By Michael Timm
"Grown-ups never understand anything by themselves, and it is tiresome for children to be always and forever explaining things to them."
—Antoine de Saint Exupéry
I asked my 4-year-old nephew what life was the other day.
"Living?" he answered, not, I suspect, entirely understanding the question.
"Living?" I said, not entirely understanding the answer.
He laughed, perhaps tickled to be the authority on the matter, then added that he thought they had something that explained what life was at Disney. He and his family are trekking to Walt Disney World this fall. It will already be the second time he will make the cultural pilgrimage during his young life. Maybe he will find out.
What is life?
I don't know. I didn't used to not know. There was a time that the answer seemed pretty intuitive. I recall coursework in grade school biology, wherein the attributes of life were laid out in neat bullet points. I don't have that textbook anymore, and I may be recalling incorrectly, but I think the necessary and sufficient conditions for something to be termed life were as follows: 1. It has metabolism. 2. It reproduces. Of course, metabolism was explained more along the lines of animal life: It moves, it grows, it sleeps, it eats, it poops, it dies. Reproduction was idealized, saving youngsters the gritty details of the conjugal visits of slugs (thanks to Jenny Hauf for the link), the complexities of Punnett Square pea plant crossbreeding, or hot sex (needless to say the textbook camera panned away into smoldering fire far before any human mating rituals were thoroughly examined, thwarting the juvenile compulsion to flip to the back the book at the beginning of a term, an investigation rewarded only with sterile diagrams of bodies whose muscles and skin had been photographically autopsied so that the inner tubes and eerie symmetry of two testicles and two ovaries suggested no real clue as to whence babies came. At my school, and no doubt thousands others, one of the recess activities that defined the status of young males in the pecking order was who could yell "PENIS!" the loudest and at the most inopportune times. Perhaps this was partly the result of our anatomical ignorance. Or our existential self-knowledge, demanding to erupt into the world, to be claimed out loud before a hostile social world that clothed and ruled and confused and lied. Popular adult culture, however, sums the cause up in one all-too-tidy word: adolescence.).
As a young student, I recall resisting these definitions of life—metabolism, reproduction—not because they didn't make sense, but because it seemed too obvious what life was, didn't it? My chair was not alive; I was. My pencil wasn't alive; something in my boogers probably was. Plants were alive; dead plants weren't. If anything, the definition seemed dangerously exclusionary: If I stopped pooping, or stopped eating, or never reproduced, was I not alive? Reading more closely, perhaps, I'm sure I discovered that what was alive must be capable of metabolizing, must be capable of reproduction. If that was the case, then how did we really know about anything? What if we weren't appreciating a certain system at the proper scale to be able to understand that it actually was metabolizing, was reproducing—only across a scale so incomparable to human scales that its behavior approximated inanimate stasis or frenzied chaos? And, who had gone out and stuck the flag in the ground to say what life was and life wasn't? From an early age, this distinction also seemed suspect, although I wouldn't then have described it as a sensitivity to the politics of scientific classification. I don't know that it's fair even now to make that claim, but the arbitrariness of the defining characteristics remains significant in my view.
I understand and appreciate that we need categories and definitions and systems to get anything done, however, and so I accept metabolism and reproduction as fair criteria for life, or at least the best at our disposal based on the accessible biosphere. Today I accept these criteria also out of sheer amazement, and with an additional understanding that I believe is also usually imparted to the criteria—life is something which self-metabolizes, which self-reproduces (I believe the technical term is that life is an autocatalytic system). Life, in this sense, does not need someone to turn on the electricity to go spinning off across the floor, lights whirring. Life is a system that survives. What is alive doesn't always survive, but life is intrinsically motivated by and created by survival.
If that's true, is anything other than life also so motivated and created? In other words, are we really saying anything at all useful with such a claim or is it akin to mathematical identity, that 1 equals 1? Fascinatingly, at least to me, it seems there are other systems that behave the way life would/does, if accurately characterized as a system intrinsically motivated and created by survival. The connections are not rock solid, but narratives, information, and consciousness may also behave this way. (See also my somewhat dubious and definitely dense discussion comparing information and life via analogy, and speculating at extending this analogy onto broader scales. "Musings on Information," Timm: 2005.)
The other amazing aspect about life is that it's not fair to say it survives on its own—life processes what is not alive and reconstitutes it as part of what is alive. This is another way of saying that ecological systems and food webs exist, that plants photosynthesize sunlight and cycle nitrogen, that animals respire, that fungi decompose, that we're all made of matter churned out of stars, fueled by nuclear energy radiated away from our nearest star, that the atoms and molecules deep inside the rocks of this planet and the atoms and molecules in our bones and brains are geologically regurgitated cousins. Okay, fine. Maybe that doesn't stir your inner core like a compelling member of the opposite sex. But consider the philosophical ramifications of this biological reality: Life is not made of any different stuff than nonlife—what seems to distinguish life, instead, is the active patterns operating on or with or through the raw materials. Life is a spectrum of opportunistic patterns.
If that's true—if biological life's actual definition is not constrained by matter or energy type but by the function and operation of a certain kind of pattern (self-metabolizing and reproducing) then such an answer about what is life implicitly widens the possible limits of the spectrum of matter and energy generally understood to participate with life patterns. Basically, I'm deemphasizing the chemical properties of life systems for this definition of life and emphasizing the qualities of the defining characteristics themselves—self-metabolism and reproduction. If these characteristics aren't appropriate as defining characteristics, then the discussion that follows will fail. They are, after all, human-created characteristics and not stamped anywhere in the mathematics or mythos of the cosmos. But let's assume self-metabolism and reproduction are analogous with those systems we identify as alive and that what we identify is actually in some special or significant way life.
Thus, we look for water on Mars because terrestrial life as we know it, to paraphrase Mr. Spock, likes water. To find signs of life as we know it, this approach is appropriately logical. But if life as we know it is really just a code for terrestrial carbon-based biological life, while what we really understand life to be is a pattern that self-metabolizes and reproduces, perhaps the net is cast too shallowly. Perhaps additional living systems are superimposed upon our own mundane experience, invisible because we are not trained to observe for their signs; perhaps we are embedded within vaster living systems metabolizing and reproducing on geological or other scales.
James Lovelock's idea of Gaia, Earth as superorganism, comes to mind. So does Daoism, in its appreciation of li, a pattern infusing and invigorating all things, making them what they are but also suffusing structure as though with energy.
Within a purist scientific paradigm, the above are all just crazy ideas if they can't make predictions to position themselves for empirical substantiation. (Though it's possible that some forms of life would, could, or do evade our empirical observation. We would require a compelling non-empirical reason to believe in the existence of such life, and so I will not speculate further about such life in this paragraph. However, for those opportunistic patterns operating on scales significantly larger than those commonly understood as living, we ought to be able to compare them by analogy to systems operating on smaller more intelligible scales—provided someone can intuitively collect the appropriate parts to relate to the appropriate wholes.)
Others have written about other autocatalytic systems: economic markets, computer programs, ecosystems.
Personally, I am attracted to the idea that lightning storms are in some manner components of a living system. I cannot offer any scientific basis for this connection, but I sense that there hides meaning in analogy between neurobioelectrical systems and the planet's roving electrical storms. Each depends upon and is composed by rapid, apparently unpredictable electromagnetic signals; each system arises from or gives way to some degree of spontaneity. Storms are characteristics of (all the?) planets with an atmosphere, so they are observably more widespread than terrestrial biological life and they seem to favor or depend upon regions of instability—areas at gradient thresholds where one thing comes into contact with something else (i.e. shorelines, cloud boundary layers, deep ocean vents, the thin biosphere itself)—much like biological life we know. And although observable, storms' behavior and origination cannot be accurately predicted or completely described; this evokes, to me, our similar failures to understand the behaviors and origination of the electrical workings of animal brains and how those electrical signals are connected to thought and behavior. Poetically, this relationship raises the question of scale in a novel way: Are we humans perhaps situated quasi-ignorantly within a component of something like a macroorganism or macroorganelle, something far vaster than our own experience?
In isolation, comments like these are pure speculation, but it feels to me as though we humans already are networking ourselves together into such macroorganisms—at least culturally, politically, and technologically—operating atop the natural and biological world as though new forms of life upon a nonliving surface. That's what I think fascinates archaeologists about the nature of state formation—not the dusty ruins of temple pyramids, but the processes that led a bunch of people to dramatically shift their behavior within a finite geographic boundary, integrating into a sociopolitical entity that behaves like a cell. Also fascinating, consequently, are the processes that lead to state disintegration. But we humans already organize ourselves into macroorganisms—corporations, cities, nation-states just to name the obvious ones…so it should not be so much of a leap to ponder what other possibly living or lifelike systems of which we may be a part.
Although it is counterintuitive, while reflecting for this essay the thought occurred to me that perhaps there is no life—that nothing is alive. That is, what if there is no actual distinction between life and nonlife, only a human line in the sand across the spectrum of all reality? We humans are great category-makers, and perhaps one day we will be insightful enough to realize this distinction as the greatest false dichotomy of them all. (Though I have not read him deeply, this view seems somewhat resonant with the ideas of Ken Wilber with regard to the nature of consciousness. Wilber supposes that consciousness exists along a spectrum, borrowing the concept from the electromagnetic spectrum, and that it varies in quality but not in kind in and across all existence.) Rather than allow this perception excuse moral mismanagement, however—a la, Life is special, therefore life deserves special treatment; if there is no life, then nothing deserves special treatment—it seems to me to suppose the opposite: fewer barriers imply deeper sameness and therefore warrant more and better care. In this sense, nothing is alive equates with everything is alive. Either would be an accurate consequence of removing the label of life/nonlife, and the decision not to differentiate would be most telling and most appropriate at those hazy boundaries we already understand to some extent, but have a hard time delineating.
Mathematician and theoretical physicist Freeman Dyson, in his excellent and fascinating Origins of Life (1999), grapples with one of these boundaries, namely, the boundary between nonliving systems and life. He addresses the question of how life came to be. Dyson frames the discussion in terms of which biological function came first: replication or metabolism, since it seems that life as we know it depends upon both of these processes coupled together. Based on its greater resilience and the greater likelihood that it could happen on its own, he supposes that metabolism probably happened first, and lasted long enough to become coupled with the less "error-tolerant" processes of replication:
Organisms specializing in replication tend to be parasites, and molecular biologists prefer parasites for experimental study because parasites are structurally simpler than their hosts and better suited to quantitative manipulation. In the balance of nature there must be an opposite bias. Hosts must exist before there can be parasites. Somebody must eat and grow to provide a home for those who only reproduce. In the world of microbiology, as in the world of human society and economics, we cannot all be parasites. (Dyson, 1999: 9)
A brief detour is necessary before returning to Dyson's discussions of life's origins. In several books, including Acquiring Genomes: The Theory of the Origins of the Species (2003), microbiologist Lynn Margulis and her son (by Carl Sagan) Dorion Sagan advance and defend the idea of symbiogenesis—that organisms evolve together symbiotically and actually speciate into new organisms comprised of cooperating groups or relationships of organisms. Some of the case studies they offer are fascinating: photosynthetic slugs and agricultural termites are among the more exotic, but their discussion of the specialized bacteria within cow guts also bring the realities of symbiosis—and the tantalizing prospects of symbiogenesis—home to the reader in an almost Zen Buddhist manner: there is no cow.
Margulis and Sagan sum up:
The agents of evolutionary change tend to be fully alive organisms, microbes, and their ecological relations, not just the random mutations these microbes have inside them. The formation and diversification of any new species is the outward manifestation of the actions of subvisible forms of life: the smallest microbes, bacteria, their larger descendants, the larger microbes, protists, and fungi, along with their intracellular legacies, organelles such as mitochondria and centrioles. Evolution emerges from the fact that these small living organisms and their progeny tend to outgrow their bounds.
Dyson, in contemplating the possibilities for life's origins, adapts Margulis' idea of symbiogenesis. He supposes that the replicative functions (chemically predisposed to utilize nucleic acids because of their molecular structure) started up within or around metabolizing structures, possibly synthesizing nucleic acids from the waste products of protein metabolism within oily bubbles that have been demonstrated to be able to form in the absence of life processes. He develops a mathematical model that supposes a "garbage-bag world," originally described by Soviet scientist Aleksander Oparin in 1924, where metabolizing protocells only reproduce statistically but where natural selection eventually improves the efficiency of the metabolic processes. Eventually, a symbiosis between replicating and metabolizing processes developed and from this fusion of processes, a cell was born. If the ideas behind Dyson's "toy model," analogous by his own admission to a logical just-so story, are ever substantiated by experimentation, it might help bridge the conceptual gap—at least chemically and physically—between life and non-life.
As I am not bound here by the rigors of scientific inquiry, I would argue that the phenomenon of life as an opportunistic pattern does not depend upon the medium in which the pattern operates (biological structures are convenient media but theoretically not essential to the message). This view might change what patterns we would identify as living, but I think it would be a better line to draw in the sand if we must, as we probably should, draw a line.
I will close by quoting from biologist and writer Lewis Thomas, a brilliant man whose words I only recently discovered. Each of his essays is a tidy and farsighted gem. Here is some wisdom from the introductory essay of his 1974 book of essays, The Lives of a Cell: Notes of a Biology Watcher:
…it is illusion to think that there is anything fragile about the life of the earth; surely this is the toughest membrane imaginable in the universe, opaque to probability, impermeable to death. We are the delicate part, transient and vulnerable as cilia…Man is embedded in nature.
The biologic science of recent years has been making this a more urgent fact of life. The new, hard problem will be to cope with the dawning, intensifying realization of just how interlocked we are. (Thomas, 1974: 3)
We humans are, perhaps, in our own phase of childhood, only beginning to realize, like my nephew, what life may be, the possibilities ahead.
But we can take some solace in Margulis. For though couching life in thermodynamic terms seems cold and mechanical, there may be a philosophical silver lining in such an approach. In the tradition of Erwin Schödinger, Margulis and Sagan describe life in thermodynamic terms—as a system operating by the same principles as tornadoes and hurricanes. They argue life is a gradient-reducing system, and, that, across the broadest cosmic scales, even though entropy holds sway in our known universe, an ever-expanding universe provides no end of gradients for life to reduce…
Michael Timm is a freelance writer. He has written and is in the process of revising a novel, The Philosopher of Milwaukee. He writes news and features for the Bay View Compass newspaper, of which he has been the assistant editor since 2005. His writing has also appeared in the Riverwest Currents, Shepherd Express, and Wisconsin Trails magazine. He earned his B.A. at Ripon College in Ripon, Wis., in 2004 studying both Anthropology and English. His totem animal is the platypus.
