What exactly is consciousness? (And does my venus flytrap have it too?)

by and bowlsHarvard Gazette

The brain constantly handles countless bodily functions, and most of them happen without us being aware of it. So why do some operations rise to the level of awareness?

That’s the question at the heart of Michael Pollan’s just-released new book, “A World Appears: A Journey Into Consciousness.”

Pollan is the award-winning author of 10 books, including “This Is Your Mind on Plants” and “How to Change Your Mind,” and he is the Lewis K. Chan is Lecturer in Arts and Professor of Nonfiction Practice, Emeritus. His latest book takes insights from science, literature, philosophy, spirituality and psychedelics to turn the spotlight on consciousness itself and explore what it is — and whether it’s only human.

Pollan will do Discuss the book with Louisa Thomas, a staff writer for The New Yorker and a lecturer in creative writing at Harvard University, Thursday at First Parish Church in Cambridge.

This interview has been edited for length and clarity.

You begin by defining the “hard problem” of consciousness that the book sets out to explore. What is that hard problem?

It was set out in 1994 by a philosopher named David Chalmers, and he basically said, “How do you go from matter to mind? How do you go from three pounds of brain tissue to subjective experience, having a voice in your head? You don’t know about 90 percent of what the brain does, so why is this part of our brain completely automated?”

This is a problem that neuroscientists have been working on since the late 80s. Prior to this, consciousness was not considered a respectable topic for scientists, so little work was done.

So the book is really an overview of modern attempts to understand consciousness by both scientists and other kinds of thinkers.

There are many theories about what consciousness is, and Chalmers is a sort of key figure in judging the relative success of each.

Yes, he is very good at it. He takes any new theory of consciousness and applies himself to it until he hits a wall. He serves the field as a sort of superego.

But a surprising number of scientists see him as an arbiter of what is a good theory or not. It’s an interesting phenomenon, because you don’t usually have science suspended in philosophy, but this is one area where it happens.

Why do you think so?

It is possible that we do not have the right kind of science to solve this particular problem. We must understand consciousness as consciousness: the entire scientific enterprise is an expression of human consciousness. We can never step outside of it, and that makes it a uniquely difficult problem.

Also, for the past 400 years, science has organized itself around the idea that it should focus on objective, measurable, quantifiable reality and leave content to the church. That was Galileo’s bargain, and it still holds.

Ultimately the tools we have to understand what a subjective experience is are limited, and I would argue that it may take a revolution in science to solve the problem. Science may need to learn how to incorporate phenomenology – lived experience – into its approach before we can solve this problem.

That doesn’t mean we can’t learn a lot about consciousness. We are all experts at this. Novelists and poets also know a lot about consciousness, so I turn to them as well as scientists.

What are we really talking about when we talk about consciousness?

In the book I move from the senses to the simplest to the most complex manifestations of consciousness. There are those who would say consciousness and feeling are the same thing, but I see an important difference.

I think sensation is a simpler, more basic form of consciousness. All it requires is an awareness of one’s environment, the ability to distinguish beneficial changes from destructive ones, and to move toward one and away from the other. Even bacteria have it: chemotaxis is the ability of bacteria to detect dangerous molecules and food.

I think sensation might be a property of life that you have to deal with in a world that’s complex and ever-changing and unpredictable, and it might be that every living thing senses in a different way according to their needs, at the scale they live in.

A group of researchers who call themselves plant neurobiologists (it’s not exactly neurobiology, since no neurons are involved; I think the name is meant to troll the more conventional botanists) are doing fascinating experiments that show, for example, that plants can be made unnerved.

If you expose a Venus flytrap to xenon gas, which is a strange type of anesthetic, they won’t react when a fly crosses their threshold. Another plant, Mimosa pudica, can be taught not to respond to false stimuli, not to drop its leaves. It can remember lessons for 28 days.

Also, a corn plant root can navigate a maze to find fertilizer. There are some vines that change the shape of their leaves depending on which tree they are curling around.

I will not tell that consciousness. I don’t think trees have interiority the way we do. But there is more to plants than instinct. They are capable of making wise decisions.

You go on to talk about feelings as this next level of consciousness. Why do feelings play such a large role in the structure of your consciousness?

For a long time, scientists assumed that consciousness must be a cortical phenomenon. It had to be tied to rational thought, the kind of thing only we humans can do.

But a neuroscientist named Antonio Damasio, beginning with his book “Descartes’ Error,” showed that feelings come first, that consciousness may be a product of the upper brain, not the cortex. I think he makes a persuasive case.

Let’s say you have a feeling of hunger. It’s a basic sensation built into your body, and your cortex is enlisted to make a reservation for dinner or imagine the various counterfactuals you might be fed. So the cortex is involved, but it comes into the picture later.

If you believe that feelings are the basis of consciousness, this has several implications. One is that it helps that animals, which have similar structures in the brain stem, are conscious. Another underlying question is whether machines can be conscious. Machines are pretty good at thinking, but they’re much less good at feeling.

Emotions are based in biology; Feelings are how the body communicates with the brain. And the feeling depends, I think, on the fact that we can suffer, perhaps on the fact that we are mortal. You can ignore a feeling completely if it isn’t accompanied by a sense of vulnerability.

So I’m not sure that computation can describe everything in the brain. Our thought processes are so subtle and subtle, it’s hard to account for calculations.

What did you learn about your own thought process by writing the book?

Scientists rarely look at the content of consciousness, which is our thoughts. But I’ve worked with a psychologist named Russell Hurlburt, who for the past 50 years has modeled what he calls inner experience.

If you participate in his experiment, as I did, you wear a beeper, and during the day, at completely random times, it beeps in your ear, and you have to write down exactly what you were thinking at that moment, no matter how simple or profound. (In my case, it was always normal.)

And then he interrogated you. He said, “Were you thinking in words, images, or symbolless thoughts?” If you were thinking the words, were you saying them or hearing them? He really drills down.

In my case, he concluded that I had very little inner experience. I was offended by this, because I think I have a lot of inner experience, but he didn’t find it.

50 years later, his biggest discovery is that we don’t know much about how we think, and that different people think in different ways.

At certain times of reading the book, I became so interested in analyzing my own thoughts that I stumbled upon the act of reading.

Yes! One of the things I’m trying to do is defamiliarize consciousness. You know, my experience with psychedelics is partly what got me interested in consciousness, as have millions of other people who have used them.

Going through life, reality seems transparent to us. We forget we are looking through the window of our consciousness. But it takes consciousness to show the world to us.

Psychedelics kind of stain the window pane so we can be aware of this miracle. I’m hoping the book will do the same, without any chemical help.

Ultimately, I shift from focusing on the problem of consciousness to its wonderful truth. We’ve been given this gift of consciousness, and we mindlessly give it away to companies that want to profit from it — buying and selling our attention and, with AI, our emotional attachment.

I’m hoping people walk away with the sense that this is really precious, this space of privacy and freedom that we have and we need to protect it.

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This story is reprinted from permission from Harvard Gazette.