Thomas Metzinger is a renowned German philosopher. He has a longtime fascination with psychedelics, stemming from his own experience and also from his work as an analytic philosopher. He says altered states of consciousness give us profound insights into the nature of the mind. And he believes modern society has an ethical imperative to foster a “culture of consciousness.”

Original Air Date: August 02, 2025

Interviews In This Hour: 

Guests:
Thomas Metzinger

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Most psychedelic stories are highly personal, but there’s a different dynamic when two people share the experience — especially a married couple. Steve talks with theoretical physicist Marcelo Gleiser and clinical psychologist Kari Gleiser about their transformative experiences.

Original Air Date: May 9, 2025

Guests:
Marcelo Gleiser, Kari Gleiser

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For more from Luminous: ttbook.org/luminous

Chris Timmerman is a neuroscientist with a deep interest in phenomenology—what’s actually happening in our minds during psychedelic experiences. He leads the DMT Research Group at Imperial College, where he’s found that a single psychedelic experience can transform a person’s belief system, often turning materialists into panpsychists. In this wide-ranging conversation, Steve talks with Chris about everything from fractals and ayahuasca ceremonies to whether scientists who study psychedelics should talk openly about their own experiences.

Original Air Date: March 01, 2025

Guests:
Chris Timmerman

More from Luminous: ttbook.org/luminous

Buddhist meditation and psychedelic journeys have a lot of shared DNA—both take you deep inside your mind and can change your life. But many Buddhists say psychedelics violate the prohibition against intoxicants. Do they? Spring Washam straddles this divide as both a Buddhist teacher and founder of an ayahuasca church. Her own story is fascinating—how she’s merged these two practices.

Original Air Date: January 25, 2025

Guests:
Spring Washam

More from Luminous: ttbook.org/luminous

There’s a huge question swirling around the really big psychedelic experiences. Are these mind-blowing trips just hallucinations – the brain shot full of chemicals, playing tricks on you - or do they crack open some transpersonal dimension of consciousness? Most scholars who study psychedelics won’t go anywhere near this question, and yet it’s central to how you interpret these experiences. If you’re in psychedelic-assisted therapy, you want to know if this glimpse of the divine was real or just some figment of your imagination. Philosopher Peter Sjöstedt-Hughes believes we need a metaphysics of psychedelics to explain these powerful experiences.

Original Air Date: November 30, 2024

Interviews In This Hour:

Guests:
Peter Sjöstedt-Hughes

For more from Luminous: ttbook.org/luminous

Psychedelic people are practicing at the very edge of anyone else’s comfort zone,” says psychologist Katherine MacLean, author of the psychedelic memoir “Midnight Water.” MacLean was a pioneering psychedelic researcher at Johns Hopkins, who then left her job to pursue her own unconventional psychedelic journey. She talks with Steve Paulson about her work as a psychedelic guide, her personal history with psychoactive substances, and why she reveres the Mexican healer Maria Sabina.

Original Air Date: August 30, 2024

Guests:
Katherine MacLean

For more from Luminous: ttbook.org/luminous

Erik Davis’ “Blotter” is really three books in one: It’s about the way LSD tabs were embedded in blotter paper so they wouldn’t be detected by the authorities; it’s also a deep dive into the psychedelic underground; and finally, it’s an art book — gorgeously illustrated, with lots of very trippy blotter art. Steve talks with Erik about the wildness of psychedelic experiences and whether they reveal a deeper dimension of consciousness.

Original Air Date: July 20, 2024

Guests:
Erik Davis

For more from Luminous: ttbook.org/luminous

Brian Muraresku makes the controversial argument that the famous Eleusinian Mysteries were fueled by a psychedelic wine. And he speculates that this secret ceremony, with its mind-altering drugs, became the Eucharist — the foundational event of early Christianity.

Original Air Date: May 04, 2024

Guests: 

Brian Muraresku

More from Luminous: ttbook.org/luminous

It’s remarkable how fast psychedelics have gone mainstream. Just look at how so many major universities are racing to set up their own psychedelic institutes. Psilocybin and MDMA are now considered the most promising treatments for depression and PTSD that we’ve had in decades. But this is not the first time psychoactive drugs were hailed as miracle cures. Heroin and cocaine were also once considered wonder drugs. Today, what’s so striking is how the public conversation about psychedelics ignores this deeper history of intoxicants.

British historian Mike Jay wants to challenge this narrative of psychedelic “exceptionalism.” In his book “Psychonauts: Drugs and the Making of the Modern Mind,” he digs into the 19th century’s rich history of psychoactive experiences — and tells the story of seminal figures like Humphry Davy, Sigmund Freud and William James – and lots of other people I’d never heard of.

Jay is also upfront about his own psychedelic experiences. He’s had plenty of them. And he believes the scientists and doctors who study psychedelics should talk more openly about their own mind-altering experiences — which is definitely not the case for most of them.

Original Air Date: January 27, 2024

Guests:

Mike Jay

Further Reading:

"Psychonauts Drugs and the Making of the Modern Mind"—Nautilus: "Why Scientists Need to Get High"

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For all the talk about how psychedelics might transform psychiatric care, there's still a fascinating question at the heart of psychedelic science. Is it the mind-blowing experience that fundamentally changes a person’s outlook on life? Or is it the powerful molecules that rewire the brain?

Check out more from the series at ttbook.org/luminous.

Original Air Date: December 16, 2023

Interviews In This Hour:

Does psychedelic therapy need the trip? — Will psychedelics replace antidepressants? — Spiritual warriors in the psychedelic underground

Guests:

David Olson, Charles Raison, Rachel Harris

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