Phrenology was popular in the 19th century but is now discredited as a pseudoscience. Phrenologists in the past believed they could determine character traits from skull shapes.
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Cultural Reference
Literature and films sometimes portray phrenologists to evoke a historical or pseudoscientific theme. The character in the period drama consulted a phrenologist about his future.
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Archaic Term
The term is outdated; modern neuroscience has replaced phrenology. A neuroscientist today would not consider a phrenologist's theories scientifically valid.