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Dennis and Terence McKenna papers

 Collection — Multiple Containers
Identifier: MSP 213

Scope and Contents

The Dennis and Terence McKenna papers (1943-2016; 2.5 cubic feet) document the lives and intellectual pursuits of Dennis J. McKenna and Terence K. McKenna. Subjects include shamanism, eschatology, and plant hallucinogens. The collection includes but is not limited to unpublished manuscripts, field reports, journals of personal reflections, term papers, correspondence, photographs, and article reprints. As much as the materials in this collection reflect the McKenna’s scientific and technical training, so too do they capture their philosophical beliefs about the mysteries of time, reality, and existence. Donated in multiple accessions over several years, the McKenna papers are organized into five series.


  • 1943 - 2016


Conditions Governing Access

This collection is open for research.

Biographical or Historical Information

Dennis Jon McKenna was born on December 17, 1950 in Paonia, Colorado. He received a B.A. in biology from the University of Colorado in 1973, an M.A. in botany from the University of Hawaii in 1979, and a Ph.D. in botanical sciences from the University of British Columbia in 1984. Dennis received post-doctoral research fellowships in the Laboratory of Clinical Pharmacology at the National Institute of Mental Health and in the Department of Neurology at Stanford University School of Medicine. He joined Shaman Pharmaceuticals as Director of Ethnopharmacology in 1990 and relocated to Minnesota in 1993 to join the Aveda Corporation as Senior Research Pharmacognosist. In 2001, Dennis joined the faculty of the Center for Spirituality and Healing at the University of Minnesota. Dennis was a key organizer and participant in the Hoasca Project, an international biomedical study of ayahuasca used by indigenous people and syncretic religious groups in Brazil. He is also a founding board member of the Heffter Research Institute and serves on the advisory board of non-profit organizations in the fields of ethnobotany and botanical medicines. At Heffter, he continues his focus on the therapeutic uses of psychoactive medicines derived from nature and used in indigenous ethnomedical practices. Dennis is author or co-author on over forty scientific papers in peer-reviewed journals. His publications have appeared in the Journal of Ethnopharmacology, European Journal of Pharmacology, Brain Research, Journal of Neuroscience, Journal of Neurochemistry, Economic Botany, Alternative and Complementary Therapies, and elsewhere. Terence Kemp McKenna, Dennis’s older brother and psychedelic author, is another significant figure in this collection. Terence was born on November 16, 1946 in Paonia, Colorado. He studied history at U.C. Berkeley in 1965 and later enrolled at the Tussman Experimental College. After completing the College’s two-year program, Terence withdrew from the University of California, though he maintained his position as a laboratory assistant in the Entomology Department, where he prepared insect specimens for the collection of the California Insect Survey. From October 1967 to March 1968, Terence travelled widely in Europe, Asia, Africa, and South America. Upon his return to the US, Terence worked as a gardener and sold fabrics and trinkets that he acquired abroad. He returned to India in 1969, seeking to study Tibetan languages and religion. Terence supported himself by collecting and selling specimens of exotic butterflies to buyers in Singapore and America. In 1970, he moved to Japan, where he worked as an English teacher. Upon hearing of his mother’s illness, Terence moved to Vancouver, where he found employment as a restaurant worker. Following his mother’s death, he moved to Colombia, where Terence and Dennis later performed "the experiment at La Chorrera." In 1971, Dennis and Terrence traveled to La Chorrera, the ancestral home of the Witoto people in the Colombian Amazon, in search of oo-koo-hé, a DMT-containing plant. Companion researchers accompanied the brothers, and the group was collectively known as the Brotherhood of the Screaming Abyss. The experiment occurred on March 4, wherein Dennis and Terence consumed a brew of plant hallucinogens, aiming to fabricate an artifact that would be the fusion of mind and matter. The brothers recounted the details of what happened in La Chorrera in their 1975 book The Invisible Landscape. Terence wrote about his experience more directly in his 1993 book True Hallucinations. Likewise, Dennis published a more extensive account in 2012 under the title The Brotherhood of the Screaming Abyss: My Life with Terence McKenna. In 1975, Terence graduated from Berkeley with a B.S. in ecology, resource conservation, and shamanism. In 1976, Terence and Dennis pseudonymously published one of the earliest psilocybin mushroom growing guides under the names O.T. Oss and O.N. Oeric. In 1985, Terence co-founded the non-profit Botanical Dimensions, with his then-wife Kathleen Harrison-McKenna. The organization aimed to collect and propagate medicinal and shamanic plants and fungi from around the world. Throughout the 1990s, Terence wrote and lectured widely about shamanism, ethnopharmacology, and plant hallucinogens. He spent the last few years of his life in Hawaii and died of brain cancer in 2000 at the age of 53.

Note written by McKenna, Dennis J., 1950 -


2.50 Cubic Feet

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0.50 Cubic Feet

0.50 Cubic Feet

0.50 Cubic Feet

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Language of Materials


Arrangement Note

The Dennis and Terence McKenna papers have been arranged into five series: 1. Dennis J. McKenna Materials, 1968-2016 (0.75 cubic feet) 2. Terence K. McKenna Materials, 1965-2000 (0.75 cubic feet) 3. Photographs and Slides, 1943-2004 (0.50 cubic feet) 4. Books and Manuscripts, 1972-2000 (0.25 cubic feet) 5. Miscellaneous Materials, 1994-2011 (0.25 cubic feet)

Source of Acquisition

Dennis J. McKenna

Accruals and Additions

Multiple donations by Dennis J. McKenna: April 26, 2013; January 31, 2016.

Existence and Location of Copies

Digital reproductions of materials are available for research use. See our digital collections database e-Archives: Dennis and Terence McKenna papers
Dennis and Terence McKenna papers
In Progress
Lauren N. Haslem
Description rules
Describing Archives: A Content Standard
Language of description
Script of description

Revision Statements

  • 2021-11-11: Updated name of collection to include Terence McKenna by Stephanie Schmitz.

Repository Details

Part of the Purdue University Archives and Special Collections Repository

504 Mitch Daniels Boulevard
West Lafayette Indiana 47907 United States