What is a stated belief in phrenology regarding personality traits?

Phrenology, a now-discredited field of study, posited that the shape and contours of the human skull could provide insight into an individual's personality traits and mental faculties. The fundamental belief of phrenologists was that different areas of the brain corresponded to different characteristics or traits, and these areas could be inferred through the bumps and indentations on the skull.

This premise suggested that by assessing the physical structure of a person’s skull, one could gain insights into their personality, intelligence, and behavioral tendencies. Therefore, the notion that personality traits could be determined by skull shape is central to the concept of phrenology.

In contrast, views that personality traits are solely learned behaviors, unrelated to physical features, or influenced only by environmental factors do not align with the key principles of phrenology, which specifically linked physical attributes, particularly the skull, to personality characteristics.