☛This category overlaps with philosophy and medicine.

Observations on the Deranged Manifestations of the Mind, or Insanity. By J. G. Spurzheim, M. D. First American edition, with notes, improvements, and plates. With an appendix by A. Brigham, M. D. Boston: Marsh, Capen & Lyon, 1833. —Spurzheim was one of the leading early promoters of phrenology (see our page of Quackery and Humbugs).

Sigmund Freud.

Totem and Taboo. Resemblances between the psychic lives of savages and neurotics. By Professor Dr. Sigmund Freud, LL.D. Authorized English translation with introduction by A. A. Brill. New York: Moffat, Yard and Company, 1919.