capacities of the four “separate species” he defined, including whites and Native Americans. He saw differences between races as natural and dictated by God, rejecting the view that physical differences were created by environments. His study of skulls concluded that Native American minds were “different than that of the white man” and was cited in articles targeted at western settlers encountering Native Americans. One article stated that Native Americans were “adverse to cultivation, slow in acquiring knowledge”. This view of Native Americans existence in society as not conducive to industrialization and “progress” helped justify Andrew Jackson’s Indian removal policies and allowed western settlers to continue taking the land of Native Americans.
The flawed use of “science” to support exploitation of groups of people helped perpetuate racial oppression and distorted future views of the biological basis of race.