Phrenology, from the Greek words phren, meaning “mind,” and logos, meaning “knowledge,” is based on the belief that human behavior originated in the brain. This was a major departure from earlier beliefs that focused on the four humors as the source of emotions and behaviors: (1) sanguine (blood), seated in the liver and associated with courage and love; (2) choleric (yellow bile), seated in the gall bladder and associated with anger and bad temper; (3) melancholic (black bile), seated in the spleen and associated with depression, sadness, and irritability; and (4) phlegmatic (phlegm), seated in the brain and lungs and associated with calmness and lack of excitability. Theoretically and practically relocating responsibility for behavior from various organs to the brain represented a major step in the development of the scientific study of behavior and in the development of biological explanations of crime and criminality.
1. Franz Joseph Gall (1758–1828)
Around 1800, Franz Joseph Gall, a German neuroanatomist and physiologist who pioneered study of the human brain as the source of mental faculties, developed the practice of cranioscopy, a technique by which to infer behaviors and characteristics from external examination of the skull (cranium). According to Gall, a person’s strengths, weaknesses, morals, proclivities, character, and personality could be determined by physical characteristics of his or her skull.
Gall mapped out the location of 27 “brain organs” on the human skull. A bump or depression in a particular area of the skull would indicate a strength or weakness in that particular area. For example, several areas of Gall’s map of the skull were believed to correspond to that person’s tendencies to engage in criminal or deviant acts. One area corresponded to the tendency to commit murder; another area corresponded to the tendency to steal. Although not widely accepted in Europe, the English elite (and others) used Gall’s ideas to justify the oppression of individuals whose skulls had bumps or depressions in the wrong areas. The practice also was widely accepted in America between 1820 and 1850. Although crude, and somewhat ridiculous by today’s standards, Gall’s efforts had significant impact on subsequent research that attempted to identify the brain as the origin of behavior. Although similar to physiognomy in that it tried to make inferences about character and behavior from outward characteristics, cranioscopy attempted to correlate those outward physical characteristics to internal physical characteristics (i.e., brain shape), which was a significant advance.
2. Johann Spurzheim (1776–1832)
Spurzheim, a German physician and student of Gall’s, actually coined the term phrenology to replace cranioscopy. Spurzheim also expanded the map of the brain organs, developed a hierarchical system of the organs, and created a model “phrenology bust” that depicted the location of the brain organs.
While the German scientists were focusing attention on the brain as an important determinant of individual behavior, various other scholars were theorizing about the development of man as a biological organism; about the nature of social and political organizations; and about the place of man, as an individual, within those organizations. The synthesis of these ideas would significantly advance the progress of research related to biological perspectives of behavior.