Boris Shoshitaishvili is a science studies scholar with a background in evolutionary biology, comparative literature and ancient Greek epic poetry. He is a 2022-23 Berggruen Institute fellow.
Two and a half millennia ago, the philosopher Empedocles imagined a cosmos that alternated between the dominance of love and strife. Whenever love was at its zenith, the universe as a whole assumed the shape of a sphere, the perfect form of embrace and centered connection.
After Empedocles, cosmic spheres became crucial for representing the universe as a harmonious, sheltering home across a long tradition of astronomical models. In this geocentric tradition, our planet sits at the heart of a series of adjacent spheres. Each sphere beyond Earth contains a different planet, and the movement of the spheres produces a cosmic music, a musica universalis.
This “image of the cosmos,” as C.S. Lewis called it, is mostly lost today, but something of its order, beauty and comfort lives on in our understanding of the planet we inhabit. According to the terminology of modern geochemistry, Earth is made up of “spheres”: the lithosphere, the hydrosphere and atmosphere are nearly concentric, have complex cycles of their own and interact with each other, often in harmonious ways.
The language of spheres and harmony is a powerful and poetic way to imagine the planet. It led to the understanding of life as a “biosphere,” and more recently of our own species forming a new sphere over the biosphere, an envelope of intelligence and technology called the “noosphere,” the sphere of noos — a Greek word meaning “mind” or “reason.”
This vision of humankind as an expansive and potentially mindful world-embracing layer provides more than a spatial description of how humans have spread around much of the Earth’s surface. It also offers a poetic background for a specific kind of “planetary identity,” a way of seeing ourselves as participants in the planet’s harmonies, one sphere among the others.
But the noosphere is not the only image of planetary identity offered by the Earth sciences. Two other visions of planetary humankind have become broadly influential in the last 50 years. The “Anthropocene” has been officially proposed as the new geological epoch we inhabit, a time when human activity is pushing the Earth toward potentially catastrophic planetary disruption. Humankind in the Anthropocene is not a sphere but a geological force destabilizing an ancient system.
And “Gaia theory” offers a third planetary vision, one in which human beings are ambivalent members of an immense living body, a self-regulating planet-sized superorganism called Gaia, after the ancient Greek goddess of the Earth.
The power of these paradigms is that each is at least as evocative symbolically as it is provocative scientifically. Each positions human beings in a specific planetary context underpinned by an ancient metaphor and its poetry: the cosmic sphere, the world force, the collective body. Their poetics may be the first hints of the planet’s growing symbolic presence in human life.
The Noosphere
In the early 1920s, alongside the ravages of a worldwide influenza pandemic, Europeans faced the mass ruin of what H.G. Wells had idealistically called “the war to end war.” It was as incongruent a time for extreme optimism about the future of human society and technology as any, and yet three thinkers meeting in Paris took heart in each other’s hopes for a planetary humankind. The trio speculated that human beings were binding together into harmonious unity across the globe through reason, cultural connection, trade and technology.
The geochemist Vladimir Vernadsky had just arrived in the French capital from the newly forming Soviet Union to give lectures on his expansive theory of the biosphere. In attendance were the philosopher-mathematician Édouard Le Roy and the paleontologist-priest Pierre Teilhard de Chardin. Vernadsky presented a vision of the biosphere as a vibrant, ancient and planet-wide zone of life woven through other spheres of planetary scope. Though relatively small in mass, the biosphere had the ability to translate the sun’s energy into living activity that collectively transformed the face of the Earth. Inspired by life’s planetary extent and influence, the three turned their attention to the significance of humanity’s presence in that realm.
That focus led them to propose a new entry in the established geochemical terminology, a reinterpretation of the total sum of human activity and artifacts as the formation of a planetary sphere of mind: a noosphere. They saw this planetary layer — billions of years younger than the biosphere and comprising its own vast diversities of ideas, thoughts, affects and technologies — emerging and interacting with the older Earth spheres.
In their eyes, the noosphere formed through human cultures and technological knowledge connecting in the processes of globalization, similar to the way the biosphere emerged out of ecosystemic relationships among diverging species, physiologies and metabolisms. Over the following decades, Vernadsky and Teilhard introduced separate conceptualizations of the noosphere, their major publications on it appearing in the midst and aftermath of a second, even more deadly world war.
Vernadsky often invoked the thematic links between cosmic spheres, music and harmony. For the epigraph of his book on the biosphere, he chose verses from the poet Fyodor Tyutchev that privileged harmony: “There is an untroubled harmony in everything, a full consonance in nature; only in our illusory freedom do we feel at variance with it.” And in his final publication on the noosphere, Vernadsky concluded with the harmony-themed conviction that human democratic ideals were “in tune with the elemental geological processes, with the laws of nature, and with the noosphere.” Such musical associations to this day animate our ideals of living “in harmony” with the natural world, exemplified in the ongoing resolutions of the U.N. Harmony with Nature Program.
However, contemporary thinkers inclined to think in spherical terms have introduced two less celebratory conceptions of human-associated planetary spheres: the “technosphere” and the “infosphere.”
There is concern that the human technosphere is now an unbearable burden upon the biosphere: The best scientific estimates suggest that the total mass of human constructions on the planet now equals or even outweighs all biomass. Others worry that our algorithmically and digitally mediated cognitive and social environments have coalesced into the oppressive form of an infosphere “rising above thought like a Leviathan.” Moreover, the rise of a powerful infosphere means not just human communities dominating nature but also splintering into echo chambers and digital silos, potentially even geopolitically “parallel and often competing ‘hemispherical stacks’ of computational infrastructure.”
What would harmony mean for the technosphere and infosphere? They have nearly opposite natures. The technosphere is made up of the materials, infrastructure and machinery of our technologies, along with the vast amount of energy all of that uses. Meanwhile, the infosphere suggests a zone of knowledge-production, communication, data storage and meaning-making (“cyberspace” being one “region” of the infosphere) that is less materially substantial but still dependent on the technosphere. It is almost as though a new ethereal atmosphere (the infosphere) was differentiating itself from a new weighty lithosphere (the technosphere).
The disharmony of the technosphere lies in how technologies and infrastructure disrupt the biosphere through energy needs and by displacing living organisms. The development of the infosphere could mitigate these effects to some extent: Human beings today can more deftly engage one another across time and space through digital communication. But while infospheric developments can lead to reductions in technospheric demands, they can also distort communication and knowledge-making, creating cacophonies and disharmonies, coarsening civic discourse, enabling conspiracy thinking or even “downgrading humans.”
A fuller vision of planetary spheres could help structure how we think about the interrelated challenges of the 21st century. The utopian noosphere of Vernadsky and Teilhard could be reformulated into a more specific aspirational vision in which the noosphere figures as the potential expression of the biosphere, technosphere and infosphere in greater harmony. This overarching goal could serve as an ideal not far from planetary scientists’ recent theory of a “working mature technosphere, which can then develop self-maintaining planetary intelligence.”
The Anthropocene
When the scientists Paul Crutzen and Eugene Stoermer first presented their idea of “the Anthropocene” 20 years ago, they defined it through a powerful metaphor: a new epoch where humankind acted, for the first time, as a “major geological force.” Similar descriptions of humanity as a planetary or geophysical force have been prominent in Anthropocene science and commentary ever since. The centrality of the concept of force in the Anthropocene meshes with widespread alarm about global human impacts and anthropogenic pressures on the Earth system.
This network of physics metaphors (force, impact, pressure) scaled to the planetary carries us into another experience of the human-Earth relationship, one that’s different from the harmony-promising vision of the spheres. The Anthropocene presents the Earth as a dynamic system of countless forces, from the geophysical and chemical to the biological, whose deep-time stability is being swiftly undone by a new mega-force gathering out of human societies and technologies. Less a toiling Sisyphus, humankind in the Anthropocene is a mindless titanic Atlas, propelling an ancient world into unprecedented states.
The metaphor of humanity as a force has implications beyond directing our attention to the dangers of crossing climate “tipping points” and “planetary boundaries.” There is a strong call to action implicit in conceptualizing humankind as forcefully pressing against the ancient matrix we call the Earth system. This call to action helps make the Anthropocene not only a scientific geochronological designation (like prior epochs, such as the Holocene) but an orientation toward human planetary presence, a “paradigm dressed as epoch,” as political theorist Jeremy Baskin has called it.
The asymmetry of timescales and stability between human and planet inherent in the Anthropocene vision adds urgency to efforts to reorganize human techno-social force(s) into a more planetarily stable matrix — i.e. to achieve global arrangements of human forces that respect planetary boundaries.
Much of the debate lies in how to turn the sense of alarm inspired by seeing ourselves as an out-of-control geological force into broad changes that reintegrate humankind into the Earth system. A “good” or “mature Anthropocene” may be possible, but who will bear the costs and risks of the mindful interventions and collective self-regulations necessary to achieve a dynamic balance of more-than-living, more-than-human and human forces on a planetary scale?
Consider, for example, a geoengineering scheme, such as the idea of releasing sulfates into the atmosphere to reduce incoming solar radiation and cool the Earth’s surface. Such plans assume human beings can mindfully apply technology at the planetary level to counter the unintended planetary force created by the sum of all human lower-scale applications of technologies. Is this kind of intervention beyond human institutions and knowledge? And who will participate in the decision-making process? How will the diverse interests of multispecies life be represented?
Expanding identity to a new scale, especially the planetary, carries the risk of unjustly subsuming differences in responsibility and cost under a blanket of universality. It can cause the whole to appear more monolithic, inclusive or egalitarian than it really is. Yet one of the prospects of fostering a thoughtful poetics of planetary identity is precisely that it can draw attention to inherent tensions in the collective-constituency relationship, since different metaphors and narratives give these tensions different shapes and expressions.
In the case of the Anthropocene, there is a ready step from the metaphor of cumulative anthropogenic force to concerns about differential human power, as scholars like Dipesh Chakrabarty have noted. The two conceptual systems of force and power can cue each other. The poetics of human planetary force, in other words, may at best enhance rather than deflect our attention to the inequalities and abuses of intra-human privileges, responsibilities and burdens.
Gaia
According to James Lovelock and Lynn Margulis’s Gaia theory, the Earth, together with the living beings entangled in its processes, is alive. Their proposal was based on a key biological quality they considered the biosphere and Earth as a whole to possess: homeostasis, a living organism’s ability to modulate a complex internal environment in response to change and thus maintain the conditions of its own existence.
Living beings possess a suite of homeostatic mechanisms to keep body temperature, pH levels, fluid balance, concentrations of elements and ions and many other aspects of physiology in favorable ranges. Lovelock and Margulis began thinking “geo-physiologically” that the total of biospheric and geochemical processes create planet-wide homeostasis. Lovelock buttressed this vision with ideas and language drawn from his cybernetics background (“feedback loops” and “control systems”) and Margulis situated Gaia into her wide-ranging explorations of biological symbiosis.
For the planet, Lovelock and Margulis proposed that mechanisms of global homeostasis driven by the biosphere could help resolve what is now called the “faint young sun problem.” The sun’s luminosity has increased 30% over the 4.5 billion years of Earth’s history, yet the Earth’s temperature does not appear to have increased significantly in proportion. When the sun was younger and fainter, the early Earth was still fairly warm; now that the sun shines hotter, the Earth hasn’t heated to a comparable extent.
According to Lovelock and Margulis, the biosphere has helped maintain Earth’s surface temperature in a range supportive of complex life (and liquid water) by regulating the mixture of gases in the atmosphere, increasing or decreasing the overall greenhouse effect in response to the changing strength of heat from the sun. The carbon dioxide-rich atmosphere of the early Earth fortuitously trapped more heat from the sun. As the sun heated up, photosynthetic life began to take more carbon out of circulation and fill the atmosphere with relatively more oxygen. As Lovelock and Margulis put it in their 1973 paper, “Life at its origin can be considered to have fed on the blanket of gas which kept it warm. Its continued survival required the early development of the capacity to recognize potentially adverse changes and of processes which could oppose such changes.”
Earth keeping a relatively stable surface temperature across timescales of billions of years despite a heating sun was one of the clearest examples of potential planetary homeostasis the two scientists presented. Temperature regulation is crucial for all organisms since metabolic reactions run best only in particular ranges of temperatures (hence the vulnerability to hyper- and hypothermia when our own homeostatic mechanisms can’t keep up with extreme external conditions).
The theory of Gaia’s planetary temperature regulation reframes how we understand the recent influx of greenhouse gases into the atmosphere due to human reliance on fossil fuels. From the Gaian point of view, human beings are disrupting ancient Gaian homeostasis and thermodynamic regulation by rapidly altering proportions of natural gases. If the planet and biosphere form a homeostatic, living entity, how do we understand ourselves, a member species, behaving so out of step with the well-being of its greater superorganismic body?
The immediate analogies from biology are troubling, both scientifically and politically. Gaia theory could easily support a portrait of humanity as a parasite in the body of the Earth superorganism — or, considering that we humans emerged originally in Gaia and multiplied rapidly with immense destabilizing consequences, a cancer metastasizing throughout a multicellular organism.
Lovelock himself approached this wording in at least one of his early books: “Not so long ago it seemed that mankind was like a cancer on this planet. … We were growing unrestrictedly at the expense of the rest of life. … The danger is still there in places.”
However, he then pivoted to highlight human self-awareness: “The population no longer increases everywhere, industry is far more conscious of its effect on the environment, and there is above all growing public awareness of our situation. We might claim that the spread of information about our problems is leading to the development of new processes for controlling, if not solving, them.”
This emphasis on human awareness points to another view of our species enhanced by Gaia: humankind as an immature planetary nervous system. (The related concept of a global brain continues to generate attention.) In 1975, Lovelock and Sidney Epton concluded a piece on Gaia in the New Scientist with a striking passage attributing to humans the anticipatory capacity that animal nervous systems provide:
We are sure that man needs Gaia but could Gaia do without man? In man, Gaia has the equivalent of a central nervous system and an awareness of herself and the rest of the universe. Through man, she has a rudimentary capacity, capable of development, to anticipate and guard against threats to her existence. For example, man can command just about enough capacity to ward off a collision with a planetoid the size of Icarus. Can it then be that in the course of man’s evolution within Gaia he has been acquiring the knowledge and skills necessary to ensure her survival?
The vision of Earth as a living body makes our planetary identity oscillate between an out-of-control growth and a budding nervous system. Recently, Gaia theory has contributed to more familial depictions of humankind as a wayward child in dangerous conflict with a potentially unforgiving parent, with a Mother Nature. The last image suggests that human beings and societies are not just a member of Gaia but, through global interactions, may be differentiating from Gaia into a planetary system of scale and complexity comparable to the rest of life — that our planet may in fact be doubly alive.
The writer Archibald MacLeish said that at pivotal moments, poets can “invent the age” by “inventing the metaphor.” Thinkers from the Earth sciences have reintroduced us to ancient cosmic metaphors: worlds of harmonic spheres, immense forces and collective bodies. The prospects of a planetary identity in a planetary age may depend in part on whether concepts like the noosphere, Anthropocene and Gaia can offer a resonant symbolic dimension, giving us the myths and metaphors through which we re-articulate our relationships to each other, the living world and the Earth.