Phrenology

Phrenology (from Greek φρήν (phrēn), meaning 'mind', and λόγος (logos), meaning 'knowledge') is a pseudomedicine primarily focused on measurements of the human skull, based on the concept that the brain is the organ of the mind, and that certain brain areas have localized, specific functions or modules. Although both of those ideas have a basis in reality, phrenology beyond empirical knowledge in a way that departed from science. Developed by German physician Franz Joseph Gall in 1796, the discipline was very popular in the 19th century, especially from about 1810 until 1840. The principal British centre for phrenology was Edinburgh, where the Edinburgh Phrenological Society was established in 1820.

Although now regarded as an obsolete amalgamation of primitive neuroanatomy with moral philosophy, phrenological thinking was influential in 19th-century psychiatry. Gall's assumption that character, thoughts, and emotions are located in specific parts of the brain is considered an important historical advance toward neuropsychology.

Phrenologists believe that the human mind has a set of various mental faculties, each one represented in a different area of the brain. For example, the faculty of "philoprogenitiveness", from the Greek for "love of offspring", was located centrally at the back of the head (see illustration of the chart from Webster's Academic Dictionary).

These areas were said to be proportional to a person's propensities. The importance of an organ was derived from relative size compared to other organs. It was believed that the cranial skull—like a glove on the hand—accommodates to the different sizes of these areas of the brain, so that a person's capacity for a given personality trait could be determined simply by measuring the area of the skull that overlies the corresponding area of the brain.

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