Who would have been most likely to claim that a slight protrusion in a certain region of someone's skull would indicate that the individual had an optimistic personality?

Franz Joseph Gall, the founder of phrenology, would have been most likely to make such a claim. Phrenology posited that the shape and bumps of the skull could reveal an individual's character traits and personality. Gall believed that specific areas of the brain were responsible for different aspects of personality, and a protrusion in a certain region could be interpreted as a sign of optimism or other traits.