By Sarah Lynn Thomas
Co-CEO – Behold Retreats
For years, I have found myself talking about three broad traditions of medicine.
Most of us in the North understand what we mean by Western medicine. Many of us have also become familiar with Eastern medicine and practices such as meditation, acupuncture, yoga and Ayurveda.
But what about the South?
I have sometimes used the phrase Southern medicine to describe the ancestral, plant-based and earth-centered systems of healing I have encountered through our work with ayahuasca. At the World Ayahuasca Forum in Girona, Spain, I heard language that helped me become more precise: Indigenous medicine. Indigenous knowledge. Indigenous science.
That last phrase deserves attention.
Indigenous science challenges us to think more deeply about what we mean when we use the word science. For some Western ears, those two words may seem unusual together. We have been taught to associate science with laboratories, universities, peer review, controlled experiments and measurable data.
So when Indigenous knowledge keepers describe generations of observation of plants, human beings, consciousness, illness, nature and relationships as science, an important question arises:
Who decided what science is?
Indigenous Science: A Woman Standing in Two Worlds
That question was asked at the Forum by someone I found particularly compelling: Adana Omágua Kambeba.
Adana is an Indigenous leader of the Kambeba people of the Amazon and a Western-trained medical doctor. She has studied medicine within a university and hospital system while also undergoing years of traditional Indigenous training, including 6 years of dieta.
She spoke about trying to hold a dialogue between these two medicines within herself.
She knows what it is to be called into a hospital. She also knows what it is to return to Indigenous communities where knowledge and qualification are transmitted and evaluated through entirely different processes.
At the Forum, she raised three ideas that stayed with me:
Who decided what science is?
Our science does not need to be validated.
And perhaps most importantly:
Dialogue is not assimilation.
I had already been thinking about these questions before Girona, but hearing them expressed by someone who has studied and lived within both systems gave them new weight.
What would it mean for Indigenous science and Western science to enter into genuine dialogue—not so one can validate the other, and not so they eventually become the same, but so each can be understood more fully?
Indigenous Science and Western Science: Two Ways of Knowing
During the Forum, I found myself moving between what sometimes felt like two very different worlds.
In one room, researchers discussed EEG measurements, neuroplasticity, depression, biological mechanisms, DNA methylation and integration.
These are subjects Western science is extraordinarily equipped to investigate.
Elsewhere, Indigenous knowledge keepers spoke about plants, territory, ceremony, songs, visions, spirits, generations of apprenticeship, direct observation and relationships with the natural world.
Both were talking about ayahuasca.
But they were not necessarily asking the same questions.
They were not using the same methods.
And they were not always beginning from the same assumptions about what a human being is, what illness is, what healing is—or what constitutes evidence.
Rather than asking which worldview is correct, I found myself increasingly interested in the way in which we all participate.
A central message I heard from Indigenous leaders was a willingness to share their medicine and knowledge with the world.
So I found myself wondering: How can all of these different ways of knowing contribute to that journey, while respecting the knowledge and traditions the medicine comes from?
Indigenous Science and the Strengths of Western Science
I value Western medicine enormously. I have joked with some of my more alternative-minded friends that if I am ever in a terrible accident, please don’t call a Reiki practitioner first. I want a surgeon.
Western medicine has developed extraordinary capabilities. If I need someone to repair my heart, reconstruct my face after an accident, or treat a serious infection, I am deeply grateful for the knowledge, technology and skill it can offer.
But over the years, my joke has evolved.
Now I would say: I want the surgeon—and I want more.
I want the Western doctor with everything modern medicine has learned. I want the Eastern practitioner who may look at my body and health through a more holistic lens. And I want the Indigenous medicine practitioner whose understanding may include plants, spirit, community, nature and relationships that neither of the other systems was designed to see.
I don’t want one of these systems to replace the others. I want us to become better at recognizing what each knows how to do.
But every way of seeing also has a frame.
As ayahuasca enters Western research, we can measure brain activity, physiological responses, changes in psychological symptoms and many other things.
What happens when Indigenous practitioners tell us that other things matter too?
That ceremony matters.
That the songs matter.
That dieta matters.
That community matters.
That relationship with the plants matters.
That spirit matters.
These things are difficult to isolate, quantify or measure using the tools of contemporary Western science.
I don’t judge the blinders that can create, because we all have them.
My own understanding of ceremony, the role of the medicine man or woman, icaros, dieta and spirit has evolved enormously. Much of what I understand today was not part of my original worldview. It has developed through my own experiences in ceremony, through the ceremonies I have been in service to, and through countless hours of listening to and learning from our medicine teams, friends and wisdom keepers.
I can see more today because other people helped me see what I could not see before.
And perhaps that is one of the greatest values of a gathering like the World Ayahuasca Forum: bringing people with very different ways of knowing into the same room—not simply to present their work, but to encounter one another’s questions.
I watched this happen during one scientific session. Five researchers presented their work on ayahuasca from different areas of Western research. During the Q&A, someone in the audience observed that across the presentations, Indigenous people and Indigenous knowledge had not entered the conversation. The attendee then asked a question that challenged the researchers to consider that absence.
There wasn’t an easy answer.
And perhaps there didn’t need to be one.
What interested me was the question itself. A researcher may spend years becoming exceptionally skilled at looking through one particular lens. Then someone enters the room and asks about something that lens has not been designed to see.
I don’t know what those researchers thought afterward or whether the question will influence their future work. But I know what questions like that have done for me.
They have helped me notice my own blinders.
That is what dialogue can offer. Not necessarily an immediate answer, and not necessarily agreement, but the possibility that after encountering another way of seeing, we return to our own work asking a question we weren’t asking before.
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Research as a Bridge, Not a Gatekeeper
Months before the Forum, during a podcast conversation, I was asked about the importance of Western science validating these medicines.
The question stayed with me because I realized I saw it differently.
The communities that have worked with these medicines across generations do not need a Western laboratory to tell them that their medicines have value. They already have their own bodies of knowledge, observation, practice and experience.
The validation is often something we in the West need.
And I understand why.
We speak different languages of evidence.
If you were raised within Western systems, scientific research can provide a framework that feels familiar. It can help people understand potential benefits and risks. It can give physicians, universities and institutions information they know how to evaluate.
That makes Western research enormously valuable.
Research should be a bridge, not a gatekeeper.
Western science can help translate aspects of Indigenous knowledge into a language that Western societies understand.
But translation is not the same as validation.
One knowledge system does not become real only when another knowledge system learns how to measure it.
This distinction became particularly meaningful at the Forum.
We heard from Indigenous representatives whose communities have experienced generations of suppression, misunderstanding and, in some cases, persecution surrounding their traditional medicines.
Sewa María García Valenzuela shared the story of her own family and community in Mexico, where traditional practices were suppressed and demonized through colonization. She later made the deliberate choice to invite scientists and researchers into her community.
I found the complexity of that choice deeply moving.
The knowledge of her community had not suddenly become true because researchers arrived. Rather, she recognized that research could help communicate with the very institutions and systems that had historically misunderstood their practices. Western science could provide another language—one that Western institutions might be more willing to hear.
There is an important paradox here.
Western research can be profoundly useful in helping Western societies reconsider practices they have historically misunderstood.
But there is another tension here.
If, in order to study ayahuasca, we remove the medicine from the ceremony, the songs, the medicine keeper, the community, the preparation, the relationship with the plants and the knowledge system from which it came, what exactly are we studying?
We may learn something valuable about a molecule, a physiological response, or what happens when ayahuasca is administered in a controlled environment.
But are we still studying the same medicine?
For me, this is where research itself can risk becoming another form of extraction: taking the part that fits within our own system of understanding while leaving behind the wisdom and relationships that have traditionally surrounded it.
That does not make the resulting research meaningless. But it should make us careful about what conclusions we draw from it, and about what we believe that research gives us permission to recreate.
So perhaps before we ask what the research shows, we should ask:
What is the purpose of the research?
Are we gathering evidence that may help inform legal and regulatory conversations, including the ability of Indigenous medicine keepers to travel with and practice their traditions across borders?
Are we developing research that can help organizations like ours communicate with Western guests who feel called to these medicines but want to understand them first through a framework that is familiar to them?
Are we studying ayahuasca in a one-on-one clinical setting to understand its potential effects on depression or anxiety? And if so, is the purpose to increase interest in the traditional contexts or to perhaps develop clinical models?
Or are we conducting research to “validate Indigenous medicine”?
Because if it is one of the last two, I think we need to ask more questions:
Are we validating Indigenous medicine, or are we making it more understandable to the Western mind?
Those are not the same thing.
And perhaps there is another question underneath all of them:
How do we study the medicine without extracting it from the knowledge system and wisdom keepers that taught us it was medicine in the first place?
And this is something I deeply appreciated about the World Ayahuasca Forum. It didn’t simply create a stage for people to present their work; it created a space for different ways of knowing to meet, question one another, and perhaps expand the work itself.
We may not leave with all the answers. But we may leave asking better questions.
What Happens When We Reverse the Questions?
One discussion at the Forum offered a thought experiment that stayed with me.
Western institutions have developed a growing body of research around psychedelics, including important work with psilocybin. Now medicines such as ayahuasca—medicines carried within living Indigenous traditions—are also entering Western laboratories and being evaluated through Western scientific methodologies.
This creates an unusual dynamic: one knowledge system becomes responsible for determining which elements of another can be demonstrated according to its own standards of evidence.
But imagine reversing the relationship.
Imagine taking the knowledge of a Western cardiologist and saying:
We are willing to investigate your medicine, but we will evaluate it exclusively through our own knowledge system.
We will accept the parts that can be understood through plant relationships, visions, ceremonial practice, oral knowledge and generations of community observation.
Everything else will remain unproven.
A Western physician would reasonably object:
You are evaluating my entire knowledge system using tools that were never designed to understand it.
And then comes the uncomfortable question:
Might Indigenous knowledge holders sometimes feel the same way when Western institutions evaluate their sciences exclusively through Western methodologies?
I suspect many do.
This does not mean every claim made within any traditional knowledge system should automatically be accepted as scientific fact.
Nor does it mean Western science should abandon the rigor that makes it so valuable.
It means we should remain conscious of the authority we may give Western research, especially when we don’t know what may be missing from the perspective of Indigenous medicine keepers.
Perhaps the goal is not to lower the standards of either system, but to become more aware of whose standards we are using, and what those standards may allow us to see or prevent us from seeing.
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Dialogue Is Not Assimilation
This is why Adana’s words stayed with me:
Dialogue is not assimilation.
The goal does not have to be turning Indigenous science into Western science.
Nor should the goal be rejecting Western science in favor of Indigenous knowledge.
The Forum deliberately created spaces where Indigenous knowledge holders, researchers, clinicians and academics could enter into conversation about how different systems of knowledge might learn from one another.
That requires something more difficult than simply agreeing.
It requires allowing difference to remain.
Western science may ask: What is happening in the brain?
Indigenous science may ask: What is happening in the person’s relationship with themselves/their inner world, nature, the community, or the spiritual world?
A therapist may ask: How does this experience affect the person’s emotional life?
A traditional healer may ask questions that do not translate neatly into any of those frameworks.
Perhaps the opportunity is not to decide which question is the correct one.
Perhaps it is to notice how much more we can see when more than one question is allowed to exist.
Expanding Our Understanding of Indigenous Science
One of the sessions at the Forum was titled “Recognizing Indigenous Sciences as the Bridge Between Worlds.”
Even the plural is meaningful.
Sciences.
Not one Indigenous worldview. Not one Western worldview. Not one universal system capable of explaining everything.
Different cultures have spent generations observing nature, plants, bodies, relationships, consciousness and the conditions under which human beings flourish or suffer.
Their methods of observation, transmission and verification may be different.
Their languages may be different.
Their assumptions about nature and consciousness may be different.
Difference does not mean inferiority.
And respect does not require romanticizing any knowledge system as infallible.
For me, this is where humility becomes essential.
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Keeping My Own Door Open
I have never believed Western science and Indigenous sciences need to become one. Different systems can ask different questions, use different methods and illuminate different dimensions of our experience.
The challenge is learning how to let them meet without requiring one to disappear inside the other.
And that was one of the things I appreciated most about the World Ayahuasca Forum. It created a place for these conversations to happen—for different people to share what they know, ask difficult questions, listen to one another, and practice respect even when they do not see the world in the same way.
And perhaps that begins with something much more personal.
I have to remain aware of my own blinders.
I was educated within a culture that taught me certain ways of knowing were science, and others were belief. Certain kinds of evidence were objective and others subjective. Certain knowledge required proof, while the assumptions underneath my own worldview often went unquestioned.
My work with Indigenous medicine has asked me to become more aware of those assumptions.
Some of the ways of knowing I grew up with remain deeply valuable to me. Others I have questioned, changed, or abandoned altogether.
I consider myself a seeker of knowledge in many forms. That means questioning what I encounter, but it also means questioning myself—my beliefs, my assumptions, my conditioning, and the frameworks through which I interpret the world.
At the Forum, I was deeply moved listening to men and women speak about nature, water, land, forest, sun and spirit not as separate subjects, but as parts of an interconnected living system.
That relationship with nature was not part of my own upbringing in the same way.
Today, it has become part of my practice.
And perhaps that is another form of learning: not simply accumulating new information, but becoming willing to see something our previous framework may not have taught us to notice—and sometimes being willing to change because of what we see.
The World Ayahuasca Forum did not give me a new definition of science.
It gave me a better question:
What if our understanding of science becomes larger when we stop requiring all knowledge to arrive through the same door?
For me, the practice is to keep that door open—to remain curious, conscious of what I may not see, willing to question what I think I know, and humble enough to keep listening.
