Stanford prison experiment
1971 CE.
Shown on the map at 37.429°, -122.173°.
The Stanford prison experiment (SPE), also referred to as the Zimbardo prison experiment (ZPE), was a controversial psychological experiment performed in August 1971 at Stanford University. It was designed to be a two-week simulation of a prison environment that examined the effects of situational variables on participants' reactions and behaviors. Stanford psychology professor Philip Zimbardo managed the research team that administered the study. Participants were recruited from the local community through an advertisement in the newspapers offering US$15 (equivalent to $119.25 in 2025) per day to male college students who agreed to participate in a "psychological study of prison life". Twenty-four participants were chosen after assessments of psychological stability and then assigned randomly to the role of prisoners or prison guards. Critics have questioned the validity of these methods. Those volunteers selected to be "guards" were given uniforms designed specifically to de-individuate them, and they were instructed to prevent prisoners from escaping. The experiment started officially when "prisoners" were arrested by the real police of Palo Alto, California.
Text from the Wikipedia article Stanford prison experiment, licensed CC BY-SA 4.0.