I've got a little pile of rocks on my desk. It's not as weird as it sounds. They're small, smooth stones I've picked up during vacations to various beaches. It's a habit I picked up from my mom, who always took home some piece of the beach that she could hold when she returned to her life in a landlocked state.

For me, the six stones are a reminder of things that are bigger than whatever daily stress is eating away at my psyche. A reminder that, despite the chaos and trauma in this life, in this world, at this moment, it is all still ephemeral. The rocks stay. Then the rough edges smooth over time and ultimately they dissolve into sediment and blow away into the air or get swept away by the water.

On top of this small assortment of rocks is a relatively new addition: a gold-plated medallion about the size of a quarter. On one side, the words "Meditation" and, underneath, "The true method of knowledge is experiment," from the poet William Blake. On the other side, there's an engraved image of mushrooms and a kind of blessing: "May you remain aware of awareness."

A scientist named Roland Griffiths gave that medallion to me. He and I talked back in April as one of the first conversations in this series. Griffiths had spent the later stage of his career exploring the ways that psychedelic drugs, specifically psilocybin, could help patients with depression, addiction issues and even terminal cancer. Then two years ago, he himself was diagnosed with stage 4 colon cancer. The doctor was now the patient, and Griffiths was facing his own mortality.

I was changed by our conversation. First of all, he was the person who finally convinced me to delve more deeply into meditation — a practice he credits with helping him navigate the closing chapter of his life. And that's the part that really stuck with me, how Griffiths was able to sit with his dying. Or, rather, sit in his last months of living and let go of any fear or despair.

I emailed Griffiths in late September to see how he was doing and to share with him that I had been more committed to my meditation and was seeing real benefits in my life. He told me to stick with it — and I'm paraphrasing here — so you can see that thoughts, feelings and sensations come and go if you let them. Otherwise, they can limit who you think you are.

A few weeks later, Roland Griffiths died on October 16, at the age of 77.

I keep his medallion on my pile of rocks to remind me that impermanence is the natural state of things. And while we may not have a choice about when or how we leave this world, we get to choose how to live every day until that moment comes.

Here is our conversation from earlier this year.

This interview has been edited for length and clarity.

Rachel Martin: You started working a lot with psilocybin. Can you describe what that is in layman terms?

Roland Griffiths: It is a classic psychedelic drug. It comes from psilocybin-containing mushrooms and has been used for hundreds to thousands of years with indigenous cultures for ceremonial healings or sacramental religious experiences. It comes on fairly quickly and it doesn't last as long as LSD or mescaline, so it is easier to work with.

Martin: Do you use the expression "trips"?

Griffiths: No, I avoid that because it just has all of the baggage from the 1960s.

Martin: You were running these trials explicitly on cancer patients to see how the psilocybin would affect them.

Griffiths: That was our first therapeutic trial that we ran at Johns Hopkins with psychedelics. I remember feeling very cautious about what an experience of this sort would do to someone who's facing the most significant existential threat that they can.

As it turns out, the effects were nothing short of astonishing. This cohort of people, who met criteria for clinical depression or anxiety, after a single dose of psilocybin under our supported conditions, the anxiety and depression dropped markedly – immediately – and markedly and enduringly. That was the most important feature: We followed people up for six months and they remained with very low symptom profiles.

Martin: What did they say to you about how they lost a sense of fear or anxiety?

Griffiths: I do recall one man, I'm hesitant to give this example but I will, he came to believe in the reality of God. But what was so interesting is that this changed his whole frame of reference.

It wasn't that he was filled with spiritual language like, "God's gonna save me." No, it was an acceptance for his condition and a reassurance to the people he loved most, that everything was OK, everything was as it should be, and they felt uplifted by that.

Martin: If I may ask, why were you reluctant to share that example?

Griffiths: The God language.

Martin: We're all sort of limited by our language, right? Maybe some people use the word God because we don't know what other words to ascribe to these ideas or experiences.

Griffiths: I think that's precisely it. We live in the midst of this astonishing mystery. And we don't have a coherent scientific explanation of what's going on. The thing that we understand best about our experience of sentience, is that we are aware that we're aware. That we have an interiority, and it's only uniquely us as the individual that can affirm that.

Martin: You have found yourself on the other side of this whole thing as someone who is contemplating these very existential questions with new urgency.

Griffiths: Yeah, I went in for a screening colonoscopy, thinking myself to be completely healthy, and coming out with a stage four colon cancer diagnosis. And as unlikely as it seems, it has been a call to celebration. My wife and I have been in that mode in spite of multiple surgeries and chemotherapy.

Martin: Do you plan to take psilocybin at any point?

Griffiths: No. Initially, I actually didn't wanna touch a psychedelic, because I was worried it would alter the state I was in.

Martin: You didn't want to sabotage this mental clarity you had.

Griffiths: Yeah. Right. And so there came a point where I thought, I wonder if I'm defending against something here, I wonder if my reason for refusing to take a psychedelic is that I'm masking something. That there's a skeleton in my closet and I'm just saying I'm joyful and everything is beautiful.

So I decided, OK, so I'll take a dose of psychedelic. I took LSD.

Martin: How did it go?

Griffiths: Fantastic. I addressed the cancer as other, and in general I don't think it's wise to reify anything in mind as anything other than an object of mind. But in this case, I addressed the cancer itself and said, "OK, what's going on here?"

Cancer didn't answer. Then I got into a dialogue and said, "You know, I've considered you a blessing. I actually really respect everything that's occurred to me since this diagnosis. I'm truly grateful for the diagnosis, but do you have to kill me?"

Martin: Whoa. Was there an answer to that one?

Griffiths: Yeah, the answer was, "Yeah, you're going to die but this is as it should be. There's a deeper meaning. There's a deeper purpose. And you should continue to do what you're doing."

I felt implied in that was that I should speak out more broadly about what I was going through, because I've been reluctant to do so. So, I have something to say here. And so I asked, "How about giving me more time?"

Martin: I like that you went for the follow up.

Griffiths: I went for the follow up. But I got radio silence. It didn't answer. Was I dialoguing with cancer? No, that doesn't fit within my worldview. Some people would say I was, but it was deeply affirming to what I was doing and it felt like an empowerment to speak up.

My parting invitation is to celebrate. I'm inviting you to celebrate what I'm celebrating and that is this experience of the miracle of where we find ourselves. You need not have a terminal diagnosis to lean in more fully, and I promise you it's worth it.

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