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Gaia hypothesis

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Gaia hypothesis , model of the Earth in which its living and nonliving parts are viewed as a complex interacting system that can be thought of as a single organism. Developed c. 1972 largely by British chemist James E. Lovelock and U.S. biologist Lynn Margulis , the Gaia hypothesis is named for the Greek Earth goddess. It postulates that all living things have a regulatory effect on the Earth’s environment that promotes life overall; the Earth is homeostatic in support of life-sustaining conditions. The theory is highly controversial.

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• Published: 08 March 1990

Hands up for the Gaia hypothesis

• James E. Lovelock 1  

Nature volume  344 ,  pages 100–102 ( 1990 ) Cite this article

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The concept of Gaia, a self-regulating Earth, excites both admiration and obloquy. Its inventor (or rather re-discoverer) describes the genesis and evolution of the hypothesis.

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Lovelock, J. Hands up for the Gaia hypothesis. Nature 344 , 100–102 (1990). https://doi.org/10.1038/344100a0

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Imagining Gaia, the Earth, as ‘one great, living organism’

James Lovelock’s hypothesis could unlock a whole-systems approach to protecting the amazing life forms on Earth.

• By Steve Curwood

The Gaia hypothesis, devised by James Lovelock, posits that Earth is a living, self-regulating organism.

Over 50 years ago, scientist James Lovelock hit upon the idea that Earth is a complex, self-regulating organism. At the suggestion of a friend, novelist William Golding, he called his idea the Gaia hypothesis, after the Greek goddess who symbolizes Earth.

Simply put, the Gaia hypothesis says that Earth is a living system and uses similar mechanisms that living creatures use to stay alive, by constantly regulating temperature, chemical and physical inputs and outputs and adaptation through evolution.

Lovelock, who turned 101 in 2021, came up with his idea in the 1960s, when NASA asked him to see if his inventions in chemical analysis could detect life on other planets by looking at their atmospheres.

Venus, our nearest neighbor at 25 million miles closer to the Sun than Earth, is literally a hot mess, with steady surface temperatures of nearly 900 degrees Fahrenheit and an atmosphere of mostly carbon dioxide laced with bits of sulfur droplets — not hospitable for life forms we know.

Mars, 100 million miles further from the Sun than Earth, is a bit less hostile to life, with days of searing heat and nights of deep cold. It also has an atmosphere overwhelmingly made up of carbon dioxide, with just tiny traces of oxygen.

Lovelock’s insight came when he realized that the bigger question was not, “Is there life on those other planets?” but rather, “Why is there life here on Earth?”

Like Venus and Mars, Earth has strong volcanos that, over time, have spewed out huge amounts of carbon dioxide. These volcanos should have created a hothouse or a desert on Earth. But something has kept carbon dioxide levels in a sweet spot: just four hundredths of a percent of the Earth’s atmosphere, enough to keep it warm, but not too warm, for life, while the oxygen needed for animals is in great abundance — and that something is life itself.

About a billion years after Earth was formed, photosynthesis evolved. Photosynthesis is how plants, algae and other organisms convert sunlight into chemical energy and break down CO2 into its elements, carbon and oxygen. Over millions of years, plants and algae sequestered in their cells all that carbon from volcanos, and when buried in the ground or under the sea, some of it eventually became coal and oil.

Four times in Earth’s geologic history, giant eruptions of volcanoes belched out so much CO2 they set off mass extinctions. A separate mass extinction was linked to an asteroid strike that likely shut down a lot of Earth’s photosynthesis and allowed CO2 levels to rise.

After each of these cataclysmic events, Earth had to start sequestering carbon again, as life evolved to adapt to new conditions. So, when we drill and dig up fossil fuels today, we are upsetting a balance the Earth works hard to keep. But if we keep those fossil fuels in the ground, we help support the living planet.

Many scientists have helped advance the Gaia hypothesis — now known as Gaia theory — over time. One of the most public voices is Stephan Harding, a former student of James Lovelock. Harding is now a deep ecology research fellow at Schumacher College in England.

In sum, he says, every living plant and animal on Earth interacts with nonliving rocks, atmosphere and water to make the planet an independent, living organism.

“It’s the ability of the whole, of all four of them working together — life, atmosphere, rocks and water — working together to keep the surface conditions on the planet suitable or within the limits that life can tolerate. ” Stephan Harding, deep ecology research fellow, Schumacher College 

“The scientific idea is that when they start interacting with each other, these four components, something extraordinary emerges out of those interactions which you couldn’t have known in advance. It’s called an emergent property,” Harding explains. “It’s the ability of the whole, of all four of them working together — life, atmosphere, rocks and water — working together to keep the surface conditions on the planet suitable or within the limits that life can tolerate.  Life has a very important role here. Life is intimately involved in regulating the temperature, the acidity of the planet, the distribution of key elements. And so, the idea suggests that the Earth is one great living organism. “ 

And as thinking about Gaia has evolved, more credence has been given to the notion that not just biologically active beings, but also the so-called inanimate things like rocks and water, can support life. Observations reveal countless examples of the ways in which life, in its many forms, regulate the planet.

“So just think of that: Living beings are actually helping to cool the surface of the planet. I  mean, that’s amazing .” Stephan Harding, deep ecology research fellow, Schumacher College 

“Basically, we now know that many kinds of organisms, including marine algae and forests, like rain forests,…emit chemicals that seed clouds,” Harding says. “And those clouds are dense and white and they  cool  the Earth. And this is happening over  the rain forests and over parts of the ocean. So just think of that: Living beings are actually helping to cool the surface of the planet. I  mean, that’s amazing .”

Harding says scientists are pretty sure they understand how  Gaia  has regulated temperature over geological time. Volcanoes continually emit carbon dioxide into the atmosphere while, simultaneously, the sun grew brighter — about 30% brighter now than it was when life began on Earth about 4 billion years ago.

These two conditions — increasing CO2 in the atmosphere and the increasing brightness of the sun — are “a recipe for an absolute disaster for life,” Harding says. “Eventually the planet will get so hot…all the water would evaporate — boil off, like in a kettle. It’s called a runaway  greenhouse. That’s what happened on Venus. But it didn’t happen on Earth because of life — because of life interacting, holding the water down, capturing the hydrogen as it was trying to flee.”   

Today, some people dismiss the Gaia hypothesis and the role of rocks and water in life as a pseudo-intellectual exercise that seeks to put a more acceptable face on animistic beliefs of aboriginal societies. But Stephan Harding believes we are all born with an intrinsic understanding of Gaia.     

“It’s just our natural humanity to feel the Earth as alive and as a mother. It’s built into us,” he says.

Yet modernity, he says, is headed for extinction because of the way we currently relate to Gaia.

“We don’t relate to Gaia with our aboriginality; we relate to her through our greed and our desire for more stuff and more money and more prestige, and our competitive urges are just over-exaggerated. [A] culture like that will go extinct.”

If modern humans don’t change our ways to find harmony with the Earth, Gaia will do it for us. 

“We’ve pushed nature back, we’ve  destroyed her to such an extent that there have to be very powerful feedbacks to control this species, the species of modernity.” Stephan Harding, deep ecology research fellow, Schumacher College 

“That’s a classic  Gaian feedback,” Harding says. “We’ve pushed nature back, we’ve  destroyed her to such an extent that there have to be very powerful feedbacks to control this species, the species of modernity. I won’t say humans because humans are wonderful. It’s modernity that’s the problem. I’ve come to that conclusion. Modernity, this modern way of life, it’s a big problem. And it’s evoking these feedbacks from Gaia. The coronavirus is just the start. If we don’t do anything about greenhouse gases and the destruction of biodiversity, which helps us control greenhouse gases, amongst other things, we haven’t got much hope, really, not in the long-term. That’s the science.” 

Perhaps the most powerful observations of Gaia come from people who have seen Earth from outer space, including retired NASA astronaut Ron Garan, who flew in the space shuttle and got to take a spacewalk.

“I had, obviously, never seen the Earth from that vantage point,” he says. “And I thought about that, when we…look at the Grand Canyon…when we sit on a beach at sunset and look at a beautiful sunset, gravity is pushing us into that scene. We’re inside the frame of the masterpiece, we’re part of that painting, if you will. But for the first time in my life, I was seeing this exquisite beauty from the outside. And somehow that outsider perspective — what I call the orbital perspective — compelled me to feel deeply interconnected with everybody and everything on the planet.”

Garan says the name Gaia is fine but he balks at the word hypothesis.  

“I don’t think it’s a hypothesis, I think it’s obvious,” he says.

“Seeing the planet from that vantage point of space makes it obvious that we’re looking at a living, breathing organism, a multicelled organism, an organism that has different aspects of it, based on the various, multivaried species of life that exists upon the surface and below the surface of Earth and in the atmosphere of Earth. And all of those different species, different individual animals and plants are all part of an implicit wholeness that is the planet itself. It’s all not only interconnected, it’s deeply, deeply interdependent.”

This article is based on an audio essay that aired on Living on Earth from PRX.

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The perceptual implications of gaia.

The Gaia hypothesis represents a unique moment in scientific thought: the first glimpse, from within the domain of pure and precise science, that this planet might best be described as a coherent, living entity. The hypothesis itself arose in an attempt to make sense of certain anomalous aspects of the Earth’s atmosphere. It suggests that the actual stability of the atmosphere, given a chemical composition very far from equilibrium, can best be understood by assuming that the atmosphere is actively and sensitively maintained by the animals, plants, oceans, and soils all acting collectively, as a vast, planetary metabolism. In James Lovelock’s own words, the hypothesis states that:

The entire range of living matter on Earth, from whales to viruses, and from oaks to algae, could be regarded as constituting a single living entity, capable of manipulating the Earth’s atmosphere to suit its overall needs and endowed with faculties and powers far beyond those of its constituent parts. [1]

It is gratifying to see that this hypothesis is slowly gaining a hearing in the scientific world, while being further substantiated by biologist Lynn Margulis, whose meticulous research on microbial evolution has already shown the existence of certain Gaian regulatory systems. [2] That the hypothesis will gain proponents only slowly is to be expected, for to accept it as valid is to throw into question many deeply ingrained scientific and cultural assumptions. In fact, the recognition of Gaia has powerful implications for virtually every realm of scientific and philosophical endeavor, since it calls for a new way of perceiving our world. In this essay I will explore just a few implications that the Gaia hypothesis holds for our understanding of perception itself.

OUR IMMERSION IN GAIA

It is significant that the first evidence that the surface of this planet functions as a living entity should come from a study of the atmosphere, the very aspect of the Earth that we most commonly forget. The air is so close to us that we tend to leave it out of our thinking entirely — much as we do not often attend to the experience of breathing, an act so essential to our existence that we take it completely for granted. The air that surrounds us is invisible to our eyes; doubtless this has something to do with why we usually act and speak as though there were nothing there. We refer to the space between things, or the space between two people; we do not speak of the air between us, or the air between oneself or a nearby tree. We generally assume, unless we stop to think about it, that the space between us is roughly continuous with the space between planets.

This is attested by our everyday language — we say that we dwell on the Earth, not that we live within the Earth. Yet if the Gaia hypothesis is correct, we shall have to admit that we live in this planet rather than on it. In direct contradiction to the earlier scientific assumption that life on Earth’s surface is surrounded by and adapts to an essentially random environment, Gaia indicates that the atmosphere in which we live and think is itself a dynamic extension of the planetary surface, a functioning organ of the Earth.

It may be that the new emphasis it places on the atmosphere of the world is the most radical aspect of the Gaia hypothesis. For it carries the implication that before we as individuals can begin to recognize the Earth as a self-sustaining organic presence, we must remember and reacquaint ourselves with the very medium within which we move. The air can no longer be considered a merely negative presence, an absence of solid things: henceforth the air is itself a density — mysterious, indeed, for its invisibility, but a thick and tactile presence nonetheless. We are immersed in its depths as surely as fish are immersed in the sea. It is the Medium, the silent interlocutor of all our musings and moods. We simply cannot exist without its support and nourishment, without its vital participation in whatever we are up to at any moment.

In concert with other animals, with the plants, and with the microbes themselves, we are an active part of the Earth’s atmosphere, constantly circulating the breath of this planet through our bodies and brains, exchanging certain vital gases for others, and thus monitoring and maintaining the delicate makeup of the medium. As Lovelock has indicated, the methane produced by the microorganisms that make their home in our digestive tracts — the gas we produce in our guts — may conceivably be one of our essential contributions to the dynamic stability of the atmosphere (less important, to be sure, than the methane contribution of ruminant animals, but essential nonetheless). Small wonder that we of literate culture continue to forget the air, this ubiquitous presence, for we prefer to think of ourselves serving a loftier purpose, set apart from the rest of creation. Our creativity, we assume, resides not in the depths of our flesh but in some elevated realm of pure thoughts and ideas that stands somehow outside the organic. [3]

Yet it is only by remembering the air that we may recover our place in the actual world that we inhabit. For the air is the invisible presence, so little understood, that materially involves us in the internal life of all we see when we step out of doors, in the hawks and trees, in the soil and the sea and the clouds. Let us return to this point later. For now it is enough to discern that the Gaia hypothesis implicates the enveloping atmosphere as a functioning part of the overall system. Thus, if we choose to view this planet as a coherent, self-sensing, autopoietic entity, we shall have to admit that we are, ourselves, circumscribed by this entity. If Gaia exists, then we are inside her.

GAIA AND PERCEPTION

The consequences for our understanding of perception and the function of the human senses are important and far-reaching. Traditionally, perception has been taken to be a strictly a one-way process whereby value-free data from the surrounding environment is collected and organized by the human organism. Just as biologists had until recently assumed, for simplicity’s sake, that life adapts to an essential random environment, [4]   so psychologists have assumed that the senses are passive mechanisms adapted to an environment of random, chance events. The interior human “mind” or “subject” is kept apprised of these random happenings in the exterior “objective” world by the sense organs, mechanical structures that register whatever discrete bits of sensory data — light, sound, pressure — they come into contact with, and transfer these separate bits of information into the nervous system. Here these separate sensations are built up, step by step, into a representation of the external world. It is this internal representation that is ultimately viewed and given meaning by the innermost “mind” of the perceiver.

Such is the classic model of perception propounded by Descartes, Locke, and Berkeley in the seventeenth century, and later formalized by the founders of modern scientific psychology. [5]   Although it has undergone many revisions and qualifications, this account still underlies most of the scientific discourse of our time. Within this account, meaning and value are assumed to be secondary, derivative phenomena resulting from the internal association of external facts that have no meaning in themselves. The external world is tacitly assumed to be a collection of purely objective, random things entirely lacking in value or meaning until organized by the ineffable human mind.

If this sounds like the assumption behind the agenda of to-day’s “value-free” sciences, we should note that each of the natural sciences completely depends, at some level, upon the exercise of human perception for the accumulation of its data — whether through a microscope, a telescope, or even the keyboard and screen of a computer. Yet none of the separate sciences have ever come up with an alternative description of perception that could supplant the traditional account. (Even quantum physicists, who have long recognized the untenability of this description of perception with regard to the subatomic domain, have proposed no substantial alternative.)

Each of the contemporary sciences, then, must still pay lip service to a model of perception constructed in accordance with eighteenth-century notions of the mechanical nature of the physical world and the absolute separation of mind from matter. One important reason for our prolonged adherence to an obsolete model may be the fact that, although it does not describe perception as we actually experience it, this model does describe perception as we need to conceive it if we are to continue in our cultural program of natural manipulation and environmental spoilage without hindrance of ethical restraint. The traditional account of perception as a unidirectional mechanical process is the only account possible if we still assert the convenient separation of psyche, subjectivity, or self-organization from the material world that surrounds us.

The Gaia hypothesis immediately suggests an alternative view of perception. For by explicitly showing that self-organization is a property of the surrounding biosphere, Gaia shifts the locus of creativity from the human intellect to the enveloping world itself. The creation of meaning, value, and purpose is no longer accomplished by a ghostly subject hovering inside the human physiology. For these things — value, purpose, meaning — already abound in the surrounding landscape. The organic world is now filled with its own meanings, its own syntheses and creative transformations. The cacophony of weeds growing in an “empty” lot is now recognized for its essential, almost intelligent role in the planetary homeostasis, and now even a mudflat has its own mysteries akin to those of the human organism. [6]

We are beginning to glimpse something of the uncanny coherence of enveloping nature, a secret meaningfulness too often obscured by our abstractions. This wild proliferation is not a random chaos but a coherent community of forms, an expressive universe that moves according to a diverse logic very different from that logic we attempt to impose.

But if, following the Gaia hypothesis, we can no longer define perception as the intake of disparate information from a mute and random environment, what then can we say that perception is?

The answer is surprisingly simple: Perception is communication. It is the constant, ongoing communication between this organism that I am and the vast organic entity of which I am a part. In more classical terms, perception is the experience of communication between the individual microcosm and the planetary macrocosm.

Let us think about this for a moment. If the perceivable environment is not simply a collection of separable structures and accidental events; if, rather, the whole of this environment taken together with myself constitutes a coherent living Being “endowed with faculties and powers far beyond those of its constituent parts,” [7]   then everything I see, and everything I hear, is bringing me information regarding the internal state of another living entity — the planet itself. Or rather about an entity that is both other and not-other, for as we have seen, I am entirely circumscribed by this entity, and am, indeed, one of its constituent parts. Perhaps it is misleading, then, to use the term “communication” to describe a situation in which one of the communicants is entirely a part of the other.

The word communication, so often associated with a purely linguistic interchange, has overtones of something rather more conscious and willful than what we are trying to describe. Here we are referring to an exchange far more primordial, and far more constant, than that verbal exchange we carry on among ourselves. What is important is that we describe it as an exchange, no longer a one-way transfer of random data from an inert world into the human mind, but a reciprocal interaction between two living presences — between my own sentient body and the vast, spherical Body of the biosphere. Perhaps the term communion is more precise than communication. For by communion we refer to a deeper mode of communication, more corporeal than intellectual: a sort of sensuous immersion, a communication without words.

Perception, then — the whole play of the senses — is a constant communion between ourselves and the living world that encompasses us.

Such a description of perception, as a reciprocal phenomenon organized as much by the surrounding world as by oneself, is not entirely new to contemporary psychology. Indeed, recent developments in the study of perception indicate that sooner or later it must be reconceptualized as an interactive phenomenon.

For example, research on the evolutionary development of perceptual systems in various species suggests that these systems simply cannot be understood in isolation from the communication systems of those species. [8]  And at least two of the most important twentieth century investigators working (independently of each other) on the psychology of human perception — Maurice Merleau-Ponty in Europe and James J. Gibson in the United States — had already begun, decades ago, to speak of the surrounding physical world as an active participant in our perceptual experience.

J.J. GIBSON AND DIRECT PERCEPTION

James J. Gibson published his text The Perception of the Visual World in 1950 and followed it with The Senses Considered as Per ceptual Systems in 1966 and The Ecological Approach to Visual Perception in 1979. [9]   In these books Gibson challenged the traditional account of perception which, as I indicated above, describes perception as an internal process whereby an initially meaningless mass of sensory data (resulting, say, from the impingement of photons on the retinal nerve cells) is built up into an “internal representation” of the external world.

This account, true to its Cartesian foundations, assumes a fundamental disjunction between the psychological (human) perceiver, described ultimately in mentalistic terms, and the purely passive environment, described in terms borrowed from physics. Gibson called this entire paradigm into question by asserting that perception must be studied as an attribute of an organism and its environment taken together. He showed that if we assume a natural compatibility between an animal and its earthly surroundings — what he and his followers refer to as an “animal-environment synergy” — then perception is recognized not as an indirect process carried on inside the organism but as a direct exchange between the organism and its world.

Gibson felt that artificial laboratory situations had misled psychologists into conceptualizing perception as a physically passive, internal, cerebral event. He believed that researchers studying perception should not construct artificially isolated and static experimental conditions that have nothing to do with everyday life — instead they should strive to approximate natural conditions. If they did so they would come to understand the senses not as passive mechanisms receiving valueless data, but as active, exploratory organs attuned to dynamic meanings already there in the environment.

These dynamic meanings, or “affordances” as Gibson has termed them, are the way that specific aspects of the natural environment directly address themselves to particular species or individuals. Thus, to a human a maple tree may afford “looking at” or “sitting under,” while to a sparrow it affords “perching,” and to a squirrel it affords “climbing.” But these values are not found inside the minds of the animals! Rather they are dynamic, addressive properties of the physical landscape itself, when the land is comprehended in a manner that does not artificially separate it from the life of the various organisms that inhabit it and contribute to its continuing evolution.

In short, for Gibson and those who carry on his work (the “direct perceptionists”), perception is elucidated as a reciprocal interchange between the living intentions of any animal and the dynamic affordances of its world. The psyche, as studied by these psychologists, is a property of the ecosystem as a whole.

MERLEAU-PONTY AND THE RECIPROCITY OF PERCEPTION

The French philosopher Maurice Merleau-Ponty had already come to some very analogous conclusions in his major study, The Phenomenology of Perception, published in France in 1945. [10]   He did not seek to build a finished theory of perception but simply to attend as closely as possible to the experience of perception, and to describe it afresh. In doing so he steadfastly refused to construct an explicit philosophical system that we might reify into yet another frozen concept, another “internal representation” to set between ourselves and our environment. Instead he sought a language, a new way of speaking that would not sever our living bond with the world around us.

One of the major accomplishments of his investigations was to show that the fluid creativity that we commonly associate with the human mind, or intellect, is in actuality an extension (and recapitulation) of a deep creativity already underway at the most immediate level of bodily experience. For Merleau-Ponty, it is the organic, sensitive body itself that perceives the world and, ultimately, thinks the world — not some interior and immaterial mind.

Through an intricate and lucid analysis, Merleau-Ponty slowly discloses perception as an almost magical activity in which what he calls the lived-body orients and responds to the active solicitations of the sensory world, a sort of conversation carried on, beneath all our speaking, between the body and the gesturing, sounding landscape it inhabits. In numerous later essays, Merleau-Ponty disclosed this perceptual nterchange between body and world as the very foundation of truth in history, in political thought and action, in art, and in science.

In the book on which he was working at the time of his sudden death in 1962 — published posthumously, in unfinished form, as The Visible and the Invisible [11]   — Merleau-Ponty took up his earlier analysis of perception and carried it a step further, seeking to describe experientially the actual world to which our senses give us access, the common domain that we investigate with our rationality and our science. He found that the “invisible” in humankind — the region of thought and ideality — is inextricably intertwined with the shifting, metamorphic, intelligent nature of the enveloping world. If perception gives way in us to thought and reflective awareness, then these are not properties closed within the human brain, but are the human body’s open reply to questions continually put to it by the subtle, self-organizing character of the natural environment.

Merleau-Ponty’s thought is far too complex and elusive to be summarized here. Yet it is possible to experience Merleau-Ponty’s radical solution to the traditional mind-body problem simply by dropping the conviction that one’s mind is anything other than the body itself. If one is successful in this then one may abruptly experience oneself in an entirely new manner — not as an immaterial intelligence inhabiting an alien, mechanical body, but as a magic, self-sensing form, a body that is itself awake and aware, from its toes to its fingers to its tongue to its ears: a thoughtful and self-reflective animate presence. (This corresponds, roughly, to the first stage in Merleau-Ponty’s investigation.)

Yet if one maintains this new awareness for a duration of time, becoming comfortable enough with it to move about without losing the awareness, one will begin to experience a corresponding shift in the physical environment. Birds, trees, even rivers and stones begin to stand forth as living, communicative presences.

For when my intelligence, or mind, does not think of itself as something separable from the living body, but starts to recognize its grounding in these senses and this material flesh, then it can no longer hold itself apart from the material world in which this body has its place. As soon as my awareness forfeits its claim to a total transcendence and acknowledges its dependence upon this physical form, then the whole of the physical world shudders and wakes. This experience corresponds to the second, unfinished phase in Merleau-Ponty’s writing, when he refers less often to the body as the locus of perceptual experience and begins to write of the collective Flesh, his term for the animate, sensitive existence that encompasses us (of which our own sentient bodies are but a part).

Thus Merleau-Ponty, who in his earlier work had disclosed the radically incarnate nature of awareness and intelligence, ends by elucidating the world itself from the point of view of the intelligent body — as a wild, self-creative, thoroughly animate macrocosmos. Perception is now understood as the continuous intertwining, or “chiasm” between one’s own flesh and the vast “Flesh of the World.”

So both Gibson and Merleau-Ponty, pursuing two different styles of analysis inherited from their respective intellectual traditions, arrived at an alternative understanding of perception – an understanding of perception not as a mostly internal, cerebral event, but as a direct and reciprocal interchange between the organism and its world. While Gibson’s followers strive to map this interchange in precise, systematic theorems, Merleau-Ponty sought a new language that could ground the various disciplines in an awareness of perception as radical participation. In doing so he began to uncover, hidden behind our abstractions, a sense of the Earth as a vast, inexhaustible entity, the forgotten ground of all our thoughts and sensations. [12]

These two steps toward a post-Cartesian epistemology are remarkably consonant with the Gaia hypothesis, and with the Gaian implication that perception itself is a communication, or communion, between an organism and the living biosphere.

THE ECOLOGY OF THE SENSES

Still, we must further clarify our Gaian definition of perception by answering two obvious objections. Some may object that it is meaningless to speak of perception as a direct communication between oneself and the planetary macrocosm, since in many situations one’s senses are directly engaged only in relation to another individual organism, as when one is simply talking with another person. Furthermore, even when one is perceptually attuned to many different phenomena at once — when, for example, one is hiking through a forest — still one’s senses are then interwoven within a single specific region of the planet, a bioregion or ecosystem that has its own internal coherence distinct from the planet as a whole. Therefore, if perception is a communion it is at best a communion with relative wholes within Gaia.

But this is merely a provisional objection. We may certainly define specific regions or worlds within Gaia as long as we acknowledge Gaia’s enigmatic presence behind these. Gaia reveals herself to us only locally, through particular places, particular ecologies. Yet if Lovelock’s hypothesis is correct, then it is the overall planetary metabolism that lends organic coherence to the myriad systems or wholes within it. A forest ecosystem is one such whole. A human culture is another, and when conversing among ourselves we are directly involved in the whole linguistic culture that provides the medium for our exchange. A closer look at perception is also called for at this point. Traditional research on perception has sought to study each sense as a separate and exclusive modality. Merleau-Ponty, however, has shown that to our immediate experience perception is a thoroughly synaesthetic phenomenon. In everyday life, in other words, the so-called separate senses are thoroughly blended and intertwined, and it is only in abstract reflection, or in the psychologist’s laboratory, that we are able to isolate the various senses from one another.

For example, when I perceive the waves that are breaking on the shore below my cabin, there is no separation of the sound of those waves from what I see of them. The swell of each wave as it rolls toward me, the tumbling crash of those waters before they sweep across the beach, only to hiss back down, overturning all the pebbles, to meet the next vortex — these are experiences in which visual, aural and tactile modalities all envelop and inform each other. A certain ocean smell, as well, permeates the whole exchange, lending it an unmistakable flavor.

Remarkably little is known about the mysterious chemical senses of smell and of taste. Within any textbook of perception it is difficult to find more than a few pages devoted to these senses, which seem to resist objective measurement and analysis. Yet it is with these subtle senses that we perceive the state of the very medium in which we move. We both smell and taste the atmosphere in the course of our breathing, and these sensations are so constant, so necessary, and yet so unconscious (or unattended to) that we may truly say they provide the hidden context for all the rest of our perceiving. And as Lovelock’s work indicates, the atmosphere is a complex but thoroughly integrated phenomenon, perhaps the most global of all the Earth’s attributes. As I become more aware that this organism I am not only perceives things through the atmosphere but also perceives the atmosphere itself — that I constantly smell, taste and touch the atmosphere as well as hear it rustling in the leaves and see it billowing the clouds — I will come to realize the extent to which my senses do indeed keep me in direct and intimate contact with the life of the biosphere as a whole.

A second important objection to our ecological view of ordinary perception — as a continuous communion with the animate Earth – will come from those who point out that there is much we perceive that is not of this planet: the other planets, the moon, the stars, and our own star, the sun. While obviously not unfounded, this objection still rests on the assumption that we dwell upon the surface of an essentially inert planet. Yet if we recognize Gaia as a self-regulating entity, we must recognize the enveloping atmosphere as a part of this entity. All that we know of other worlds reaches us via the rich and swirling atmosphere of our own world, filtered through the living lens of Earth’s sky. Even when we consider the dependence of our vision on the radiant light of the sun, we must acknowledge that the sunlight we know is entirely conditioned by the atmosphere that envelops, and is a part of, this living biosphere. While Gaia depends on the sun for its nourishment, we depend on Gaia. If we venture beyond the edges of its atmosphere, it is the living Earth that enables us to do so: we go in vehicles made of Earth and filled up with Earth’s sky — we need this in order to live.

This, I believe, is the deeper significance of James Lovelock’s ideas concerning what he calls the “terraforming” of other planets. By contemplating how humanity might someday transfer the complex Gaian metabolism to other planets in order to make them habitable by human life, Lovelock is underscoring the fact that neither humanity nor any other species we know can exist outside the incredibly complex Terran metabolism of which our own bodies and minds are an internal expression. If we wish to colonize other worlds, we shall have to bring this metabolism with us. We are entirely a part of the life that envelops this planet, and thus the living Earth as a whole is the constant intermediary between ourselves and the rest of the universe.

Our senses never outstrip the conditions of this living world, for they are the very embodiment of those conditions. Perception, we must realize, is more an attribute of the biosphere than the possession of any single species within it. The strange, echo-locating sensory systems of bats and of whales, the subtle heat sensors of snakes, the electroreception of certain fish and the magnetic field sensitivity of migratory birds are not random alternatives to our own range of senses; rather they are necessary adjuncts of our own sensitivity, born in response to variant aspects of a single interdependent whole.

Once perception is understood in this light — as interaction and exchange, as communion and deep communication — then several of the puzzles that haunt contemporary psychology will begin to resolve themselves. For instance, the notion of “extrasensory” perception” (itself a contradiction in term), may be recognized as a necessary by-product of the contemporary assumption that ordinary perception is an entirely mechanical phenomenon. If we assume that the senses are merely passive mechanisms geared to an environment of random events, then any experience of direct, nonverbal communication with other persons or other organisms will inevitably be construed as a bizarre event that takes place in some extraordinary dimension outside the material world.

But what if the living body, when healthy, is in constant communication with the space that surrounds it? What if the senses are not passive mechanisms but active, exploratory organs evolved in the depths of a living biosphere? We have only to consider the amount of chemical information regarding the shifting internal state of an organism that is continually exhaled, expelled, and secreted into the ambient air — information that may be picked up, intentionally or unintentionally, by the chemical senses of any nearby organism — to realize the extent to which a form of subtle communication may be carried on between our bodies at an entirely pre-reflective level.

In a like manner our eyes and our ears are capable of discriminations far more subtle than those to which we normally attend. When these organs are taken together with the organs of taste, smell and touch, as interactive components of a single synaesthetic perceptual system, we may discern that the living body is anatural clairvoyant, and that extrasensory perception is not extrasensory at all.

TOWARD A PSYCHOLOGICAL ECOLOGY

The recognition of a living Earth provides a condition for the resolution of numerous theoretical dilemmas. I have focused, in this article, on the paradox engendered by the assumption that, at least within the physical world, conscious awareness is an exclusively human attribute. If the external world exists only according to mechanical laws of determinacy and chance, what then is the point of contact between such a determinate world and human awareness? In others words, what is perception? I have suggested that in fact the external world is not devoid of awareness — that it is made up of numerous subjective experiences besides those of our single species — and furthermore that these myriad forms of biotic experience, human and nonhuman, may collectively constitute a coherent global experience, or life, that is not without its own creativity and sentience.

If such is the case, as the evidence for Gaia attests, then perception is no longer a paradox, for there is not the total disjunction between “inside” and “outside” worlds that was previously assumed. Just as the external world is subject to mathematical measurement and analysis, so also the internal world is subject to similar methods of study, as the burgeoning fields of neurobiology attest. But the reverse is also true. Just as the interior world of our psychological experience has many qualities that are ambiguous and indeterminate, so the external world now discloses its own indeterminacy and subjectivity — its own interiority, so to speak. Perception, then, is simply the communion and deep communication between our own organic intelligence and the creativity that surrounds us.

Recognition of the perceptual ramifications of the Gaia hypothesis is, I believe, essential to any genuine appraisal of the hypothesis. Without an awareness of Gaia as this very world that we engage not only with our scientific instruments but with our eyes, our ears, our noses and our skin — without the subjective discovery of Gaia as a sensory, perceptual and psychological power — we are apt to understand Lovelock’s discovery in exclusively biochemical terms, as yet another scientific abstraction, suitable for manipulating and engineering to fit our purposes.

Lovelock himself, in his speculations regarding the exportation of Gaia to the surface of Mars, [13]  seems oblivious to the psychological ramifications of Gaia. The idea that the living biosphere, once discovered, can be mechanically transferred to another planet, overlooks the extent to which the discovery of Gaia calls into question the instrumental relationship we currently maintain with our world. Recognizing Gaia from within, as a psychological presence, greatly constrains the extent to which we can consciously alter and manipulate the life of this planet for our own ends.

As I have attempted to show, the discovery of a unitary, self-regulating biosphere, if accepted, completely undermines the classical account of perception upon which each of the separate sciences, until now, has been based. If our senses, our perceptions, and our whole manner of thinking have taken shape in reciprocal coevolution and communion with a coherent living biosphere, then in all probability it is our own Earth whose traces we actually discover in our most abstract investigations of quantum and astronomical spaces, the living Earth peering back at us through all our equations. For until we have recognized perceptu ally our organic embeddedness in the collective life of the biosphere — until we have realigned our thoughts with our senses and our embodied situation — any perception of other worlds must remain hopelessly distorted.

The theoretical discourse of our time has largely alienated us from the world of our everyday senses, while accustoming us to speak casually of the most far-flung realities. Thus other galaxies, black holes, the birth of the universe, the origins of space and of time, all seem quite matter-of-fact phenomena easily encompassed by the marvelous human mind. But Gaia, as a reality that encompasses us, a phenomenon we are immediately in and of, suggests the inconsistency of such blackboard abstractions. Gaia is no mere formula — it is our own body, our flesh and our blood, the wind blowing past our ears and the hawks wheeling overhead. Understood thus with the senses, recognized from within, Gaia is far vaster, far more mysterious and eternal than anything we may ever hope to fathom.

I have suggested that the most radical element of the Gaia hypothesis, as presently formulated, may be the importance that it places on the air, the renewed awareness it brings us of the atmosphere itself as a palpable yet enigmatic phenomenon no less influential for its invisibility. In Native American cosmology, the air or the Wind is the most sacred of powers. It is the invisible principle that circulates both within us and around us, animating the thoughts of all breathing things as it moves the swaying trees and the clouds. [14]   And indeed, in countless human languages the words for spirit or psyche are derived from the same root as the words for wind and breath. Thus in English the word spirit is related to the word respiration through their common origin in the Latin word spiritus, meaning a breath, or a gust of wind. Likewise our word psyche, with all its recent derivations, has its roots in the ancient Greek psychein, which means to breathe or to blow (like the wind).

If we were to consult some hypothetical future human being about the real meaning of the word spirit, he or she might reply as follows: Spirit, as any post-industrial soul will tell you, is simply another word for the air, the wind, or the breath. The atmosphere is the spirit, the subtle awareness of this planet. We all dwell within the spirit of the Earth, and this spirit circulates within us. Our individual psyches, our separate subjectivities are all internal expressions of the invisible awareness, the air, the psyche of this world. And all our perceiving, the secret work of our eyes, our nostrils, our ears and our skin, is our constant communication and communion with the life of the whole. Just as, in breathing, we contribute to the ongoing life of the atmosphere, so also in seeing, in listening, in real touching and tasting we participate in the evolution of the living textures and colors that surround us, and thus lend our imaginations to the tasting and shaping of the Earth. Of course the spiders are doing this just as well…

[1] J. E. Lovelock, Gaia: A New Look at Life on Earth (New York: Oxford University Press, 1982), p. 9.

[2]  Brown and Margulis, ‘Contaminants and Desiccation Resistance: a Mechanism of Gaia,” in Mitchell B. Rambler, Lynn Margulis, and Rene Foster, Global Ecology: Towards a Science of the Biosphere (Boston: Academic Press, 1989).

[3]  lndeed it is likely that our forgetting of the air is at the root of the odd concept, so specific to our culture, of pure mind or mentality as an ideal sort of vacuum without physical attributes.

[4]  Lovelock & Margulis, “Gaia and Geognosy,” p. 2.

[5]  E. B. Titchener, An Outline of Psychology (New York: Macmillan, 1896).

[6]  Lovelock, Gaia. Also, Brown & Margulis, “Contaminants and Desiccation Resistance.”

[7]  Lovelock, Gaia, p. 9.

[8]  See, for example, Carl D. Hopkins, “Sensory Mechanisms in Animal Communication in Haliday & Slater, eds., Animal Behavior 2: communication (New York: Freeman and Co., 1983), as well as articles by Gerhardt and Wiley in the same text.

[9]  names J. Gibson, The Perception of the Visual World (Boston: Houghton Mifflin, 1950). The Senses Considered as Perceptual Systems (Boston: Houghton Mifflin, 1966). The Ecological Approach to Visual Perception, (Boston: Houghton Mifflin, 1979).

[10]  Maurice Merleau-Ponty, The Phenomenology of Perception, translated by Colin Smith (London: Routledge & Kegan Paul, 1962).

[11]  “Maurice Merleau-Ponty, The Visible and the Invisible, translated by Alphonso Lingis (Evanston, Illinois: Northwestern University Press, 1968).

[12]  For an in-depth discussion of Merleau-Ponty’s philosophy and its ecological implications, see Abram, “Merleau-Ponty and the Voice of the Earth,” in Environmental Ethics, Vol. 10, No. 2, Summer 1988.

[13]  J.E. Lovelock, The Greening of Mars (New York: St. Martins/Marek, 1984).

[14]  See, for instance, James K. McNeley, Holy Wind in Navaho Philosophy (Tucson: University of Arizona Press, 1981), on the Navaho concept of ‘Nilch’i.”

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The Gaia Hypothesis: Conjectures and Refutations

• Published: May 2003
• Volume 58 , pages 21–45, ( 2003 )

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• James W. Kirchner 1  

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The uncertainties surrounding global climate change provide ample evidence, if any were necessary, of the need for a whole-system view of the Earth. Arguably the most visible – and controversial – attempt to understand Earth as a system has been Lovelock's Gaia theory. Gaia has been a fruitful hypothesis generator, and has prompted many intriguing conjectures about how biological processes might contribute to planetary-scale regulation of atmospheric chemistry and climate. In many important cases, however, these conjectures are refuted by the available data. For example, Gaia theory predicts that the composition of the atmosphere should be tightly regulated by biological processes, but rates of carbon uptake into the biosphere have accelerated by only about 2% in response to the 35% rise in atmospheric CO 2 since pre-industrial times. Gaia theory would predict that atmospheric CO 2 should be more sensitively regulated by terrestrial ecosystem uptake (which is biologically mediated) than by ocean uptake (which is primarily abiotic), but both processes are about equally insensitive to atmospheric CO 2 levels. Gaia theory predicts that biological feedbacks should make the Earth system less sensitive to perturbation, but the best available data suggest that the net effect of biologically mediated feedbacks will be to amplify, not reduce, the Earth system's sensitivity to anthropogenic climate change. Gaia theory predicts that biological by-products in the atmosphere should act as planetary climate regulators, but the Vostok ice core indicates that CO 2 , CH 4 , and dimethyl sulfide – all biological by-products – function to make the Earth warmer when it is warm, and colder when it is cold. Gaia theory predicts that biological feedbacks should regulate Earth's climate over the long term, but peaks in paleotemperature correspond to peaks in paleo-CO 2 in records stretching back to the Permian; thus if CO 2 is biologically regulated as part of a global thermostat, that thermostat has been hooked up backwards for at least the past 300 million years. Gaia theory predicts that organisms alter their environment to their own benefit, but throughout most of the surface ocean (comprising more than half of the globe), nutrient depletion by plankton has almost created a biological desert, and is kept in check only by the nutrient starvation of the plankton themselves. Lastly, where organisms enhance their environment for themselves, they create positive feedback; thus Gaia theory's two central principles – first, that organisms stabilize their environment, and second, that organisms alter their environment in ways that benefit them – are mutually inconsistent with one another. These examples suggest that the further development of Gaia theory will require more deliberate comparison of theory and data.

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Kirchner, J.W. The Gaia Hypothesis: Conjectures and Refutations. Climatic Change 58 , 21–45 (2003). https://doi.org/10.1023/A:1023494111532

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DOI : https://doi.org/10.1023/A:1023494111532

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Gaia hypothesis

The Gaia (pronounced GAY-ah) hypothesis is the idea that Earth is a living organism and can regulate its own environment. This idea argues that Earth is able to maintain conditions that are favorable for life to survive on it, and that it is the living things on Earth that give the planet this ability.

Mother Earth

The idea that Earth and its atmosphere are some sort of "superorganism" was actually first proposed by Scottish geologist (a person specializing in the study of Earth) James Hutton (1726–1797), although this was not one of his more accepted and popular ideas. As a result, no one really pursued this notion until some 200 years later, when the English chemist James Lovelock (1919– ) put forth a similar idea in his 1979 book, Gaia: A New Look at Life on Earth. Gaia is the name of the Greek goddess of Earth and mother of the Titans. In modern times, the name has come to symbolize "Earth Mother" or "Living Earth." In this book, Lovelock proposed that Earth's biosphere (all the parts of Earth that make up the living world) acts as a single living system that if left alone, can regulate itself.

As to the name Gaia, the story goes that Lovelock was walking in the countryside surrounding his home in Wilshire, England, and met his neighbor, English novelist William Golding (1911–1993), author of Lord of the Flies and several other books. Telling Golding of his new theory, he then asked his advice about choosing a suitable name for it, and the result of this meeting was that the term "Gaia" was chosen because of its real connection to the Greek goddess who pulled the living world together out of chaos or complete disorder.

Origin of Earth's atmosphere

Lovelock arrived at this hypothesis by studying Earth's neighboring planets, Mars and Venus. Suggesting that chemistry and physics seemed to argue that these barren and hostile planets should have an atmosphere just like that of Earth, Lovelock stated that Earth's atmosphere is different because it has life on it. Both Mars and Venus have an atmosphere with about 95 percent carbon dioxide, while Earth's is about 79 percent nitrogen and 21 percent oxygen. He explained this dramatic difference by saying that Earth's atmosphere was probably very much like that of its neighbors at first, and that it was a world with hardly any life on it. The only form that did exist was what many consider to be the first forms of life—anaerobic (pronounced ANN-ay-roe-bik) bacteria that lived in the ocean. This type of bacteria cannot live in an oxygen environment, and its only job is to convert nitrates to nitrogen gas. This accounts for the beginnings of a nitrogen build-up in Earth's atmosphere.

Words to Know

Biosphere: The sum total of all lifeforms on Earth and the interaction among those lifeforms.

Feedback: Information that tells a system what the results of its actions are.

Homeostasis: State of being in balance; the tendency of an organism to maintain constant internal conditions despite large changes in the external environment.

Photosynthesis: Chemical process by which plants containing chlorophyll use sunlight to manufacture their own food by converting carbon dioxide and water to carbohydrates, releasing oxygen as a by-product.

Symbiosis: A pattern in which two or more organisms live in close connection with each other, often to the benefit of both or all organisms.

The oxygen essential to life as we know it did not start to accumulate in the atmosphere until organisms that were capable of photosynthesis evolved. Photosynthesis is the process that some algae and all plants use to convert chemically the Sun's light into food. This process uses carbon dioxide and water to make energy-packed glucose, and it gives off oxygen as a by-product. These very first photosynthesizers were a blue-green algae called cyanobacteria (pronounced SIGH-uh-no-bak-teer-eea) that live in water. Eventually, these organisms produced so much oxygen that they put the older anaerobic bacteria out of business. As a result, the only place that anaerobic bacteria could survive was on the deep-sea floor (as well as in heavily water-logged soil and in our own intestines). Love-lock's basic point was that the existence of life (bacteria) eventually made Earth a very different place by giving it an atmosphere.

Lovelock eventually went beyond the notion that life can change the environment and proposed the controversial Gaia hypothesis. He said that Gaia is the "Living Earth" and that Earth itself should be viewed as being alive. Like any living thing, it always strives to maintain constant or stable conditions for itself, called homeostasis (pronounced hoe-mee-o-STAY-sis). In the Gaia hypothesis, it is the presence and activities of life that keep Earth in homeostasis and allow it to regulate its systems and maintain steady-state conditions.

Cooperation over competition

Lovelock was supported in his hypothesis by American microbiologist Lynn Margulis (1918– ) who became his principal collaborator. Margulis not only provided support, but she brought her own scientific ability and achievements to the Gaia hypothesis. In her 1981 book, Symbiosis in Cell Evolution , Margulis had put forth the then-unheard of theory that life as we know it today evolved more from cooperation than from competition. She argued that the cellular ancestors of today's plants and animals were groups of primitive, formless bacteria cells called prokaryotes (pronounced pro-KAR-ee-oats). She stated that these simplest of bacteria formed symbiotic relationships—relationships that benefitted both organisms—which eventually led to the evolution of new lifeforms. Her theory is called endosymbiosis (pronounced en-doe-sim-bye-O-sis) and is based on the fact that bacteria routinely take and transfer bits of genetic material from each other.

Margulis then argued that simple bacteria eventually evolved into more complex eukaryotic (pronounced you-kar-ee-AH-tik) cells or cells with a nucleus. These types of cells form the basic structure of plants and animals. Her then-radical but now-accepted idea was that life evolved more out of cooperation (which is what symbiosis is all about) than it did out of competition (in which only the strong survive and reproduce). The simple prokaryotes did this by getting together and forming symbiotic groups or systems that increased their chances of survival. According to Margulis then, symbiosis, or the way different organisms adapt to living together to the benefit of each, was the major mechanism for change on Earth.

Most scientists now agree with her thesis that oxygen-using bacteria joined together with fermenting bacteria to form the basis of a type of new cell that eventually evolved into complex eukaryotes. For the Gaia hypothesis, the Margulis concept of symbiosis has proven to be a useful explanatory tool. Since it explains the origin and the evolution of life on Earth (by stating that symbiosis is the mechanism of change), it applies also to what continues to happen as the process of evolution goes on and on.

Gaia explained

The main idea behind the Gaia hypothesis can be both simple and complex. Often, several similar examples or analogies concerning the bodies of living organisms are used to make the Gaia concept easier to understand. One of these states that we could visualize Earth's rain forests as the lungs of the planet since they exchange oxygen and carbon dioxide. Earth's atmosphere could be thought of as its respiratory system, and its streams of moving water and larger rivers like its circulatory system, since they bring in clean water and flush out the system. Some say that the planet actually "breathes" because it contracts and expands with the Moon's gravitational pull, and the seasonal changes we all experience are said to reflect our own rhythmic bodily cycles.

Many of these analogies are useful in trying to explain the general idea behind the Gaia hypothesis, although they should not be taken literally. Lovelock, however, has stated that Earth is very much like the human body in that both can be viewed as a system of interacting components. He argues that just as our bodies are made up of billions of cells working together as a single living being, so too are the billions of different lifeforms on Earth working together (although unconsciously) to form a single, living "superorganism." Further, just as the processes or physiology of our bodies has its major systems (such as the nervous system, circulatory system, respiratory system, etc.), so, says Lovelock, Earth has its own "geophysiology." This geophysiology is made up of four main components: atmosphere (air), biosphere (all lifeforms), geosphere (soil and rock), and hydrosphere (water). Finally, just as our own physiological health depends on all of our systems being in good working condition and, above all, working together well, so, too, does Earth's geophysiology depend on its systems working in harmony.

Life is the regulating mechanism

Lovelock claims that all of the living things on Earth provide it with this necessary harmony. He states that these living things, altogether, control the physical and chemical conditions of the environment, and therefore it is life itself that provides the feedback that is so necessary to regulating something. Feedback mechanisms can detect and reverse any unwanted changes. A typical example of feedback is the thermostat in most homes. We set it to maintain a comfortable indoor temperature, usually somewhere in the range between 65°F (18°C) and 70°F (21°C). The thermostat is designed so that when the temperature falls below a certain setting, the furnace is turned on and begins to heat the house. When that temperature is reached and the thermostat senses it, the furnace is switched off. Our own bodies have several of these feedback mechanisms, all of which are geared to maintaining conditions within a certain proper and balanced range.

For Earth's critical balance, Lovelock says that it is the biosphere, or all of life on Earth, that functions as our thermostat or regulator. He says that the atmosphere, the oceans, the climate, and even the crust of Earth are regulated at a state that is comfortable for life because of the behavior of living organisms . This is the revolutionary lesson that the Gaia hypothesis wants to teach. It says that all of Earth's major components, such as the amount of oxygen and carbon dioxide in the atmosphere, the

saltiness of the oceans, and the temperature of our surface is regulated or kept in proper balance by the activities of the life it supports. He also states that this feedback system is self-regulating and that it happens automatically. As evidence that, if left alone, Earth can regulate itself, he asserts that it is the activity of living organisms that maintain the delicate balance between atmospheric carbon dioxide and oxygen. In a way, Love-lock argues that it is life itself that maintains the conditions favorable for the continuation of life. For example, he contends that it is no accident that the level of oxygen is kept remarkably constant in the atmosphere at 21 percent. Lovelock further offers several examples of cycles in the environment that work to keep things on an even keel.

Lovelock also warns that since Earth has the natural capacity to keep things in a stable range, human tampering with Earth's environmental balancing mechanisms places everyone at great risk. While environmentalists insist that human activity (such as industrial policies that result in harming Earth's ozone layer) is upsetting Earth's ability to regulate itself, others who feel differently argue that Earth can continue to survive very well no matter what humans do exactly because of its built-in adaptability.

Earth as seen from space

An important aspect about the Gaia hypothesis is that it offers scientists a new model to consider. Most agree that such a different type of model was probably not possible to consider seriously until humans went into space. However, once people could travel beyond the atmosphere of Earth and put enough distance between them and their planet, then they could view their home from an extra-terrestrial viewpoint. No doubt that the 1960s photographs of the blue, green, and white ball of life floating in the total darkness of outer space made both scientists and the public think of their home planet a little differently than they ever had before. These pictures of Earth must have brought to mind the notion that it resembled a single organism.

Although the Gaia hypothesis is still very controversial and has not been established scientifically (by being tested and proven quantitatively), it has already shown us the valuable notion of just how interdependent everything is on Earth. We now recognize that Earth's biological, physical, and chemical components or major parts regularly interact with and mutually affect one another, whether by accident or on purpose. Finally, it places great emphasis on what promises to be the planet's greatest future problem—the quality of Earth's environment and the role humans will play in Earth's destiny.

[ See also Biosphere ; Ecosystem ]

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ENVS203: Environmental Ethics, Justice, and World Views

The gaia hypothesis.

Read this page, which discusses the Gaia hypothesis. Do you believe that the theory holds weight, and that we could observe some of impacts as outlined in the hypothesis?

This teaching unit begins with a conceptual sketch of the Gaia Hypothesis, followed by a way of thinking about teaching found in John Dewey's philosophy of education that meets the challenge of Gaia in the classroom. There follows an outline of how Dewey unites scientific and moral problem solving for developing social policy which is, in turn, made applicable to solving problems in the environment. These ideas are translated into lesson plans, a course outline to integrate the unit into a course in ecology and biodiversity, and finally, analytical scoring rubrics.

1. The Gaia Hypothesis

Up until the last decade, few had thought of planet earth as in any sense alive. True in ancient Greece, Gaia was worshipped as the Goddess of the earth and pantheistic tribes had comparable deities of the earth that magically controlled their lives. An important step in this direction came from ecology where self-sustaining systems were discovered in which energy flowed and a delicate balance was maintained between all the organisms in the local environment. A meadow, a pond, or a forest were described as ecosystems. The abiotic factors were the inorganic or nonliving entities essential to the biotic factors or community of life that sustained each other – the producers, the consumers, and decomposers. Subseguently, James Lovelock in his Gaia Hypothesis suggests that the entire earth is one large ecosystem, homeostatically controlled. Furthermore, he shows that the environment was both created to meet life's needs as much as it has adapted to the conditions of the environment. Indeed life and the non-living are inseparable entities rather as the mind is to the body (1). It was more correct to say that the earth as a whole is self-sustaining, self-renewing, and self-creating. The earth is a living planet. Since life is sacred and encompasses both the biotic and the abiotic, the term Gaia seemed appropriate for the living earth.

We are used to the adage "think globally and act locally". Gaian thinking is really this idea in the fullest sense of its meaning. It is thinking through policies of management of the earth as a whole and to look at all other problems as subsets of this. It is a cybernetic approach to global village management where the problem is basically humans and culture, not nature. It is recognition that in our rape of mother earth, Gaia may dispose of us in the process of a planetary self-correcting homeostatic mechanism before we get to destroy Gaia.

As James Lovelock points out in 'Ages of Gaia', the central concept in the Gaia Hypothesis is homeostasis in which microbes, plants, soil organisms, and aquatic life play an integrated role. They control the flow of carbon, nitrogen, water, and other elements that go to make up life – with the sun turning the cycles at the homeostatically corrected temperature for life and by life. Life started taking control of the environment with the development of the double-helical nucleotides and these genes have driven the experiment of life with the environment as its encompassing cloak. (2)

The key example worked out by Lovelock was thermostatic control of the earth's surface temperature. He used the 'Daisy World' model as theoretical construct to demonstrate his theory. In simple outline, Gaia Hypothesis attributes the creation of earth's peculiar atmosphere to

(A) the stratospheric Carbon Dioxide blanket. When thick temperatures rise; when thin it cools. The ocean acts as a sink for Carbon Dioxide along with the rocks. Trees and cyanobacteria also absorb the gas and generate moisture. The Carbon Dioxide blanket above the stratosphere also keeps the oceans from evaporating away.

(B) For surface temperature to be around 13 degrees Celcius, the preferred average temperature for planetary life, it is necessary to have a correct mix of atmospheric gases. Air has the correct balance of 79% Nitrogen, 20% Oxygen and 0.003% Carbon Dioxide (all other planets have very high Carbon Dioxide and minimal Nitrogen and Oxygen). The Oxygen content comes from photosynthetic activity, the Nitrogen from decomposers (protists, fungi and bacteria). Oxygen forms ozone in the ionosphere and neutralizes ultraviolet radiation to protect life.

(C) The luminosity of the earth is lower and controlled by forest and vegetation (micro/macroflora) on land and in the oceans. When darker the temperature cools and when light the temperature rises (the Albedo factor). (3)

The gene flow of information that we call life, to an evolving experimentation problem-solving creation and adaptation to the environment, has an exponential history of development. It is Gaia's own self-development leading from the origin of the universe as bare energy leading up to higher levels of awareness. The levels of Gaia may be represented in powers of 10 from 4.5 billion years ago to the present generation born 45 years ago. The boxes are different by x10 to the power of 2 years. In the final box we have the highest level of self-awareness, a level that has the power to destroy Gaia – see the diagram opposite and the graph above it describing another exponential development, the human population explosion. We humans, though having evolved to an unprecedented level of self-awareness, have become a cancerous growth – a part of Gaia that is reproducing itself uncontrollably and fast killing its living host – Gaia.

It is the point of view of this teaching unit that Gaia protection is the fundamental starting point for all problem-solving in the environment. Norman Myers points out in "Atlas of Future Worlds", that protection of Gaia needs to be embedded in international law and all human behavior subjected to such a law (4). All other environmental and human problems pale by comparison. Accepting the axiom of the inviolability of Gaia would also help prioritize and suggest acceptable solutions to environmental problems, many of which are being sidetracked because of lack of agreement about what constitutes environmental moral culpability. The following unit then takes this as its a priori and seeks to involve students in the Gaia principle in any and every environmental problem that concerns them. Before developing the practicalities of such an undertaking, it seems necessary that we rethink our pedagogy to make sure that it is adequate to deal with the holistic mode of thinking required by the Gaia hypothesis, and rethinking John Dewey's educational philosophy is our place to begin.

2. Gaia and Education

John Dewey has had a profound influence on American education. The present reforms in science education are almost pure Deweyan. Those earlier reforms instituted in his name were not as successful as hoped but with research and creativity, the integrity of his ideas have been practically realized. However, the fundamentals of his philosophy of education have far-reaching implications that this unit seeks to include.

The first significant relevance is Dewey's own all-encompassing metaphor that he carried to all his ideas about education i.e. the metaphor of life itself. Life is self-renewing, self-adaptive, systemic, and social; hence education must have these characteristics to be effective.

"The most notable distinction between living things and inanimate things is that the former maintain themselves by renewal".(5) Education is such a process of renewal and transmission of resources that also includes ideas, skills, and so forth for the purpose of continuing life in the environment. Education communicates habits (skills) in doing, thinking, and feeling from generation to generation. The whole range of life's experience is passed on to individuals that enlarges their private experience. The individual 'goes out' of the self to find points of contact with that wider experience, the life of the species. (6)

Education manipulates meanings that have been called for by the need to interact and solve problems, those problems given by history, the present, and the challenge of the future. The ability to respond is natural to us – not an extrinsic capacity to be forced on the unwilling. It is not an act of conditioning but learning to see how ideas come together in a dynamic interplay to achieve some goal. The example Dewey gives to make his point is a baseball game. The game cannot be taught by memorizing rules or sequences of events. These may be used in the process of learning the game, but nothing is learned until the idea of the game is learned. Each of the parts have to come together so that it all makes sense. The test is whether the information works for the individual and they can be creatively used. When this is achieved the individual can demonstrate it and see how all the parts of the game are systemically interconnected to achieve the goal of winning and so forth. In this unit, problems will be thought through in such a 'feedback' loop.

At the heart of education is the idea of growth and this is equally characteristic of life as it moves from inception to death. Dewey's key ideas in this respect are 'reorganizing, reconstructing and transformation'.

Education by contrast is not static and not extrinsic. It is about taking the past into the future with thought, inventiveness and initiative.(7) Gaia problem solving challenges us all to break out of the static 'business as usual' ways of thinking.

The relevance to Gaian thought is that education must be taken out of its abstract and past orientation so as to apply past knowledge to the present and future. We need to move out of the Newtonian universe and move into the contemporary world of nonlinear physics, holistic math, creative chaos, and global cultural dialogue. Education must transcend meeting the interests of the status quo, class (business) privilege, or nationalist self-interest, for the purposes of all life, all of humanity, and for responding creatively to the environment. (8)

As Gaia is sacred and has its own ends and meanings, so also education provides its own interests, its own intrinsic ends. What is intrinsic, however, is open-ended, flexible, responsive, a shared activity, personal, and problem-solving. It is intelligent and springs from the student's own natural intelligence. It is its own discipline.

Dewey does not equate education with mere biological life but with reflective thought within the biological process of living in the environment. The essence of education is thinking within experience. Intelligence is not limited to humans. Humans are more adapted to finding a reflective solution to an environmental problem. Reflective experience or intelligent thought may be summarized as follows and is clearly a generalized scientific way of thinking that can be applied to any kind of experience of any kind.

perplexity, doubt, confusion in a situation (a problem/question) a tentative interpretation (hypothesis, projected answer) a careful detailed survey or examination of the experience (observations to clarify the problem) hypothesis (rational explanation) stated with independent variables (causes) and dependent variables (effects) test the explanation by effecting a cause to produce an effect or in other words, live the thought within an experience to see if it gives integrity or coherence to the event. (9)

Methodology in teaching is then no more nor less than the method of intelligent thinking. Students cannot learn this unless they participate in an event that requires active reflection. It cannot be isolated from the world but part and parcel of an action that becomes part of a growing world of experience. Books bring that accumulation of global experience to the student but it has to become a direct experience to become meaningful. The task of the teacher is to help mediate 'universal' and private experience.

In Dewey's major opus 'Democracy and Education', he elaborates the above in terms of the various disciplines – geography, history, humanities, science, and so forth (10). He also apples it to the social spirit, the essence of morality. In the following teaching unit, we will focus more of the implication of his educational theory to ethics and problem solving, particularly as they relate to environmental crises of Gaian proportions. The relevance of Dewey's pedagogy above will be highlighted too.

3. Developing a Social Policy

From the reasoning above, a teaching methodology will develop out of the steps needed to think intelligently when confronted by some aspect of the environment that we experience or live in. It is essentially scientific but since we are developing social policy we are also operating at a moral level of reasoning. Can such a methodology work for moral reasoning? In my teaching unit on genetics (YNHTI 1996), I set out Dewey's arguments for the appropriateness of scientific reasoning when making ethical judgments. His key justifications are as follows:

Moral judgments, as science, deals with time and space since both concern antecedents and consequences. In both science and morality, universals are abstracted out of particular events and actual contexts. Both concern universal 'laws' that only mean anything as predicators in actual situations. Science and morality both concern judgments on experiences that require reflection and then action to test theoretical understandings. These are tested as events involving some action, the results of which are used to confirm or deny the validity of the prior reflections and judgments. Science demands that reason be subjected to the hard knocks of experience. Similarly morality must justify itself in terms of actual experienced problems. Neither can hide behind appeals to transcendence independent of experience if they are to claim to be true. Both science and morality involve feeling awareness, rational cognition and action to test validity of the relationship between feeling and thought. Feeling awareness in both science and morality is attention to some aspect of the immediacy of experience that calls forth sentient interest, goals and vision of possibilities (in morality, love is an example of this). Cognition consists of logical connections in experience based on cause and effect. Objective thought in morality and science comes from acting out this reasoning within the environment (in morality, moral principles are reasoning within an experience such as love). If the consequences of action meet those expected by reason and those desired by the original feeling awareness (that drew one's attention to this aspect of the environment in the first place) then both science and morality have reasonable grounds for objectivity. Since methodology of making scientific and moral judgments are analogous, then the use of the following scientific or intelligent method of making social policies to solve problems in the environment are legitimated.

To simplify the above, we may use the life-skills problem-solving schema described below that all teachers in New Haven Public Schools are expected to use, where applicable, across all academic disciplines. What follows is a practical application of this applied to the population crisis.

(i) Defining the Problem

a. Population is the root cause of pollution and since population increases exponentially so pollution is increasing exponentially and so necessarily uncontrollably.

b. Pollution of air, water, and soil means loss of available resources for the expanding population.

c. Population drives consumption that depletes resources and prevents a balanced or sustainable economy with the environment. It drives the need for synthetics and the need for garbage disposal that further pollutes and cuts back on available land and resources.

d. Population increase drives the need to use mass farming techniques such as mono-genetic crops and pesticides that only increases productivity of crop production in the short term. It increases the risk of loss of protection from pests in the future and toxicity to life in general. In the process, further environmental damage threatens the existing level of human population.

e. Population increase means reduction of forests to provide fuel and more cultivated land, more houses and recreational space, etc. Loss of forests threatens global homeostatic control of global temperature.

If the temperature goes up there is flooding and increased rate of desertification, if the temperature goes down, there is a movement towards a glacial age. In either case, there is more land lost to farming.

f. Increase in population means increased dependence upon oil and other imported goods that decreases national security and so increases military expenditure that reduces resources available for feeding the population etc

g. Increase in population ultimately threatens all environmental treaties because the struggle for survival will justify governments to abandon them, that then in turn may lead to qualitative leaps in environmental destruction, and as such possibly lead to death of Gaia or devastating loss of human life to levels below existing population.

(ii) Hypothetical Solutions

a) Give tax and social benefits as incentives to 2 children families and penalties for exceeding this number.

b) Require all synthetics to be either biodegradable or able to be recycled on a sustainable basis.

c) Agribusiness must justify all management and farming policies based upon long term sustainable policies, organic solutions to pest and preservation of genetic diversity in the environment.

d) Enforcement of 'greenbelts' around all forest and woodlands. Cutting of trees must not threaten a complex ecosystem in which they live.

e) Reduce dependence upon foreign imports to reduce military expenditure. Reduce foreign debt by limiting profits that can be made on loans.

f) Support an international economic order that requires foreign trade to be based upon the best use of natural resources consistent with local climate or distinctive biome needs.

g) Give priority to all plans that address issues solving systemic problems.

(iii) Determine what criteria would be used to deem plans/solutions as good/bad or better/worse. (controlling variables).

The task is now to anticipate consequences of the hypothetical solutions that have been imagined. In this case, we are interested in:

• outcomes for the government, state or wider community material or nonmaterial.
• outcomes for those immediately involved.
• outcomes for extended family and others directly affected.
• anticipated outcomes based upon research into comparable situations, for example China.
• anticipate costs to different sectors of the economy and ways to deal with this.

(iv) Procedure/Materials/Presentation of Data.

Choose the best hypothetical plan and fully write out how it would be implemented with list of resources and costs incurred. Plan data tables, graphs, and so forth to determine how outcomes can be measured and presented.

(v) Conclusion

Recommend implementing the plan that appears to offer the best outcomes. Point out limitations and expected arrears for refinement.

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The Gaia Hypothesis: Is the Earth Alive?

More than one astronaut looking back at our planet has been awed into concluding that this blue and green globe is, in fact, a living being. Of course, many native peoples the world over have always believed (and functioned on the premise) that the earth is alive.

And now contemporary scientists are talking more and more about the Gaia hypothesis: the proposition that, in some ways, the planet does behave like a living system. (Gaia pronounced “Guy-uh” — was the Greek goddess of the earth.)

“What’s that?” you say. “Scientists are saying the earth is alive?” Well, the honest answer to that is “No, but  . . .” And the “but” becomes quite fascinating.

British scientist James Lovelock, the person most responsible for the Gaia hypothesis, was working for NASA when he first reached his living system insight questioning is the earth alive? Surprisingly, though, at the time he was creating tests to detect life on Mars!

Lovelock had taken the approach that, rather than have satellites take minute soil tests on the red planet (using what he described as “glorified flea detectors”), scientists should look at Mars’ atmosphere to see if it has any concentrations of gases that could exist only if they were maintained by living organisms. To test that idea, Lovelock looked at the atmosphere of our own planet. Sure enough, earth’s air contains large quantities of highly reactive gases — such as oxygen and methane — that naturally break down into other compounds. “If chemical thermodynamics alone mattered,” he wrote, “almost all the oxygen and most of the nitrogen in the atmosphere ought to have ended up in the sea combined as nitrate ion.”

This simple discovery later developed into one of Lovelock’s original arguments for Gaia: Something is maintaining numerous reactive gases in our atmosphere in an equilibrium steady state. (Mars, by the way, flunked the “active atmosphere” test.)

The second, and even more compelling, argument was that over the millenia the earth has somehow regulated its own temperature. When life began on our planet four billion years ago, the sun was 30% cooler than it is today. Yet, from then until now, the temperature of the earth’s surface has remained within the critical life-supporting range of 15 degrees to 30 degrees Celsiu. The level of CO, has dropped a hundred fold in those four billion years, reducing the “greenhouse” heat-holding effect of the atmosphere even while the sun was radiating more heat. The result? The earth has kept itself at a constant temperature . . . just as our own bodies do!

Temperature and a reactive atmosphere are just two of the factors kept in balance by the earth. One must also notice that if — as Lovelock states — “humidity or salinity or acidity or any one of a number of other variables had strayed outside a narrow range of values for any length of time, life would have been annihilated.”

The interactive mechanisms that accomplish this self — regulation are too complex for current science to quantify, so Lovelock often uses a simplified model of an imaginary “Daisy World” to suggest how the system might work. Suppose there was a planet that supported only two plant species, white daisies and black daisies. Since the white ones reflect more heat than black ones, they would fare better when the planet was unusually hot. The reverse would also be true: Black daisies, being better heat absorbers, could survive better during cool periods.

But what would happen if Daisy World was cool for an extended time? Black daisies would take over more and more of the land surface, increasing the absorption capacity of the planet and thereby warming it up. In time, the temperature would rise to the best range for white daisies. Those would spread, and the black ones would largely die back. But that event would increase the heat reflectiveness of the planet, thus eventually cooling its surface.

By such means, the black and white daisies would balance each other and keep the planet’s temperature from ever getting too hot or too cold to support plant life. On a much more complex level, the organisms on our own planet must work together to stabilize the earth.

In sum (again quoting Lovelock), “The Gaia hypothesis sees the earth as a self-regulating system able to maintain the climate, the atmosphere, the soil, and the ocean composition at a fixed state that’s favorable for life. It’s often taken that the capacity for self regulation in the face of perturbation, change, disasters, and so on is a very strong characteristic of living things and, in that sense, the earth is a living thing.”

But Really, is the Earth Alive?

Lovelock is saying that the evolution of life and the evolution of the planet have not been separate phenomena but one single, tightly coupled process. Life does not simply adapt to its environment but, through various feedback loops, coevolves with it. This unifying, whole systems view is beginning to gain ground with scientists. And the fascinating search for Gaia’s mechanisms is already leading to new areas of exploration. Biologist Lynn Margulis, who worked closely with Lovelock on the original hypothesis, now studies the roles that hardy microorganisms may play in regulating the atmosphere. She’s found 200 or so mostly dormant microorganisms in tiny culture samples, each ready under the right conditions — to perform its function and give off its particular gaseous emission, depending on surrounding conditions. Atmospheric scientist Pat Zimmerman examined the intestinal bacteria of termites as a source of atmospheric methane and learned that since there are about 1,500 pounds of termites per human being on earth, and since the wood nibblers go through the equivalent of one-third of the new plant carbon created every year, they may produce half of the methane in the atmosphere!

But Lovelock’s words have at times suggested that the planet’s totality of life is deliberately working to better its condition and increase itself. Adding such an aspect of purposefulness (even consciousness) to Gaia grates on most otherwise sympathetic scientists. Any hints that the whole system may indeed be alive are taboo to them — that’s talking religion. And as Stanford Research Institute senior policy analyst Don Michael puts it, “Science and spirit are different realms. They are not in conflict, but there’s no interface between the two.” Lovelock himself now seems to back away from such implications: “There’s no foresight or planning involved on the part of life in regulating the planet. It’s just a kind of automatic process.”

That hasn’t stopped many non-scientists from drawing their own conclusions about the implications of the Gaia hypothesis. Like several other environmentalists, Nancy Todd, co-founder of the New Alchemy Institute, sees Gaia as a means of helping humans be better planetary stewards. “Gaia,” she states, “is the only metaphor scientific and mythologic enough to see us through our present crisis and lead to a resacralization of the world.”

Indigenous peoples who have always felt themselves in communication with a living planet feel that interest in Gaia is a sign that technological cultures are beginning to agree with them. Prem Das, a shaman — healer in Tepic, Mexico, tells outsiders that of course the planet is alive: “The Earth is speaking all the time. But it doesn’t speak English. It speaks Earthese. We just need to learn how to listen.”

Psychologist Jim Swan-producer of a national symposium called “Is the Earth a Living Organism?” — feels the Gaia hypothesis may herald a paradigmatic shift that would affect almost all areas of thought and be greatly beneficial to society. He says, “You can’t prove earth is alive scientifically, because living is a property beyond the very limited structure of current science. But you can know it for yourself through direct experience — through vision quests in sacred places, for example. And such knowledge has incredible practical utility. Science based on it would help bind us to each other, not blow each other up. Experience of the living earth can also have great benefits for mental and physical health — especially in our society, which rejects feeling, intuitive modes of being. The experience can also change your life priorities. Almost all our country’s great environmentalists — including Burroughs, Thoreau, Carson, and Muir — have felt a oneness with the planet and had that as a motivation for their actions.”

Earthly Thoughts in the Meantime

While Gaian scientists stay clear of such thoughts, the hypothesis is beginning to motivate their actions, as well. Dr. Stephen Schneider of the National Center for Atmospheric Research points out that although Gaia’s regulatory mechanisms may help assure the long-term existence of life on the planet, they may not assure the short-term survival of our own individual species — a species that may be making the planet too hot for its own good. “And I’m a chauvinist for human beings,” he confesses.

Even Lovelock, for all his British aplomb, agrees: “The clearing of the tropical forests and the addition of carbon dioxide to the atmosphere by fossil fuel burning act both in the same way to stress a system which is already near the limit of its capacity to regulate. And the effect of this perturbation might cause us to jump to a new stable state in the very near future. I imagine if the system does flip to a different stable state, there will be a sudden and enormous change in speciation, just as there was when the dinosaurs vanished. There will be a new biota that will be fit for the new environment. But I doubt it will be very comfortable for us.”

So, if widely understood, the Gaia hypothesis could help us avoid such a catastrophe. Whether the idea is adopted as a new spiritual credo or an automatic mechanism, it may be a notion whose time has come . . . not a moment too soon.

EDITOR’S NOTE: Lovelock’s book Gaia: A New Look at Life on Earth is available for $6.95 postpaid from Oxford University Press, NJ.

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Journal of Materials Chemistry A

2d conductive metal–organic frameworks for no electrochemical reduction: a first-principles study †.

* Corresponding authors

a Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China E-mail: [email protected]

b School of Material Science and Chemical Engineering, Institute of Mass Spectrometry, Ningbo University, Fenghua Road 818, Ningbo 315211, China E-mail: [email protected]

c Key Laboratory of Precision and Intelligent Chemistry, Department of Chemical Physics, Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China E-mail: [email protected]

Designing flexible single-atom catalysts with tunable single-atom centers and coordination environments is crucial for highly active and selective electrochemical catalysis. Using density functional theory calculations, a range of 32 two-dimensional conductive metal–organic frameworks (cMOFs: TMX 4 –HTPs, TM = Sc–Ni, X = N, O, P, S) were investigated as efficient catalysts for electrocatalytic nitric oxide reduction reaction (eNORR) towards ammonia. By screening for stability, selectivity, and activity, eight TMX 4 –HTPs are identified as potential high-performance catalysts. Among them, MnO 4 –HTP delivers the lowest overpotential of only 0.21 V. Using this system as an example, the solvent effect, protonation ability of the potential-limiting step, and constant potential model were additionally considered and simulated. The computed results further verify the predicted potential of these catalysts as eNORR catalysts. Furthermore, descriptors are obtained to evaluate the competitive ability of key adsorbates using the sure independence screening and sparsifying operator method. All parameters are related to the intrinsic properties of TM (such as electronegativity, valence electron number, first ionization energy, and relative atomic mass) without extensive calculations. This work paves the way for highly active and selective cMOF-based electrocatalysts for eNORR.

• This article is part of the themed collection: Journal of Materials Chemistry A HOT Papers

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2D conductive metal–organic frameworks for NO electrochemical reduction: a first-principles study

X. Chen, X. Zhu, Z. Xia, S. Qian, Y. Zhou, Q. Luo and J. Yang, J. Mater. Chem. A , 2024, Advance Article , DOI: 10.1039/D4TA04795H

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Trump and Allies Forge Plans to Increase Presidential Power in 2025

The former president and his backers aim to strengthen the power of the White House and limit the independence of federal agencies.

Donald J. Trump intends to bring independent regulatory agencies under direct presidential control. Credit... Doug Mills/The New York Times

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By Jonathan Swan Charlie Savage and Maggie Haberman

• Published July 17, 2023 Updated July 18, 2023

Donald J. Trump and his allies are planning a sweeping expansion of presidential power over the machinery of government if voters return him to the White House in 2025, reshaping the structure of the executive branch to concentrate far greater authority directly in his hands.

Their plans to centralize more power in the Oval Office stretch far beyond the former president’s recent remarks that he would order a criminal investigation into his political rival, President Biden, signaling his intent to end the post-Watergate norm of Justice Department independence from White House political control.

Mr. Trump and his associates have a broader goal: to alter the balance of power by increasing the president’s authority over every part of the federal government that now operates, by either law or tradition, with any measure of independence from political interference by the White House, according to a review of his campaign policy proposals and interviews with people close to him.

Mr. Trump intends to bring independent agencies — like the Federal Communications Commission, which makes and enforces rules for television and internet companies, and the Federal Trade Commission, which enforces various antitrust and other consumer protection rules against businesses — under direct presidential control.

He wants to revive the practice of “impounding” funds, refusing to spend money Congress has appropriated for programs a president doesn’t like — a tactic that lawmakers banned under President Richard Nixon.

He intends to strip employment protections from tens of thousands of career civil servants, making it easier to replace them if they are deemed obstacles to his agenda. And he plans to scour the intelligence agencies, the State Department and the defense bureaucracies to remove officials he has vilified as “the sick political class that hates our country.”

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