The Meaning of Human Existence (4 page)

The exact opposite is the case in poetry and the other creative arts. There metaphor is everything. The creative writer, composer, or visual artist conveys, often obliquely by abstraction or deliberate distortion, his own perceptions and the feelings he hopes to evoke—about something, about anything, real or imagined. He seeks to bring forth in an original way some truth or other about the human experience. He tries to pass what he
creates directly along the channel of human experience, from his mind to your mind. His work is judged by the power and beauty of its metaphors. He obeys a dictum ascribed to Picasso: art is the lie that shows us the truth.

Wildly searching, sometimes shocking in effect, the creative arts and much of the humanities scholarship analyzing them are nonetheless in an important sense just the same old story, with the same themes, the same archetypes, the same emotions. We readers don’t care. We’re addicted to anthropocentricity, bound to a bottomless fascination with ourselves and others of our kind. Even the best-educated live on an ad libitum diet of novels, movies, concerts, sports events, and gossip all designed to stir one or more of the relatively small range of emotions that diagnose
Homo sapiens
. Our stories about animals require human-like emotions and behavior understandable with well-worn guidebooks of human nature. We use endearing animal caricatures, including even those of tigers and other ferocious predators, to teach children about other people.

We are an insatiably curious species—provided the subjects are our personal selves and people we know or would like to know. The behavior goes far back beyond our species in the evolution of the primate family tree. It has been observed, for example, that when caged monkeys are allowed to look outside at a variety
of other objects, their first choice for attention is other monkeys.

The function of anthropocentricity—fascination about ourselves—is the sharpening of social intelligence, a skill in which human beings are the geniuses among all Earth’s species. It arose dramatically in concert with the evolution of the cerebral cortex during the origin of
Homo sapiens
from the African australopith prehumans. Gossip, celebrity worship, biographies, novels, war stories, and sports are the stuff of modern culture because a state of intense, even obsessive concentration on others has always enhanced survival of individuals and groups. We are devoted to stories because that is how the mind works—a never-ending wandering through past scenarios and through alternative scenarios of the future.

If gods of the ancient Greek tradition were watching, they would view human error the way we do in comedies and tragedies, but they might also feel empathy by viewing our foibles as flaws forced on us by Darwinian necessity. There is a parallel to gods and their human puppets in people watching kittens at play. The animals use three basic maneuvers suited to their future role as predators: to stalk and leap on a trailing string is practice for catching mice; to leap up to the string above and seize it with paws clapped together is for birds; and to scoop at a string near the feet is for fish or small prey at their feet.
It’s all amusing to us, but vital to them as a sharpening of survival skills.

Science builds and tests competitive hypotheses from partial evidence and imagination in order to generate knowledge about the real world. It is totally committed to fact without reference to religion or ideology. It cuts paths through the fever swamp of human existence.

You have of course heard of these qualities. But science has additional properties that distinguish it from the humanities. Of these the most important is the concept of the continuum. The idea of variation of entity and process occurring continuously in one, two, or more dimensions is so routine in most of physics and chemistry as to require no explicit mention. Continua include such familiar gradients as temperature, velocity, mass, wave length, particle spin, pH, and carbon-based molecular analogs. They become less obvious in molecular biology, where only a few basic variations in structure work to explain the function and reproduction of cells. They reappear forcefully in evolutionary biology and evolution-based ecology, which address the differing adaptations of millions of species to their respective environments. And they have returned with even greater flair and drama in studies of exoplanets.

Some nine hundred such planets had been discovered prior to the partial shutdown of the Kepler space telescope
in 2013, the shutdown due to the malfunction of an aiming device. The Kepler images were amazing even to generations who regarded flybys and soft landings on other planets in the Solar System as routine. They are also immensely important, the equivalent of a seaman’s first glimpse of a new continent’s coastline, and a shout of, Land! Land!, where none might have existed. An estimated hundred billion star systems make up the Milky Way galaxy, and astronomers believe that all are orbited by an average of at least one planet. A small but still substantial fraction are likely to harbor life-forms—even if the organisms are only microbes living under extremely hostile conditions.

The exoplanets (planets in other star systems) of the galaxy form a continuum. Astronomers have newly observed or at least inferred a bestiary of exoplanets more varied than anything previously imagined. There exist giant gas planets resembling Jupiter and Saturn, some hugely larger in volume. There are smaller rocky planets like our own, tiny specks orbiting at the right distance from the mother star to support life, fundamentally different from rocky planets at other distances (as Mercury and Venus are fatally near to the Sun and planetlike Pluto fatally far away). There exist planets that do not rotate, others that travel close to the mother star and then far away and back again in elliptical orbits.
There probably exist orphaned rogue planets, thrown loose from the gravitational pull of their mother stars, drifting through outer space. Some of the exoplanets also have an entourage of one or more moons. In addition to great and continuous variation in size, location, and orbit, there are comparable gradients in the chemical composition of the body and atmosphere of the planets and their moons, derived from the particularities of their origin.

Astronomers, being normal humans as well as scientists, are as awed as the rest of us by their discoveries. The discoveries affirm that Earth is not the center of the Universe—we’ve known that since Copernicus and Galileo—but just how far from the center has been hard to imagine. The tiny blue speck we call home is proportionately no more than that, a mote of stardust near the edge of our galaxy among a hundred billion or more galaxies in the universe. It occupies just one position in a continuum of planets, moons, and other planetlike heavenly bodies that we have just begun to understand. It would be becoming of us to speak modestly of our status in the cosmos. Let me offer a metaphor: Earth relates to the Universe as the second segment of the left antenna of an aphid sitting on a flower petal in a garden in Teaneck, New Jersey, for a few hours this afternoon.

With botany and entomology thus fleetingly brought
to mind, it is appropriate to introduce another continuum, the diversity of life in Earth’s biosphere. At the time of this writing (in 2013) there are 273,000 known species of plants in the living flora of Earth, a number expected to rise to 300,000 as more expeditions take to the field. The number of all known species of organisms on Earth, plants, animals, fungi, and microbes, is about 2 million. The actual number, combining known and unknown, is estimated to be at least three times that number, or more. The roster of newly described species is about 20,000 a year. The rate will certainly grow, as a multitude of still poorly explored tropical forest fragments, coral reefs, seamounts, and uncharted ridges and canyons of the deep ocean floor become better known. The number of described species will accelerate even faster with exploration of the largely unknown microbial world, now that the technology needed for the study of extremely small organisms has become routine. There will come to light strange new bacteria, archaeans, viruses, and picozoans that still swarm unseen everywhere on the surface of the planet.

As the census of species proceeds, other continua of biodiversity are being mapped. They include the unique biology of each living species and the long, winding processes of evolution that created it. Part of the end product is the gradient of size across a dozen orders of magnitude.
It ranges from the blue whale and African elephant down to superabundant photosynthetic bacteria and scavenging picozoans of the sea, the latter so small they cannot be studied with ordinary light microscopy.

Of all the continua mapped by science, the most relevant to the humanities are the senses, which are extremely limited in our species. Vision is based in
Homo sapiens
on an almost infinitesimal sliver of energy, four hundred to seven hundred nanometers in the electromagnetic spectrum. The rest of the spectrum, saturating the Universe, ranges from gamma rays trillions of times shorter than the human visual segment to radio waves trillions of times longer. Animals live within their own slivers of continua. Below four hundred nanometers, for example, butterflies find pollen and nectar in flowers by the patterns of ultraviolet light reflected off the petals—patterns and colors unseen by us. Where we see a yellow or red blossom, the insects see an array of spots and concentric circles in light and dark.

Healthy people believe intuitively that they can hear almost every sound. However, our species is programmed to detect only twenty to twenty thousand hertz (cycles of air compression per second). Above that range, flying bats broadcast ultrasonic pulses into the night air and listen for the echoes to dodge obstacles and snatch moths and other insects on the wing. Below the human range,
elephants rumble complex messages in exchanges back and forth with other members of their herd. We walk through nature like a deaf person on the streets of New York, sensing only a few vibrations, able to interpret almost nothing.

Human beings have one of the poorest senses of smell of all the organisms on Earth, so weak that we have only a tiny vocabulary to express it. We depend heavily on similes such as “lemony” or “acidic” or “fetid.” In contrast, the vast majority of other organisms, ranging in kind from bacteria to snakes and wolves, rely on odor and taste for their very existence. We depend on the sophistication of trained dogs to lead us through the olfactory world, tracking individual people, detecting even the slightest trace of explosives and other dangerous chemicals.

Our species is almost wholly unconscious of certain other kinds of stimuli without the use of instruments. We detect electricity solely by a tingle, a shock, or a flash of light. In contrast, there exist a variety of freshwater eels, catfish, and elephant-nose fish, confined to murky water where, deprived of vision, they live instead in a galvanic world. They generate charged fields around their bodies with trunk muscle tissue that has been modified by evolution into organic batteries. With the aid of electric shadows in the pattern of charges, the fish avoid
obstacles around them, locate prey, and communicate with others of the same species. Yet another part of the environment beyond the reach of humans is Earth’s magnetic field, used by some migratory birds to guide them during their long-distance journeys.

The exploration of continua allows humanity to measure the dimensions of the real cosmos, from the infinite ranges of size, distance, and quantity, in which we and our little planet exist. The scientific enterprise suggests where to look for previously unexpected phenomena, and how to perceive the whole of reality by a measurable webwork of cause-and-effect explanation. By knowing the position of each phenomenon in the relevant continua—relevant continua in ordinary parlance being the variable of each system—we have learned the chemistry of the surface of Mars; we know approximately how and when the first tetrapods crawled out of ponds onto the land; we can predict conditions in both the infinitesimal and near-infinite by the unified theory of physics; and we can watch blood flow and nerve cells in the human brain light up during conscious thought. In time, likely no more than several decades, we will be able to explain the dark matter of the Universe, the origin of life on Earth, and the physical basis of human consciousness during changes of mood and thought. The invisible is seen, the vanishingly small weighed.

So, what has this explosive growth of scientific knowledge to do with the humanities?
Everything
. Science and technology reveal with increasing precision the place of humanity, here on Earth and beyond in the cosmos as a whole. We occupy a microscopic space in each of the relevant continua that might have produced a species of human-grade intelligence anywhere, here and on other planets. Our ancestral species, traced further and further back through a series of ever more primitive life-forms, are all lucky lottery winners that stumbled their way through the labyrinth of evolution.

We are a very special species, perhaps the chosen species if you prefer, but the humanities by themselves cannot explain why this is the case. They don’t even pose the question in a manner that can be answered. Confined to a small box of awareness, they celebrate the tiny segments of the continua they know, in minute detail and over and over again in endless permutations. These segments alone do not address the origins of the traits we fundamentally possess—our overbearing instincts, our moderate intelligence, our dangerously limited wisdom, even, critics will insist, the hubris of our science.

The first Enlightenment was undertaken more than four centuries ago when science and the humanities both were elementary enough to make their symbiosis look feasible. It became possible with the opening of the
global sea routes by Western Europe from the late fifteenth century onward. The circumnavigation of Africa and the discovery of the New World led to new, global trade routes and expanded military conquest. The new, global reach was a turning point in history that placed a premium on knowledge and invention. Now we are launched into a new cycle of exploration—infinitely richer, correspondingly more challenging, and not by coincidence increasingly humanitarian. It is within the power of the humanities and the serious creative arts within them to express our existence in ways that begin at last to realize the dreams of the Enlightenment.