Phrenology is a pseudoscience that emerged in the early 19th century, founded by Franz Joseph Gall. It posits that the shape and size of the skull can reveal information about a person's character and mental abilities. Proponents believed that different areas of the brain corresponded to specific traits, and that these could be assessed by examining the bumps and indentations on the skull. Despite its popularity in the 1800s, phrenology has been widely discredited by modern science. Advances in neuroscience have shown that personality and intelligence are influenced by a complex interplay of genetics, environment, and brain function, rather than the physical shape of the skull.