Lives of a Cell

by Lewis Thomas

  We work at this all our lives, and collectively we give it life, but we do not exert the least control over language, not as individuals or committees or academies or governments. Language, once it comes alive, behaves like an active, motile organism. Parts of it are always being changed, by a ceaseless activity to which all of us are committed; new words are invented and inserted, old ones have their meaning altered or abandoned. New ways of stringing words and sentences together come into fashion and vanish again, but the underlying structure simply grows, enriches itself, expands. Individual languages age away and seem to die, but they leave progeny all over the place. Separate languages can exist side by side for centuries without touching each other, maintaining their integrity with the vigor of incompatible tissues. At other times, two languages may come together, fuse, replicate, and give rise to nests of new tongues.

  If language is at the core of our social existence, holding us together, housing us in meaning, it may also be safe to say that art and music are functions of the same universal, genetically determined mechanism. These are not bad things to do together. If we are social creatures because of this, and therefore like ants, I for one (or should I say we for one?) do not mind.

  INFORMATION

  According to the linguistic school currently on top, human beings are all born with a genetic endowment for recognizing and formulating language. This must mean that we possess genes for all kinds of information, with strands of special, peculiarly human DNA for the discernment of meaning in syntax. We must imagine the morphogenesis of deep structures, built into our minds, for coding out, like proteins, the parts of speech. Correct grammar (correct in the logical, not fashionable, sense) is as much as biologic characteristic of our species as feathers on birds.

  If this is true, it would mean that the human mind is preset, in some primary sense, to generate more than just the parts of speech. Since everything else that we recognize as human behavior derives from the central mechanism of language, the same sets of genes are at least indirectly responsible for governing such astonishing behavior as in the concert hall, where hundreds of people crowd together, silent, head-tilted, meditating, listening to music as though receiving instructions, or in a gallery, moving along slowly, peering, never looking at each other, concentrating as though reading directions.

  This view of things is compatible with the very old notion that a framework for meaning is somehow built into our minds at birth. We start our lives with templates, and attach to them, as we go along, various things that fit. There are neural centers for generating, spontaneously, numberless hypotheses about the facts of life. We store up information the way cells store energy. When we are lucky enough to find a direct match between a receptor and a fact, there is a deep explosion in the mind; the idea suddenly enlarges, rounds up, bursts with new energy, and begins to replicate. At times there are chains of reverberating explosions, shaking everything: the imagination, as we say, is staggered.

  This system seems to be restricted to human beings, since we are the only beings with language, although chimpanzees may have the capability of manipulating symbols with a certain syntax. The great difference between us and the other animals may be the qualitative difference made by speech. We live by making transformations of energy into words, storing it up, and releasing it in controlled explosions.

  Speechless animals cannot do this sort of thing, and they are limited to single-stage transactions. They wander, as we do, searching for facts to fit their sparser stock of hypotheses, but when the receptor meets its match, there is only a single thud. Without language, the energy that is encoiled, springlike, inside information can only be used once. The solitary wasp, Sphex, nearing her time of eggs, travels aloft with a single theory about caterpillars. She is, in fact, a winged receptor for caterpillars. Finding one to match the hypothesis, she swoops, pins it, paralyzes it, carries it off, and descends to deposit it precisely in front of the door of the round burrow (which, obsessed by a different version of the same theory, she had prepared beforehand). She drops the beast, enters the burrow, inspects the interior for last-minute irregularities, then comes out to pull it in for the egg-laying. It has the orderly, stepwise look of a well thought-out business. But if, while she is inside inspecting, you move the caterpillar a short distance, she has a less sensible second thought about the matter. She emerges, searches for a moment, finds it, drags it back to the original spot, drops it again, and runs inside to check the burrow again. If you move the caterpillar again, she will repeat the program, and you can keep her totally preoccupied for as long as you have the patience and the heart for it. It is a compulsive, essentially neurotic kind of behavior, as mindless as an Ionesco character, but the wasp cannot imagine any other way of doing the thing.

  Lymphocytes, like wasps, are genetically programmed for exploration, but each of them seems to be permitted a different, solitary idea. They roam through the tissues, sensing and monitoring. Since there are so many of them, they can make collective guesses at almost anything antigenic on the surface of the earth, but they must do their work one notion at a time. They carry specific information in their surface receptors, presented in the form of a question: is there, anywhere out there, my particular molecular configuration? It seems to be in the nature of biologic information that it not only stores itself up as energy but also instigates a search for more. It is an insatiable mechanism.

  Lymphocytes are apparently informed about everything foreign around them, and some of them come equipped for fitting with polymers that do not exist until organic chemists synthesize them in their laboratories. The cells can do more than predict reality; they are evidently programmed with wild guesses as well.

  Not all animals have lymphocytes with the same range of information, as you might expect. As with language, the system is governed by genes, and there are genetic differences between species and between inbred animals of the same species. There are polymers that will fit the receptors of one line of guinea pigs or mice but not others; there are responders and nonresponders.

  When the connection is made, and a particular lymphocyte with a particular receptor is brought into the presence of the particular antigen, one of the greatest small spectacles in nature occurs. The cell enlarges, begins making new DNA at a great rate, and turns into what is termed, appropriately, a blast. It then begins dividing, replicating itself into a new colony of identical cells, all labeled with the same receptor, primed with the same question. The new cluster is a memory, nothing less.

  For this kind of mechanism to be useful, the cells are required to stick precisely to the point. Any ambiguity, any tendency to wander from the matter at hand, will introduce grave hazards for the cells, and even more for the host in which they live. Minor inaccuracies may cause reactions in which neighboring cells are recognized as foreign, and done in. There is a theory that the process of aging may be due to the cumulative effect of imprecision, a gradual degrading of information. It is not a system that allows for deviating.

  Perhaps it is in this respect that language differs most sharply from other biologic systems for communication. Ambiguity seems to be an essential, indispensable element for the transfer of information from one place to another by words, where matters of real importance are concerned. It is often necessary, for meaning to come through, that there be an almost vague sense of strangeness and askewness. Speechless animals and cells cannot do this. The specifically locked-on antigen at the surface of a lymphocyte does not send the cell off in search of something totally different; when a bee is tracking sugar by polarized light, observing the sun as though consulting his watch, he does not veer away to discover an unimaginable marvel of a flower. Only the human mind is designed to work in this way, programmed to drift away in the presence of locked-on information, straying from each point in a hunt for a better, different point.

  If it were not for the capacity for ambiguity, for the sensing of strangeness, that words in all languages provide, w
e would have no way of recognizing the layers of counterpoint in meaning, and we might be spending all our time sitting on stone fences, staring into the sun. To be sure, we would always have had some everyday use to make of the alphabet, and we might have reached the same capacity for small talk, but it is unlikely that we would have been able to evolve from words to Bach. The great thing about human language is that it prevents us from sticking to the matter at hand.

  DEATH IN THE OPEN

  Most of the dead animals you see on highways near the cities are dogs, a few cats. Out in the countryside, the forms and coloring of the dead are strange; these are the wild creatures. Seen from a car window they appear as fragments, evoking memories of woodchucks, badgers, skunks, voles, snakes, sometimes the mysterious wreckage of a deer.

  It is always a queer shock, part a sudden upwelling of grief, part unaccountable amazement. It is simply astounding to see an animal dead on a highway. The outrage is more than just the location; it is the impropriety of such visible death, anywhere. You do not expect to see dead animals in the open. It is the nature of animals to die alone, off somewhere, hidden. It is wrong to see them lying out on the highway; it is wrong to see them anywhere.

  Everything in the world dies, but we only know about it as a kind of abstraction. If you stand in a meadow, at the edge of a hillside, and look around carefully, almost everything you can catch sight of is in the process of dying, and most things will be dead long before you are. If it were not for the constant renewal and replacement going on before your eyes, the whole place would turn to stone and sand under your feet.

  There are some creatures that do not seem to die at all; they simply vanish totally into their own progeny. Single cells do this. The cell becomes two, then four, and so on, and after a while the last trace is gone. It cannot be seen as death; barring mutation, the descendants are simply the first cell, living all over again. The cycles of the slime mold have episodes that seem as conclusive as death, but the withered slug, with its stalk and fruiting body, is plainly the transient tissue of a developing animal; the free-swimming amebocytes use this organ collectively in order to produce more of themselves.

  There are said to be a billion billion insects on the earth at any moment, most of them with very short life expectancies by our standards. Someone has estimated that there are 25 million assorted insects hanging in the air over every temperate square mile, in a column extending upward for thousands of feet, drifting through the layers of the atmosphere like plankton. They are dying steadily, some by being eaten, some just dropping in their tracks, tons of them around the earth, disintegrating as they die, invisibly.

  Who ever sees dead birds, in anything like the huge numbers stipulated by the certainty of the death of all birds? A dead bird is an incongruity, more startling than an unexpected live bird, sure evidence to the human mind that something has gone wrong. Birds do their dying off somewhere, behind things, under things, never on the wing.

  Animals seem to have an instinct for performing death alone, hidden. Even the largest, most conspicuous ones find ways to conceal themselves in time. If an elephant missteps and dies in an open place, the herd will not leave him there; the others will pick him up and carry the body from place to place, finally putting it down in some inexplicably suitable location. When elephants encounter the skeleton of an elephant out in the open, they methodically take up each of the bones and distribute them, in a ponderous ceremony, over neighboring acres.

  It is a natural marvel. All of the life of the earth dies, all of the time, in the same volume as the new life that dazzles us each morning, each spring. All we see of this is the odd stump, the fly struggling on the porch floor of the summer house in October, the fragment on the highway. I have lived all my life with an embarrassment of squirrels in my backyard, they are all over the place, all year long, and I have never seen, anywhere, a dead squirrel.

  I suppose it is just as well. If the earth were otherwise, and all the dying were done in the open, with the dead there to be looked at, we would never have it out of our minds. We can forget about it much of the time, or think of it as an accident to be avoided, somehow. But it does make the process of dying seem more exceptional than it really is, and harder to engage in at the times when we must ourselves engage.

  In our way, we conform as best we can to the rest of nature. The obituary pages tell us of the news that we are dying away, while the birth announcements in finer print, off at the side of the page, inform us of our replacements, but we get no grasp from this of the enormity of scale. There are 3 billion of us on the earth, and all 3 billion must be dead, on a schedule, within this lifetime. The vast mortality, involving something over 50 million of us each year, takes place in relative secrecy. We can only really know of the deaths in our households, or among our friends. These, detached in our minds from all the rest, we take to be unnatural events, anomalies, outrages. We speak of our own dead in low voices; struck down, we say, as though visible death can only occur for cause, by disease or violence, avoidably. We send off for flowers, grieve, make ceremonies, scatter bones, unaware of the rest of the 3 billion on the same schedule. All of that immense mass of flesh and bone and consciousness will disappear by absorption into the earth, without recognition by the transient survivors.

  Less than a half century from now, our replacements will have more than doubled the numbers. It is hard to see how we can continue to keep the secret, with such multitudes doing the dying. We will have to give up the notion that death is catastrophe, or detestable, or avoidable, or even strange. We will need to learn more about the cycling of life in the rest of the system, and about our connection to the process. Everything that comes alive seems to be in trade for something that dies, cell for cell. There might be some comfort in the recognition of synchrony, in the information that we all go down together, in the best of company.

  NATURAL SCIENCE

  The essential wildness of science as a manifestation of human behavior is not generally perceived. As we extract new things of value from it, we also keep discovering parts of the activity that seem in need of better control, more efficiency, less unpredictability. We’d like to pay less for it and get our money’s worth on some more orderly, businesslike schedule. The Washington planners are trying to be helpful in this, and there are new programs for the centralized organization of science all over the place, especially in the biomedical field.

  It needs thinking about. There is an almost ungovernable, biologic mechanism at work in scientific behavior at its best, and this should not be overlooked.

  The difficulties are more conspicuous when the problems are very hard and complicated and the facts not yet in. Solutions cannot be arrived at for problems of this sort until the science has been lifted through a preliminary, turbulent zone of outright astonishment. Therefore, what must be planned for, in the laboratories engaged in the work, is the totally unforeseeable. If it is centrally organized, the system must be designed primarily for the elicitation of disbelief and the celebration of surprise.

  Moreover, the whole scientific enterprise must be arranged so that the separate imaginations in different human minds can be pooled, and this is more a kind of game than a systematic business. It is in the abrupt, unaccountable aggregation of random notions, intuitions, known in science as good ideas, that the high points are made.

  The most mysterious aspect of difficult science is the way it is done. Not the routine, not just the fitting together of things that no one had guessed at fitting, not the making of connections; these are merely the workaday details, the methods of operating. They are interesting, but not as fascinating as the central mystery, which is that we do it at all, and that we do it under such compulsion.

  I don’t know of any other human occupation, even including what I have seen of art, in which the people engaged in it are so caught up, so totally preoccupied, so driven beyond their strength and resources.

  Scientists at work have th
e look of creatures following genetic instructions; they seem to be under the influence of a deeply placed human instinct. They are, despite their efforts at dignity, rather like young animals engaged in savage play. When they are near to an answer their hair stands on end, they sweat, they are awash in their own adrenalin. To grab the answer, and grab it first, is for them a more powerful drive than feeding or breeding or protecting themselves against the elements.

  It sometimes looks like a lonely activity, but it is as much the opposite of lonely as human behavior can be. There is nothing so social, so communal, so interdependent. An active field of science is like an immense intellectual anthill; the individual almost vanishes into the mass of minds tumbling over each other, carrying information from place to place, passing it around at the speed of light.

  There are special kinds of information that seem to be chemotactic. As soon as a trace is released, receptors at the back of the neck are caused to tremble, there is a massive convergence of motile minds flying upwind on a gradient of surprise, crowding around the source. It is an infiltration of intellects, an inflammation.

  There is nothing to touch the spectacle. In the midst of what seems a collective derangement of minds in total disorder, with bits of information being scattered about, torn to shreds, disintegrated, reconstituted, engulfed, in a kind of activity that seems as random and agitated as that of bees in a disturbed part of the hive, there suddenly emerges, with the purity of a slow phrase of music, a single new piece of truth about nature.