Background
In the summer of 1960, Timothy Leary was a 39-year-old lecturer at Harvard's Center for Research in Personality and a rising figure in clinical psychology. While vacationing in Cuernavaca, Mexico, Leary was offered psilocybin mushrooms by a local guide. The experience, which he later described as the most profound event of his life, convinced him that psychedelics could revolutionize psychology. He returned to Harvard determined to study psilocybin systematically.
Leary recruited Richard Alpert, a fellow Harvard psychology lecturer, and together they obtained pharmaceutical-grade psilocybin from Sandoz Laboratories in Basel, Switzerland -- the same company that had first synthesized LSD. The Harvard Psilocybin Project formally began in the fall of 1960, operating under the umbrella of the Center for Research in Personality.
The Experiments
The project's initial study administered psilocybin to 167 subjects between 1960 and 1961, including graduate students, artists, clergy, and professionals. Leary and Alpert collected detailed self-reports and psychological assessments. Their early findings were striking: the majority of participants reported the experience as profoundly positive, with lasting changes in outlook, creativity, and interpersonal relationships.
The Concord Prison Experiment (1961--1963)
One of the project's most ambitious arms was the Concord Prison Experiment, conducted at Concord State Prison in Massachusetts. The researchers administered psilocybin to 32 inmates, combined with group psychotherapy, to test whether the experience could reduce recidivism. Initial results appeared dramatic: Leary reported that only 25% of paroled subjects returned to prison within six months, compared to an expected rate of 64%. However, a 34-year follow-up study published in 1998 by Rick Doblin found that the long-term recidivism rate was essentially no different from the prison's baseline, though subjects who received psilocybin did report lasting subjective benefits.
The Good Friday Experiment (April 20, 1962)
The most scientifically rigorous study of the project was designed by Walter Pahnke, a graduate student at Harvard Divinity School, under Leary's supervision. On Good Friday 1962, twenty divinity students gathered at Boston University's Marsh Chapel. In a double-blind design, ten received 30 mg of psilocybin and ten received niacin as an active placebo. Nine of the ten psilocybin subjects reported experiences meeting the criteria for genuine mystical experience, compared to only one in the placebo group. A 25-year follow-up conducted in 1987 by Rick Doblin found that nearly all psilocybin subjects still described the experience as one of the high points of their spiritual lives. The study was later cited by Roland Griffiths of Johns Hopkins as a direct inspiration for his own landmark 2006 psilocybin research.
