Based on his early observations about the skull sizes and facial features of his classmates, Gall developed the theory of Organology and the method of Cranioscopy that would later be known as Phrenology.
Gall's version of Organology states that the mind is a collection of independent entities housed within the brain.
Cranioscopy is a method to determine the personality and development of mental and moral faculties on the basis of the external shape of the skull.
During his lifetime, Gall collected and observed over 120 skulls in order to test his hypotheses.

Gall believed that the bumps and uneven geography of the human skull were caused by pressure exerted from the brain underneath.
He divided the brain into sections that corresponded to certain behaviors and traits that he called fundamental faculties.
This is referred to as localization of function.
Gall believed there were 27 fundamental faculties, among them were: recollection of people, mechanical ability, talent for poetry, love of property, and even a murder instinct.
Based on the surface of a person's skull, Gall could make assumptions about that person's fundamental faculties and therefore their character.

Gall disagreed with Philippe Pinel and Peter Camper that the larger brain the larger one's intellectual power.
However, after numerous dissections and observations he was able to assert that a mature skull under 14 inches in circumference was not able to function normally.
Based on his early observations about the skull sizes and facial features of his classmates, Gall developed the theory of Organology and the method of Cranioscopy that would later be known as Phrenology. Gall's version of Organology states that the mind is a collection of independent entities housed within the brain. Cranioscopy is a method to determine the personality and development of mental and moral faculties on the basis of the external shape of the skull. During his lifetime, Gall collected and observed over 120 skulls in order to test his hypotheses.
Gall believed that the bumps and uneven geography of the human skull were caused by pressure exerted from the brain underneath. He divided the brain into sections that corresponded to certain behaviors and traits that he called fundamental faculties. This is referred to as localization of function. Gall believed there were 27 fundamental faculties, among them were: recollection of people, mechanical ability, talent for poetry, love of property, and even a murder instinct. Based on the surface of a person's skull, Gall could make assumptions about that person's fundamental faculties and therefore their character.
Gall disagreed with Philippe Pinel and Peter Camper that the larger brain the larger one's intellectual power. However, after numerous dissections and observations he was able to assert that a mature skull under 14 inches in circumference was not able to function normally.
Franz Joseph Gall