1487 The Inquisition's guide to the diagnosis, behavior, trial and punishment of witches--the "Malleus Maleficarum" (or "The Witch Hammer")--was endorsed on May 19 by the Faculty of Theology at the University of Cologne. "Malleus" went through 19 editions in the next two centuries and provided a basis for gruesome tortures of people with deviant behavior.
1857 On May 11, Sir Charles Locock first described potassium bromide therapy for epilepsy. Locock believed that epilepsy was caused by masturbation and knew that bromide reduced libido. The drug worked, but not for Locock's reasons. In the 1930s, Tracy Putnam and Frederick Gibbs at Boston City Hospital showed that epilepsy was accompanied by synchronous nervous discharge in the brain.
1882 On May 1, G. Stanley Hall was appointed to the post of lecturer at Johns Hopkins University.
1937 On May 31, in a picture story titled "Rat Works Slot Machine for a Living," Life magazine described the performance of a rat named Pliny the Elder. Using the method of shaping, B.F. Skinner had trained Pliny to pull a chain to release a marble, pick up the marble and drop it in a box for a food reinforcement.
1971 On May 17, Washington became the first state to pass legislation banning discrimination on the basis of gender. Gender discrimination became a focus of the public policy interests of psychologists during this period.
1989 In Price Waterhouse v. Hopkins, the U.S. Supreme Court decided on May 1 that discrimination based on gender stereotyping had denied Ann Hopkins a partnership at Price Waterhouse. The case was the first to be influenced by testimony based on psychological research on gender stereotyping. Social psychologist Susan Fiske was the expert witness in the case.