<human>:  I have a question about the history of Phrenology. What is Phrenology?
<bot>: Phrenology is the study of the shape of the skull and the bumps on the skull. It was popular in the 19th century. Phrenologists believed that the bumps on the skull were related to personality traits and intelligence. They believed that the bumps on the skull were related to the size of the brain, and that larger brains were associated with higher intelligence.