How I Started to See Trees as Smart

First, I took an acid trip. Then I asked scientists about the power of altered states.

By Matthew Hutson The New Yorker

A couple of decades ago, on a backpacking trip in the Sierra Nevada, I was marching up a mountain solo under the influence of LSD. Halfway to the top, I took a break near a scrubby tree pushing up through the rocky soil. Gulping water and catching my breath, I admired both its beauty and its resilience. Its twisty, weathered branches had endured by wresting moisture and nutrients from seemingly unwelcoming terrain, solving a puzzle beyond my reckoning. I sensed a kind of wisdom in its conservation of resources. I imagined that the tree somehow wanted me to learn its lessons, to slow down and save my strength for the rest of the climb.

Later, when I told the story to a friend, she noted that I talked about sitting “with” the tree. I’d anthropomorphized it, making the tree sound like an elder or a friend. Given that I became an atheist at the age of ten, and that I always found more comfort in science than any kind of spirituality, these feelings amused me. I know that humans see intention or purposeful design in many places where it doesn’t exist. We see Jesus in pieces of toast, yell at our laptops, concoct conspiracy theories, and say that everything happens for a reason. Psychologists say that humans have “hyperactive agency detection”; psychedelic drugs probably turn up the knob.

Still, over the years, I found myself thinking about that tree. This past February, the American Association for the Advancement of Science hosted a session called Learning Without Neurons, which examined memory in slime molds, electrical circuits, and materials that learn to self-fold in various ways in response to forces. In “The Soul of an Octopus,” the naturalist Sy Montgomery compares scuba diving among sea creatures to taking LSD. “I find myself in an altered state of consciousness, where the focus, range, and clarity of perception are dramatically changed,” she writes. In an e-mail, Montgomery told me that, while diving, she feels as if “the mental experience of one species is no more real or valuable than any other.” When I wrote about the biologist Michael Levin, who studies electrical signals that instruct cells to become body parts, he told me, “I look for cognition everywhere. In some places you don’t find it, but I think I see it broader than many people.” Maybe it does make sense to consider a tree’s intelligence.

A couple of years ago, I came across Diverse Intelligences, an initiative of the Templeton World Charity Foundation that funds research projects with names like “Brainless Intelligence” and “Play, a Computational Perspective.” (T.W.C.F. shares its founder with—and has received donations from—the John Templeton Foundation, an unusual funder of science and spirituality research that has made some scientists uneasy. In the words of one critic, “Templeton plies its enormous wealth with a single aim: to give credibility to religion by blurring its well-demarcated border with science.”) The idea of intelligence without a brain can sound mystical or speculative, but the initiative has attracted quite a lot of human intelligence—including Levin, who has appeared as a guest speaker—so I was intrigued. I applied to attend an online gathering of the Diverse Intelligences Summer Institute, which brings together scientists, philosophers, and artists interested in all forms of cognition.

D.I.S.I. helped me recognize just how many people, scientists included, have sensed a kind of intelligence in life-forms that are not usually seen as conscious or smart: cells, slimes, animal swarms, plants. In conversations with participants, I was struck by how many of these perceptions occur to people in altered states, like my younger self on LSD. We can’t always trust what we perceive while our faculties are warped, whether through meditation or medication. But sometimes, my conversations suggested, we grasp new truths.

Sara Niksic, an artist and biologist, studies whale songs. She also swims and dives in the ocean. “I kind of zone out,” she told me. “I’m in this complete meditative state. Everything else just disappears.” Immersed in a medium that transmits sound for miles, she listens, and feels a connection with the animals around her. “When I’m down there, I can imagine how it would be to be this other species, and their cognition, how they see the world through sound.”

Few people would dispute the intelligence of nonhuman animals—just ask anyone who has ever lived with a pet—but altered states lead some to see intelligence in entire living systems. Termites are smart, but so are termite colonies, capable of building elaborate mounds. When Niksic dives, she thinks about the ways that oceans connect and support life around the world, almost like one big organism. Judit Mokos, an evolutionary biologist at Eotvos Lorand University, in Hungary, similarly perceives a kind of collective intelligence, a sense that different species are working together, during her solo trips to the forest. “You are calm, and pay attention to everything, every little detail, as everything could be important,” she told me by e-mail. “It’s like being in the belly of a huge animal, and not near individual creatures. You can just feel somehow that the whole forest is one.”

The experiences with altered states got weirder from there—and some of them made me think, again, of the tree. Monica Gagliano, an evolutionary ecologist whose research at Southern Cross University, in Australia, is supported by a million-dollar Templeton grant, has made the provocative argument that plants are conscious and intelligent. In her book “Thus Spoke the Plant,” she writes that drugs inspired her to look for unstudied capabilities in plants, such as the ability to remember or to communicate through sound. “If you are opening up yourself, there’s more space to allow for strange things to emerge,” she told me. “Isn’t this what scientists should be doing? Asking strange questions and seeing what they find?” During one shamanic ritual, she said, an ingested plant seemed to tell her about the design of a new experiment. She planted pea seedlings near a fan and a source of light; even when she moved the fan and removed the light, the seedlings seemed to remember where, in relation to the wind, the light had come from. (Her results were published in Scientific Reports.) Gagliano argued that many activities—meditation, yoga, gardening, or going for a walk in a national park—can spark similar kinds of insight.

Altered states might also make us aware of intelligences within us, according to a computer scientist at a prominent artificial-intelligence lab who enjoys LSD. “Being in altered states has made me realize, to a somewhat greater extent, that the brain is a bit of a kludge,” the scientist said. “It’s lots of different modules, sort of mashed together.” Some portions of our brains seem to play games in social settings—the scientist gave the examples of a “get-people-to-like-you game” and a “be-entertaining game”—and this may become obvious to a person who’s high. “I think of human intelligence as being messier than I thought it was,” the scientist told me, and added that artificial intelligence might need to be modular and messy, too.

Why might altered states lead us to see smarts around us? Given that we learn by finding patterns in the world, one possibility is that intelligence is a kind of pattern that we’re better off imagining than missing. The world actually is full of animacy and intention—notably, in other people. There is such a thing as intelligent design—how else would we get sidewalks, skyscrapers, and spaceships?—and some conspiracies are more than theories. “It is better for a hiker to mistake a boulder for a bear than to mistake a bear for a boulder,” the anthropologist Stewart Guthrie writes, in “Faces in the Clouds: A New Theory of Religion.” Likewise, it is better for a hiker to mistake a tree for a friend than to mistake a friend for a tree.

Maybe altered states crank up our search for patterns. In one study, published in 2014, researchers induced awe—one of the feelings associated with altered states—by showing participants videos of the documentary series “Planet Earth.” Awe made people less tolerant of uncertainty, which made them more likely to voice a belief in the supernatural or to perceive patterns in random strings of digits. In another study, published in 2018, participants who watched an awe-inspiring video were better at inventing novel uses for a cardboard box, compared with people who did not watch the video.

If there are times when humans underestimate other intelligences, altered states could counter that bias. I try to apply the concept of intelligence generously; some might dismiss trees as little more than pieces of wood, but I now see them as problem solvers. I can look at something that is clearly not sentient, such as a mountain stream, and think of the cascading and swirling water as the result of an algorithm more efficient than a human could design. Fluid follows gravity and the path of least resistance to lower ground, taking mind-bending turns along the way.

The cognition inside living creatures, crafted through billions of years of evolution, is cause for even greater inspiration. Consider the humble housefly. It can’t complete a human I.Q. test, but its nervous system processes its surroundings and orchestrates its movements far more quickly than my system can. In the game of survival, an insect’s reaction time easily beats my attempts to swat it. I may think of myself as the smartest creature in the room, but a fly can make me look foolish.