This article focuses on the publication of Darwin’s final book (1881) in the context of Darwin’s larger attempts to resist the habitual anthropocentrism of human beings. It begins with Darwin’s discussion of animal cognition and the senses of worms. It concludes with his emphasis on the significant effects worm digestion has on the landscape and the fertility of the earth. The article links Darwin’s Worms Edwin Abbott’s 1884 novella Flatland, arguing that both texts are engaged in dismantling human perceptions that stem from possessing a highly visual brain, and that both throw doubt on the belief that a single objective world exists independent of particular observers.
On 10 October 1881 Charles Darwin published his final book, The Formation of Vegetable Mould, through the Action of Worms, with Observations on their Habits [hereafter Worms], based on extensive study of the behavior of worms and the effects that they have on the earth’s surface. The book is a testament to the extraordinary work of ordinary earthworms—millions of them—that process and smooth the turf. “It may be doubted,” Darwin writes, “whether there are many other animals which have played so important a part in the history of the world, as have these lowly organised creatures” (313). Worms begins with the individual physiology and behavior of worms before moving to the cumulative effects of their work on the exterior world. Two long chapters on their senses and habits are followed by four chapters cataloguing the results of their labor, including bringing up earth, burying buildings, enriching the soil, and denuding the land.
This treatise on worms represents neither a new subject for Darwin, nor a marked shift in his larger intellectual commitments. The father of evolutionary biology was as invested in earthworms as he was in human beings. Darwin had been fascinated by the mental and physical powers of tiny beings since at least the 1830s. His 1881 Worms is an expansion of a much shorter paper Darwin had presented to the Geological Society as early as 1837 on “The Formation of Mould,” just a year after he returned from his voyage on the Beagle. Over decades of observation and argument he had been urging his readers not to overvalue human thought and activity. Aside from the accident of it occurring six months before Darwin’s death, then, the publication of Worms does not represent a sharply delineated intellectual event in Darwin’s life.
Instead, placing Worms within a BRANCH timeline enables us to identify three gradual but crucial challenges that this book presents to anthropocentric attitudes in late-nineteenth-century science and intellectual history. Darwin’s Worms is a culmination of several transformations in thinking occurring at this time: 1) evolving scientific attitudes toward animal perception and cognition; 2) emerging ideas about the multi-dimensionality of space; and 3) a loss of confidence in progressivism as an organizing principle of change. As Oliver Sacks notes, this is a moment in which scientists studying animal behavior are not scorned for considering that there might be “any inner processes between stimulus and response”; that animals might, in other words, have some kind of subjective experiences (5). On a broader level, these intellectual shifts were themselves the results of many decades of work in science and math that had increasingly dislodged human beings from positions of dominance or centrality. Geology had replaced a Biblical account of creation with a geological timescale in which human beings barely figured; evolutionary thinking had broken down distinctions between human beings and other animals; astronomy had shown that the solar system was in no way central to the stellar universe, and both physics and math were moving toward theories of the physical world that upset Newtonian and Euclidean conceptions of space.
In Worms, Darwin argues against models of the world that are essentially hierarchical, such as a great chain of being or a teleological model of evolution. Darwin’s minute descriptions of earthworm activity and behavior repeatedly critique the notion that human bodies and minds are exemplary. Focusing on the “mental power” and muscular force of earthworms, he urges his reader to think about how topics ranging from sentience to agriculture look different when we begin with earthworms, rather than starting with the human as our prototype for perception, cognition, and civilization (25). Worms uses a range of literary techniques to encourage readers to reimagine the world as one in which gradations of being and cognition is the norm and the earthworm is a powerful geological force. Diverging from contemporary narratives about the significance of industrialization, Darwin instead adds his voice to an emerging ecocentric narrative.
Darwin’s meticulous observations of how earthworms explore their worlds resonate with several other Victorian challenges to a human-centered conception of space, including literary and mathematical explorations of four dimensionality. In the entry that follows, I focus on Darwin’s writing on animal cognition and earthworm perception, and conclude with his account of how profoundly earthworm digestion shapes the landscape and fertility of the earth. I also connect Darwin’s Worms to Edwin Abbott’s 1884 novella Flatland, an important work of science fiction that imagines how flat and linear geometric forms would perceive the world. These roughly contemporaneous texts set out to dismantle human perceptions that stem from possessing a highly visual brain. Both texts question the human tendency to assume that the physical world as human beings perceive it is the way the world actually is. Instead they suggest that any being’s perceptual make up determines its beliefs about what the world is like. Like Albert Einstein’s later theory of special relativity, these texts throw doubt on the belief that a single objective world exists independent of particular observers.
“Mental Powers” and Gradations of Mind: Attitudes toward Animal Cognition
For literary scholars, Darwin’s connections between human and animal minds have most often served to animalize the human: to stress the tendency of the human mind to act without conscious intention or will. Darwin inspired naturalist literary writers as diverse as Emile Zola, Theodore Dreiser, and Thomas Hardy to portray human actions as increasingly governed by instinct, drives, and chance. But in calling attention to Darwin’s own use of language, I want to underscore his investment in rethinking cultural assumptions about animal cognition as being fundamentally distinct from that of humans. The goal of Darwin’s work in Worms is neither to animalize the human nor to humanize the worm, but rather to dissolve the distinct boundaries that are often drawn between human and animal. Darwin’s work in the final decades of his life emphasizes continuities across human and non-human minds. One of the greatest obstacles Darwin faces in trying to convince his readers to take animal minds seriously is the vivacity of our own human perceptions. In Worms, he uses earthworms to persuade us to shed our senses and to imaginatively take on sensitive bodies that encounter the world not by seeing or hearing, but by sweeping those bodies across the surface of the earth.
Darwin’s speculations on worms in 1881 mark a moment of openness before fears of anthropomorphism in science led to an early twentieth-century backlash against ascribing any mental complexity to animal minds. Darwin encourages his readers to be open to enlarging their sense of what animal intelligence and experience may be like—to be open to the idea of tiny animals experiencing subjective states or even consciousness. Chapters I, II, and VII of Worms grapple with what Darwin terms the “mental powers of worms” (306). Darwin attributes “attention,” uneasiness, and even “sexual passion” to the worms (21-25, 34). Chapter II, for instance, carefully charts act of decision-making in their collection of leaves: “the worms instantly perceived as soon as they had seized a leaf in the proper manner,” he writes (73). Examining the worms grabbing leaves with their mouths in order to plug up the entrance to their burrows, Darwin notes with surprise that they try to handle the leaves in a variety of ways and seem to learn from their experience. He warns his readers not to assume that certain actions are unconscious, unwilled reflexes:
When a worm is suddenly illuminated and dashes like a rabbit into its burrow—to use the expression employed by a friend—we are at first led to look at the action as a reflex one. The irritation of the cerebral ganglia appears to cause certain muscles to contract in an inevitable manner, independently of the will or consciousness of the animal, as if it were an automaton. (23)
This passage sets up the assumptions that Darwin wants to challenge—that animals react in a machine-like manner to outward stimuli. “We are … led to look at the action as a reflex one” because we have been trained to imagine a sharp distinction between human and animal behavior, particularly when we are interpreting the behavior of a lowly worm. Darwin’s language here directly invokes René Descartes’ dismissal of animals as automata before going on to dismiss that divide as unreasonable.
He explicitly challenges the logic of ascribing human actions to intelligence while relegating similar actions in a worm to “simple reflex action” (25):
But the different effect which a light produced on different occasions, and especially the fact that a worm when in any way employed and in the intervals of such employment, whatever set of muscles and ganglia may then have been brought into play, is often regardless of light, are opposed to the view of the sudden withdrawal being a simple reflex action. With the higher animals, when close attention to some object leads to the disregard of the impressions which other objects must be producing on them, we attribute this to their attention being then absorbed; and attention implies the presence of a mind. (23-24)
Darwin suggests that since the worm reacts differently to light in different situations, ascribing their withdrawal as mere “reflex action” is insufficient. There is no reason for us to assume that the worm’s attention cannot be “absorbed” just because it is a worm; to do so would be unscientific because our interpretation would be based on a prior assumption about the capabilities of worm minds. While Darwin is elsewhere famous for ascribing much of human action to instinct or unconscious action, here he questions any kind of Cartesian divide between mechanical animals and thinking humans through careful description of the earthworm’s decision-making processes as it judges the shape of leaves and then grasps them in the most efficient way. He discusses the fact that hunters prefer to come upon their prey when their attention is occupied so as to escape the animal’s notice: “The comparison here implied between the actions of one of the higher animals and of one so low in the scale as an earth-worm, may appear far-fetched; for we thus attribute to the worm attention and some mental power, nevertheless I can see no reason to doubt the justice of the comparison” (24-25). Darwin appeals to ideals of reason and consistency in urging his readers not to assume an absolute difference between the mental capacities of lower and higher animals. Given their behavior, it is more “just” and reasonable to conclude that worms are capable of “attention and some mental power” than it is to assume that a creature so “low on the scale” cannot think.
Ten years earlier, in his 1871 Descent of Man, Darwin explicitly sets out to break down both “our natural prejudice” and our “arrogance” in believing that human mental life is fundamentally different from and superior to other forms of mind (32). The first three chapters of Descent explore evidence for “the descent of man from some lower form” and draw comparisons between “the mental powers of man and [those of] the lower animals” (9; 34) In place of analogical connections between separate and distinct species, Descent of Man proposes an actual inherited connection between the senses of animals and human perception. By the time he is writing Descent, Darwin is emphatic in arguing that continuity and gradations—of awareness, of variation—are the principles of change in the animate and inanimate natural world. It is a mistake, he insists, to conceive of any kind of absolute break between animal and human perception. His book on worms hardly mentions humans, but as scholars such as Eileen Crist, Jonathan Smith, and Adam Phillips have shown, the language that Darwin uses and the details he incorporates about the agricultural, geological, and mental powers of worms work against beliefs in the primacy of human beings.
Naturalists and physiologists had been contemplating the idea that human nervous systems were actually inherited from physiological components of the lower animals for more than a century, so the idea of mental life as characterized by gradations of intelligence was by no means new. Erasmus Darwin, Charles’s paternal grandfather, explored the evolution of life out of non-living matter in The Temple of Nature, published the year after his death in 1802. It traces the growth of planetary systems, the formation of the earth, and the “first specks of animated earth” that arose out of matter (30). It claims that even “Imperious man … / Arose from rudiments of form and sense” (37). His writings were based on the study of homology across species and the possibility that the earth was millions of years old. As Gillian Beer shows in “Darwin and the Consciousness of Others,” Charles Darwin was preoccupied for almost fifty years with the problem of moving between a creature’s external actions and assumptions of inner states, probing the line between responsiveness and awareness. George Romanes’s 1882 Animal Intelligence and his 1883 Mental Evolution in Animals incorporated many of Darwin’s observations on oysters, ants, bees, and larger animals.
In her 1999 Images of Animals: Anthropomorphism and Animal Minds, Crist carefully charts the extent to which “animal life is represented in profoundly divergent ways by different authors and schools of thought within behavioral science” (202). She contrasts the anthropomorphic language used by naturalists such as Darwin, Romanes, and Jean Henri Fabre with what she terms the “mechanomorphic” language of the classical ethologists and behaviorists (9). In attempting to establish animal behavior as a rigorous science, ethologists unintentionally adopted a technical language that “swept aside” any possibility of animal experience (203). Behavioral psychologists were more explicit about denying that animals had subjective states of mind.
As Crist compellingly argues, the term anthropomorphism, often used pejoratively, has serious limitations: “writing off ‘conscious action’ as anthropomorphism commits the deep (in my view) fallacy of anthropocentrism” (“Inner Life of Earthworms” 7-8). The word “anthropomorphism” takes human forms of consciousness as its measure of mental complexity and sophistication. Tiny creatures like worms are often invoked in such debates because of their evident dissimilarity to human beings, and they therefore make an interesting test case of shifting attitudes toward attributing inner states to non-human animals. In the 1980s, J. L. Gould and C. G. Gould suggested that “insects stand … as testaments to the power of blind behavioral programming, and as such remind us to be wary of attributing to vertebrates anything more than larger, more interesting on-board computers” (quoted in Crist, Images of Animals 85). It is this kind of pervasive anthropocentrism that Darwin subtly but forcefully attacks in his final book. He emphasizes again and again that to begin with human beings as the standard for perception, mental states, decision-making, or even agricultural labor is an act of distortion based on a retrospective view of the sequential emergence of being and sentience. Crist points out that Darwin’s “wish ‘to learn how far the worms acted consciously and how much mental power they displayed’” was “a formulation that turned out to be incongruent with most ensuing twentieth-century behavioral science” (“Inner Life” 3). Attributing “attention” and “mental power” to a worm can be seen as describing animals in human terms—to be anthropomorphizing them. But Darwin is suggesting that the greater fallacy is to assume that “attention” and “mental power” are themselves human categories. If cognition evolved first in animal lives, it is unlikely that attention and mental power would be solely possessed by human beings.
Considered from the vantage point of anthropocentric evolutionary biology, the earthworm is anything but evolutionarily advanced in its consciousness. This is a creature that lacks eyes and for which it may be a stretch to suggest that it possesses consciousness. In spite of this, however, Darwin’s careful assessment of the intelligence of worms can help us understand what was at stake in attributing states of mind and feeling at the time. What alternatives might there be to a hierarchical structure of mind in which human cognition, reason, and emotion were viewed as the apex of conscious life?
These types of speculation about animal behavior (which elude direct knowledge, but can be explored through observation and experiments) are the kinds of insights that later tend to get closed down in relation to animal minds within the context of behaviorism. As early as the 1890s we see the introduction of the scientific rule that came to be known as Morgan’s Canon: “In no case is an animal activity to be interpreted in terms of higher psychological processes, if it can be fairly interpreted in terms of processes which stand lower in the scale of psychological evolution and development” (Morgan 59). By opening up such conversations about the mental states of animals, Darwin and Romanes paradoxically inspired the subsequent scientific shift toward denying that animals could have any “higher psychological processes” at all. The irony here lies in the fact that Morgan’s Canon reiterated exactly the kind of absolute break between human and animal that Darwin saw as scientifically suspect.
Wormspace: Imagining the World through the Sense of Touch
The earthworm’s very lack of evolutionary development—its almost sole dependence on the sense of touch—becomes an advantage in enabling Darwin to stimulate his reader’s imagination, and to wrest it out of an anthropocentric assumption about what the physical world is like. Touch is a primordial sense—the one sense that cuts across every species. Recognizing that touch relies on direct contact with the world in contrast to a radiating three-dimensional vision helps attune us to unfamiliar perceptual experiences.
One of the primary accomplishments of Darwin’s Worms is that it serves as a guide to what it might be like to be a worm, given their perceptual make up, habits, and range of motion. The question of what it might be like to be another animal was raised famously by Thomas Nagel’s 1974 essay “What is it like to be a Bat?” Nagel focuses on bats because of their status as fellow mammals that remain “fundamentally alien” (438). Bats “present a range of activity and a sensory apparatus so different from ours,” Nagel writes, “that the problem I want to pose is exceptionally vivid” (438). Bats navigate and perceive the three-dimensional world by sonar or echolocation, a sense that is “not similar in its operation to any sense that we possess” (438). Nagel describes trying “to imagine … that one has very poor vision, and perceives the surrounding world by a system of reflected high-frequency sound signals” and notes that sonar is “a form of three-dimensional, forward perception” (439). Like Darwin’s book on worms, Nagel’s careful descriptions of how a bat takes in information about the world suggests how much our own perceptual make up determines what we think the world is like. But unlike Darwin, Nagel emphasizes the inadequacy of the human imagination, concluding that we cannot form more than a “schematic” conception of what it is like “for a bat to be a bat” (439). The process, he writes, is “incompletable,” and the resources of one’s own mind “are inadequate to the task” (439). Part of the fascination that surrounds this essay lies in the way Nagel first sets his reader’s imagination going and then dismisses that imagination as fundamentally ineffectual. Just as he is beginning to build up the alien form of bat perception in our minds, he declares that such perceptions are off-limits.
In his 2013 article “On Being an Octopus,” philosopher Peter Godfrey-Smith resists Nagel’s conclusions by emphasizing the potential power of both memory and imagination. With his elaborate attention to the physiology of octopuses, Godfrey-Smith suggests that imagination based on careful observation, experiment, and knowledge of an animal’s habits can be a particularly useful tool. He writes:
Getting a sense of what it feels like to be another animal—bat, octopus, or next-door neighbor—must involve the use of memory and imagination to produce what we think might be faint analogues of that other animal’s experiences. This project can be guided by knowledge of how the animal is put together and how it lives its life. (50)
Worms is packed with information about the habits of worms based on extensive experiments, as well as their sensory and nervous structure. If we evaluate Darwin’s book as a guide to what it is like to be an earthworm, we can divide the work that the book does into two different types of technique: destructive and constructive. It is destructive in that Darwin uses several strategies to break down his reader’s certainty that the ways in which human beings perceive the world describes is what the world is actually like. And it is constructive in that Darwin uses descriptions of the worms, their reactions, and behavior to build up an alternative account of their world in his reader’s imagination. As with Nagel’s choice of bats, earthworms are a particularly effective subject because their senses are so alien to ours; the only sensory overlap between human beings and earthworms is through the sense of touch.
It may be instructive to look at a purely literary example of how focusing on the sense of touch can alter perception. Early in Thomas Hardy’s 1895 novel Tess of the D’Urbervilles, Tess works tending fowls for the blind Mrs. D’Urvberville, Alec D’Urberville’s mother. Mrs. D’Urberville inspects her individual chickens through touch, and as Hardy suggests, discerns very different details about their bodies than a highly visual person might:
While the old lady had been speaking Tess and the other maid, in obedience to her gestures, had placed the fowls severally in her lap, and she had felt them over from head to tail, examining their beaks, their combs, the manes of the cocks, their wings, and their claws. Her touch enabled her to recognize them in a moment, and to discover if a single feather were crippled or draggled. She handled their crops, and knew what they had eaten, and if too little or too much; her face enacting a vivid pantomime of the criticisms passing in her mind. (70)
In this passage, Hardy uses words on a page—which have minimal sensory content of their own—to describe chickens as they are experienced through the sense of touch. By asking us to imagine that this woman inspects the chickens with her hands alone, he helps us to better attend to the chicken’s physical body—the parts of its head and the contrasting textures of beak and comb, its feathers, the food partially digested in its crop. The first step of suppressing the blind woman’s vision helps the reader imagine that hers will be an experience different from what our own would be in a similar situation. That is what I am referring to as a destructive act: unbuilding a chicken as we know it before building it up again through verbal description.
Like Hardy, Darwin encourages his readers to imaginatively deactivate their vision as they read about his experiments on worms. Among the features that Darwin added to his 1837 observations of worms were his own extensive experiments on the kinds of sensory stimuli that worms respond to, much of which took place at home with the help of his sons. His focus on the sense of touch in the earthworm upsets the everyday conception that the spatial world is fundamentally as human beings tend to perceive it: three-dimensional and perspectival. By meticulously describing the behavior and sensory apparatus of earthworms, he invites us to imagine alternate perceptions and conceptions of space.
Minutely cataloguing worms’ responses to light, heat, smells, and—more unexpectedly—piano playing in a range of contexts, Darwin explains to the reader that worms do not see or hear; they are “destitute of eyes” and possess a “feeble” sense of smell, and while they are very sensitive to vibrations moving through solid matter, such as soil, they don’t respond to undulations in the air, as humans do (19). Darwin describes even the little hearing worms do as a form of touch: they ignore notes of the piano until their pot is placed on the actual surface of the instrument, at which point worms perceive its vibrations through their bodies. Worms “are not disturbed by crawling over each other’s bodies, and they sometimes lie in contact. According to [the German naturalist W.] Hoffmeister they pass the winter either singly or rolled up with others into a ball at the bottom of their burrows” (34). The earthworm’s highly tactile experience of the world invites speculation about what it might be like to encounter only the world that is proximate to one’s body. Darwin suggests that while worms cannot see or hear in a human sense, they obtain “a general notion of the form of the object” by moving their bodies over it (28-9).
Darwin also suggests that the way an earthworm orients itself in space differs dramatically from that of human beings. As earthworms extend themselves out of their burrow into the open air, he notes, they tend to sweep the surface of the ground around the burrow while keeping their tails underground, attached by tiny hooks, in case they need to suddenly retreat:
When a worm first comes out of its burrow, it generally moves the much extended anterior extremity of its body from side to side in all directions, apparently as an organ of touch; and there is some reason to believe, as we shall see in the next chapter, that they are thus enabled to gain a general notion of the form of an object. (28-9)
This act of sweeping the earth, or moving the body over the external world to sense it, is radically unlike human orientation, which tends to involve facing forward and locating oneself in space by visual means. The senses the worm has—taste, some form of smell, and the sense of touch—all involve proximity to the rest of the world, so we can guess that the conception of space that a worm possesses corresponds to the range of space to which it has physical access. Darwin notes that worms keep their tails inserted in their burrows as they explore the areas around them, extending all but the end of their bodies out of the ground.He writes “By the expansion of this part of their bodies, and with the help of the short, slightly reflexed bristles, with which their bodies are armed, they hold so fast that they can seldom be dragged out of the ground without being torn into pieces” (14). Compared to human physiology, an earthworm’s spatial perception is less forward-focused.
Touch is a particularly interesting form of sentience not only because it is so widely distributed across species, but also because it occurs very early in evolutionary terms; touch is present even in plants to some extent. Like many of his contemporaries, Darwin uses the term sentience to indicate a baseline form of responsiveness to one’s environment that does not have to be centralized in a brain, but can simply occur in parts of an organism. Darwin’s own work on climbing plants shows that their tendrils and petioles “ascend by the aid of irritable or sensitive organs” (Climbing Plants 46) that respond to the presence of thin pieces of thread. The words “irritability” or “sensitivity” denote degrees of responsiveness: irritability merely indicates a discernible reaction to stimuli, while sensitivity can suggest an interior state behind that reaction.
In his 1855 The Senses and the Intellect, British psychologist Alexander Bain stresses that not only is touch the most widely distributed sense—“never absent in any species”—but also that it is the most generalized sense within individual organisms (159). Bain is writing several years before Origin of Species was published, but after many thinkers, including Jean-Baptiste Lamarck, Eramus Darwin, and Robert Chambers, had been working with ideas of what we now call evolution. Bain cites the physiologists Robert Bentley Todd and William Bowman, who suggest that touch comes closest of all the senses to what they term “common sensation,” the “sensibility diffused over all the internal organs and tissues,” the body’s (often vague) sense of itself, as a general form of awareness of that cannot be easily localized within an organism. Touch has “its seat in the skin, and in certain mucous membranes, as that of the mouth,” yet it is still more far widely distributed across the body than taste, hearing, vision, or smell (159). Indeed, it is impossible to draw a sharp line between where common sensation leaves off and touch begins:
[Touch] is the simplest and most rudimentary of all the special senses, and may be considered as an exalted form of common sensation, from which it rises, by imperceptible gradations, to its state of highest development in some particular parts. It has its seat in the whole of the skin … and is therefore the most generally diffused over the body (159).
The localized sense of touch, then, is an intermediate step between the diffuse common sensation and more specialized senses such as hearing or sight in the evolution of perception. Writing about the human senses, Bain characterizes touch as the sense human beings use to “embrace the outer world” (160). He notes: “The notions of the size, shape, direction, distances, and situation of external bodies may be acquired through touch, but not by either taste or smell” (160). Bain suggests that we think of touch “as a compound of sense and motion.” Its mode of action is mechanical—contact or pressure—but the conceptions that arise from touch are complex. He writes, “it is to the muscular part of the sense, or to the movements of the touching organs, that these conceptions [of size, shape, direction, distance, and situation] owe their origin and embodiment” (160).
The idea that concepts of shape, size, and space depend on the sense of touch is crucial with respect to earthworms. Given their perceptual make up, Darwin suggests that most of worms’ conception of space must involve direct contact with external objects and surfaces that they move across or through. Earthworms travel underneath the earth, in the burrows that they dig, and also across the surface of the earth, on top of the soil. Darwin’s experiments and observations about worm senses enable one to picture wormspace as extending along a relatively flat surface—of the earth—but reaching neither high into the air, nor far below the surface of the earth. From Darwin’s description, the worm’s world appears to be planar, lacking much sense of how things are arranged in three-dimensional space. Darwin offers an imaginative alternative to three-dimensional conceptions of space by conjuring up the spatial world that the earthworms must be aware of.
Earthworms’ experience of space, he suggests, must differ drastically from that of human beings in terms of senses and dimensionality. The spaces they might encounter tend to be up close and extremely proximate to the animal—unlike what the faculty of seeing at a range of distances can produce. Seeing gives human beings more of a sense of knowing the world as an abstraction than as a proximate thing. Should the range of movement of the worm seem hopelessly restricted, it might be worth repeating a point that the Time Traveller makes in H. G. Wells’s 1895 Time Machine. The Medical Man asks, “if Time is really a fourth dimension of space … why can we not move in Time as we move about in the other dimensions of Space?” The Time Traveller replies, “Are you so sure we can move freely in space? Right and left we can go, backward and forward freely enough, and men have always done so. But how about up and down? Gravitation limits us there” (7). Wells gets us to pull away from the surface of the earth just enough to begin to see our own motion as restricted to a flat—yet curved—surface. Wells hints here at the human tendency to overestimate our own abilities. Human beings radically differ from worms not in their range of motion, but in their sensory perception of space that they cannot move through, especially that acquired through perspectival vision. Darwin notes, for instance, that worms do not seem to have a sophisticated sense of how to find their way back home, an ability that is remarkable in both ants and bees. This observation does not emphasize the lowliness of the worm in relation to human beings, but the remarkable differences across species of all kinds in both how they sense the outside world and how they navigate it.
Arising imperceptibly out of more basic sensations, localized areas of touch provide nineteenth-century naturalists with an analogy for the emergence of life out of non-living matter. There is a structural similarity between the shift from common sensation to touch and what Darwin argues must be a gradual shift between not feeling and feeling. His studies of the sensitive petioles of some climbing plants—which lose their sensitivity once they find a place to attach to—may be a helpful parallel here. When we begin to think about sensation as something that manifests itself more strongly in some forms of matter than others (on the tip of a finger as opposed to a bone, for instance), consciousness looks less like something that some creatures possess and others simply do not, and more like a form of sensitivity that is unevenly distributed across individual bodies and matter. That uneven distribution of sensitivity characterizes most individual bodies. Bain discusses the fact that the epidermis is itself insensible, but the true skin beneath is extremely alive to feeling. Touch, Bain explains, involves contact, warmth, cold, resistance, and distinctiveness of locality. Its central action is “simple pressure” (166), but when paired with movement and muscular sensibility, it can give rise to “the knowledge of size, shape, direction, distances, and situation of other bodies” (160).
Imagining the way that worms might sense space tells us about how the human conception of the world is defined by our sensory organs. As creatures whose “whole body is sensitive to contact,” worms “gain a general notion of the form of an object” by moving their bodies over that object (28-9). How might objects appear different from moving a body over them as opposed to locating them visually in perspectival space? Without vision or hearing, how far into space—up, down, over and across—does the worms’ perception of space extend?
Again the work Darwin asks of the reader is both destructive and constructive: destructive in that he is asking us to suppress both vision and hearing in order to consider alternative ways of apprehending the outside world, and constructive in that through close and repeated observation of the senses and behavior of worms as they process and rearrange earth, Darwin invites us to speculate on how the world might appear different to those who encounter the world largely through touch.
Imagining Four Dimensions: Darwin’s Worms and Flatland
Darwin’s investigations of earthworm perception have some interesting overlaps with other imaginings of space in mathematics and literature at the time. Edwin Abbott’s novella Flatland appears just three years after Worms is published, and directly takes on the difficulty of imagining four-dimensional space. Vision becomes a particular impediment to imagining alternatives to three-dimensional space because it often presents itself as giving a complete picture of the world. As John Berger has written, “Perspective makes the single eye the centre of the visible world. Everything converges on to the eye as to the vanishing point of infinity” (16). Touch, by contrast—feeling one’s way through the world via what one is able to come into contact with—can produce a far less complete sense of where the world itself leaves off. In fictional texts, creating the feeling that space has or does not have edges either closes down or opens out the spaces that readers are able to imagine.
As we saw above with Hardy’s chickens being felt by the blind Mrs. D’Urberville, finding a way to deactivate vision and intensify the imagined sense of touch is a particularly fruitful technique for getting readers to imagine varied configurations of bodies and space. Darwin’s technique for deactivating vision is to meticulously describe the behavior of worms that investigate the world without being able to see, “by touching [objects] with the anterior extremity of their bodies, which serves as a tactile organ.” He reminds his readers “how perfect the sense of touch becomes in a man when born blind and deaf, as are worms” (97). While Darwin’s goal in focusing on touch is not to ask human beings to reimagine space, his writing does ask his readers to be more epistemologically humble, to consider that the temporal and physical scales at which human beings operate give us limited perception of the external world and its workings.
In Flatland: A Romance in Many Dimensions, Abbott uses contrasting access to, and assumptions about, space to highlight the fallacy of believing that space does not exist beyond the range of one’s senses. Abbott shows the power of such an illusion by vastly restricting the visual range of his imaginary characters and showing how their senses affect their beliefs about the external world. In Flatland, we find early discussions of multi-dimensional space conceived in terms of imaginary beings—Flatlanders, Linelanders, and Pointlanders—who lack sensory and bodily access to a third, second, or even a first dimension, respectively. They are physically trapped in a plane, a line, or even a point. When these beings can no longer perceive something, they believe that that thing does not exist, and construct a story about what the world is like based on the space to which they have access.
Abbott’s larger purpose is to encourage readers to begin to imagine that four-dimensional space might exist—and that what appears visibly to be the structure and limit of space, as human beings know it, might simply be an impoverished view of the dimensions that exist beyond the realm of three-dimensional human perception. Flatland focuses on a world of only two dimensions in which the entire world exists on a plane, and vision is restricted to lines and points. This two-dimensional realm is juxtaposed with several other worlds that the narrator from Flatland encounters, each with its own configuration: Pointland, Lineland, and three-dimensional Spaceland. The distinctions between these realms involve first the ways that each land’s inhabitants conceive of their respective bodies as extending in space, and second how each type of inhabitant’s perception extends into space. For example, all beings in Flatland are two-dimensional shapes: triangles, squares, pentagons, or circles. They can move freely in all directions along the space of a plane—north, south, east, and west—but neither up nor down. Visually, each individual—whatever his or her shape—appears to the others simply as a line of a certain length. They can never see one another’s fully two-dimensional bodies. Only by the sense of touch, which they term the act of “feeling,” can one being apprehend another’s “angle,” and from that conclude that the being they are encountering is a triangle (if the angle is 60 degrees), square (if it is 90 degrees), or a pentagon (82 degrees).
Flatland shows the power of the illusion that where vision leaves off, space actually ends by taking its reader into several kinds of worlds, each of which contains its own spatial and perceptual limitations. The whole “horizon” of the habitants of Lineland, for instance, is “limited to a point” (177). Lineland consists only of a line; the one-dimensional beings of various lengths can, by hearing, perceive distances along the entirety of the long line that they inhabit, but visually no one sees anything but the points that make up the ends of the two beings next to one. They can move back and forth, but can neither see outside of the line that makes up their world, nor conceive of any space existing beyond it. When the Square visiting from Flatland moves into the linear world of Lineland, then, he becomes audible to Lineland’s inhabitants, but as soon as he moves out of the range of that individual line, the king of Lineland perceives him to have completely vanished from space:
this poor ignorant Monarch … was persuaded that the Straight Line which he called his Kingdom, and in which he passed his existence, constituted the whole of the world, and indeed the whole of Space. Not being able either to move or to see, save in his Straight Line, he had no conception of anything out of it. (116)
Each type of being is convinced that where his or her perception ends, what they call “the whole of the world” ends, and the human reader is invited to make a similar speculation that spaces might exist outside of his or her own sensory purview.
Abbott’s novella suggests that what appears visibly to be the structure and limit of space, as human beings know it, might itself be an impoverished view of the dimensions that exist beyond the realm of human perception. At first, Abbott flatters human readers by contrasting the superiority of three-dimensional human vision with the restricted vision of the Flatlanders who perceives the world as two-dimensional. We are told that the narrator is a square, and envision a square from a human perspective, as if we were looking down on a flat piece of paper. We are continually asked to compare how the square sees his world (in which he cannot get outside of his own plane of existence) with how we picture his flat world to ourselves. In visualizing the square’s planar world, we are conscious of our own greater knowledge as humans and marvel at the limits of the world depicted. The fact that Flatlanders are certain that no space exists outside of their plane allows us as humans to feel superior and “in the know.”
But Abbott ultimately uses that feeling of superiority to upset our own certainty that what is outside of our visual experience simply does not exist. As we are three-dimensional creatures, he suggests, it makes sense that we perceive nothing outside that framework—but that by no means indicates that four, five, or six dimensions do not exist. Flatland ends up creating an analogy, rather than a contrast, between human beings and the Flatlanders by suggesting that our own conviction that the world is three-dimensional is probably just as blinkered a view of Space as those of the Square and his comrades.
In Fact and Feeling, Jonathan Smith places the writing of Flatland in the context of a larger Victorian preoccupation with “debating the nature of space and our knowledge of it,” particularly in Non-Euclidean geometry (181). He cites a review in Nature that links Flatland to “speculations” by the mathematician J. J. Sylvester in an 1869 address about “the existence of a book-worm ‘cabin’d, cribb’d, confin’d’ within the narrow limits of an ordinary sheet of paper” (181). “For Sylvester,” Smith writes, “… three-dimensional Euclidean geometry is not the science of space in general, but the science of the space of our experience” (181-82). Sylvester, we might guess, chooses to conceive of “infinitely attenuated book-worms” both because of their tininess and their inability to see; his invocation of bookworms sets up a contrast between the worms’ perception of their surroundings from within and a human being’s external view of “an infinitely thin piece of paper” (181). In visualizing the paper, the human reader imagines seeing in more dimensions than the bookworm perceives.
Abbott’s Flatlanders and the non-visual experiences of Darwin’s earthworms encourage us to imagine physical limitation coupled with free movement in a certain dimension. We find a similar image in Alan Lightman’s 1993 novel Einstein’s Dreams, also in the service of invoking multi-dimensional space. An ant crawling around a chandelier believes itself to be walking along a straight line when its path in fact inscribes a circle. Whether it is due to the flatness of the paper (as with Sylvester’s bookworm) or the scale of the perceiver (as with the ant) perception becomes a form of limitation that prevents one from perceiving the shape of one’s environment as it would appear from a different position, scale, or form of perception. Abbott, Sylvester, and Lightman each suggest that this is what vision does for human beings: it prevents us from seeing or believing in dimensions outside our ordinary three. We begin to get a sense of the fact that writers are always closing down the edges of the spaces that we as readers have access to, and then suddenly making new spaces imaginatively available. Fictional spaces can become newly accessible in a range of ways: when a writer opens up a portal of some sort (as happens in Through the Looking Glass or The Lion, the Witch, and the Wardrobe, or when a character becomes aware of a previously unperceived space (Charlotte Bronte’s attic prison, Frances Hodgson Burnett’s secret garden, or Abbott’s three-dimensional world).
While they are very different types of books, both Flatland and Worms play on the reader’s powers of imagination to upset conventional notions of space. Flatland explicitly creates a thought experiment to inspire alternative conceptions of space. We can understand some of Darwin’s experiments as performing a similar stimulus to the imagination—cataloguing the reactions and non-reactions of earthworms who are living in a different perceptual world. “They took not the least notice of the shrill notes from a metal whistle, which was repeatedly sounded near them,” Darwin writes, “nor did they of the deepest and loudest tones of a bassoon” (27). He conjures up a human world that is spatially continuous with that of the worms, but perceptually discontinuous from it. Loud sonorous music fills a room but makes no impact on the earthworms. Similarly, the worms “were indifferent to shouts, if care was taken that the breath did not strike them” (27). He elaborates on these experiments—playing a piano “as loudly as possible” or making the ground tremble by having beaten it with a spade”—not to show that worms lack perception, but that the form their perception takes is radically different from ours (27-8). Darwin does not explicitly offer his readers a thought experiment (like those of Abbott or Wells) or any truth claim about what the actual perceptions of worms are like. Yet his minute attention to the worm’s sensory physiology combined with extensive observations of how worms explore and respond to different aspects of their environment build up a version of the world that bears little resemblance to the one with which human beings are familiar.
The Powers of Digestion
Much as Darwin’s account of touch asks us to rethink our own perception of, and orientation in, space, his focus on digestion is crucial to the anti-anthropocentrism of the book in the way it asks us to rethink concepts of will and motivation. Digestion, taking things into the body and expelling waste out of it, not only upsets ordinary notions of where the boundaries between self and world lie, but also forms the very basis of being. Darwin describes digestion not only as an act performed by individual worms, but also as a local agricultural force, and even as a large-scale temporal and spatial-geological one. Darwin links the agricultural and geological actions of worms both to ploughing and to the production of the chalk of England “by the digestive action of marine animals” (“On the Formation of Mould” 577). This is one more way in which Darwin’s work moves his readers away from assuming that individual human agency is the primary force in earthly change. He stresses instead the interdependence of material beings on their surroundings and on one another.
Digestion focuses on the activity (apart from reproduction) that most upsets a notion of individual beings as autonomous and whole. Darwin’s Worms offers a model of the world that involves finite amounts of matter—a closed system—and yet is by no means made up of stable entities. On the one hand, worms are sentient in ways we don’t recognize; and on the other, their collective action, which takes place without planning of the kind we recognize, is crucial to the earth’s vitality. So not only is their sentience of a different order than ours, but their labor is also more productive. In his early paper on the formation of mold, for example, Darwin is already remarking that
the agriculturist in ploughing the ground follows a method strictly natural; and he only imitates in a rude manner, without being able either to bury the pebbles or to sift the fine from the coarse soil, the work which nature is daily performing by the agency of the earth-worm. (“On the Formation of Mould” 577, qtd. in Phillips 50)
In place of nineteenth-century models of history as progressing from primitive hunting and gathering, to settled agriculture, and finally to centralized nation states and industry, Darwin here views the natural “agency” of worms as more refined than the tool-wielding human farmer. In his 1881 book he continues to use the vocabulary of labor, architecture, and farming technology to destabilize the idea that mankind is the culmination of earthly activity. Human beings are instead portrayed as “rude” arrivistes attempting to emulate the work of the worm on a smaller scale, restricted to the surface of the earth.
Darwin’s 1881 book adds to his 1837 paper years of his own observations of the “action” and “habits” of worms, including detailed measurements showing that “[i]n many parts of England a weight of more than ten tons of dry earth worms annually passes through their bodies and is brought to the surface on each acre of land” (Worms 305). Darwin is interested in momentous yet imperceptible forces that elude human notice either because of their vastness, their tininess, or both. In this case, the central force is digestion, which Darwin portrays as not only an act of feeding an individual organism, but also as a significant agricultural and even geological power. In digesting the earth, the worms become, as Adam Phillips puts it, “gratuitously benign conservers of the earth” (31). This book shows a remarkable attention to small causes and giant effects, as Darwin urges his reader to envision “a wide, turf-covered expanse” and reflect “that the whole of the superficial mould over any such expanse has passed, and will again pass, every few years through the bodies of worms” (313). Darwin emphasizes the significance of this large-scale action by focusing on accreting effects. This he does both numerically and visually, by charting the movement of ruins or the rocks of Stonehenge that are gradually buried—and therefore preserved—over time. By linking tiny creatures to the largest movements of the earth, the history of the world to the agency of worms, and the earth’s surface to wormy interiors, Worms quietly celebrates the results of invisible, subterranean action.
The world that Darwin invokes is a materialist one in which everything is in a constant process of becoming something else. Earth moves through the worms as the worms move through the earth. In Worms, consumption and digestion—rather than procreation or the movement of wind and water—are the central forces that fuel such change. Darwin’s account of the worms echoes Biblical and earlier literary invocations of dust unto dust, and yet his version of a materialist world driven by consumption highlights earthworms as agents of change, and the nutritive drive as a motivating force.
Darwin’s emphasis on the action of digestion confuses distinctions between inside and outside and between the animal and vegetal. Recent work on new materialism pursues a similar goal. In Vibrant Matter, which includes a chapter on Darwin’s Worms, for instance, Jane Bennett suggests that emphasizing the “vitality of matter” is itself a way of combatting anthropocentricism: “my hunch is that the image of dead or thoroughly instrumentalized matter feeds human hubris and our earth-destroying fantasies of conquest and consumption” (ix). Darwin portrays digestion as an action that turns one substance into another, both inside and outside of the worms’ bodies. The bodies of Darwin’s earthworms have two important surfaces—a sentient outer one and their less sentient intestinal canal, which is capable of tolerating pebbles and roughage. Unlike the outer skin, this internal surface physically absorbs and transforms the world that moves through it. Within the individual, the worm’s most important work indeed occurs in the intestinal canal, which has deep involutions, creating what Darwin describes as “an extensive absorbent surface” (36). But even this work cannot be said to begin inside the worm. Earthworms moisten leaves with a fluid that they secrete before consuming them, with “the result … that they are partially digested before they are taken into the alimentary canal,” a detail that, again, complicates where the important work of worms is performed (43). Jonathan Smith insightfully links Darwin’s interest in worms—in particular his illustration of enlarged worm excrement—to a Bahktinian version of the grotesque, which “ignores the closed, smooth, and impenetrable surfaces of the body and retains only its excrescences and orifices” (250; see also Figure 4). That insight could be extended to the earth that Darwin describes as “animal mould”—while the earth resists human entry beneath its surface it is anything but closed, smooth, or impenetrable to the worms.
Finally, Darwin’s celebration of digestion places it at the center of what it means to act. In “When Zoophytes Speak,” Danielle Coriale demonstrates the ways in which naturalists imagined “coral polyp productivity” in the 1860s “as a form of collaborative labour” that raised “tiny buildings” and contributed to “civic life” (28-9). By highlighting the importance of worms “in the history of the world” and particularly in the agricultural landscape of England, Darwin similarly places worms (rather than landowners or human laborers) at the center of civilization (305). As worms fuel the process of turning dust into dust, they make life possible. Darwin compares worms to highly skilled gardeners or architects who process and rearrange matter so as to enable plants to grow, and decaying bodies to turn back into plants:
They mingle the whole intimately together, like a gardener who prepares fine soil for his choicest plants. In this state it is well fitted to retain moisture and to absorb all soluble substances, as well as for the process of nitrification. The bones of dead animals, the harder parts of insects, the shells of land-molluscs, leaves, twigs, &c., are before long all buried beneath the accumulated castings of worms, and are thus brought in a more or less decayed state within reach of the roots of plants. (309-10)
Darwin suggests that no creature mixes its labor with the soil more effectively and even skillfully than the worm, which is endowed with a prodigious appetite and “powerful transverse muscles” that transform the outside world (18).
Darwin’s talent for apprehending the impact of invisible accumulated forces has been remarked upon often. Henry Wace’s review of Worms in The Quarterly Review observes that all of Darwin’s late works illustrate “the incessant and infinite interaction of the various parts of nature upon each other, and the manner in which the most conspicuous and most comprehensive results are produced by the gradual accumulation of the slightest influences” (182). More recently, Adam Phillips compares Darwin to Sigmund Freud in “always regard[ing] what he can see—in this case, the literally superficial layer of earth—as the result of a hidden process” (47). In On the Origin of Species, Darwin himself reflects, “we are always slow in admitting any great change of which we do not see the intermediate steps … [T]he mind … cannot add up and perceive the full effects of many slight variations accumulated during an almost infinite number of generations” (482). In his 1868 lecture “On a Piece of Chalk,” T. H. Huxley similarly links the tiny actions of mollusks, that “minute architect below” the surface of the sea, to vast geological formations (198-9). As Jonathan Smith puts it, “skepticism about the stupendous cumulative effects of the lowly earthworm was the same prejudice against which Lyellian geology and natural selection had struggled” (269). Human resistance to the importance of worms is itself a sign of our intellectual limitations, and our tendency to impose teleological and anthropocentric narratives onto the world or discount forces which we don’t have direct perceptual access to.
The overall structure of Worms moves from interior being to exterior world. In the process, Darwin deliberately confuses distinctions between animal and vegetable and inside and out, constantly picturing worms moving through the earth as earth moves through the worms. As animals that do their labor continuously and without intention—and yet produce life—worms upset notions of how change over time occurs. Foregrounding worms, Darwin places digestion rather than reason or morality at the center of what it means to act. Even the prepositions that structure the title of Darwin’s final book, The Formation of Vegetable Mould, through the Action of Worms, with Observations on their Habits, emphasize relation and modification rather than autonomy and progress.
When we contemplate the world as it is encountered by beings radically different from ourselves, our anthropocentric assumptions break down and the imagination opens up. In pushing back against Nagel’s claim that our imagination is inadequate to the task of imagining other minds, Godfrey-Smith proposes that in order to “produce what we think might be faint analogues of that other animal’s experiences,” our imagination can “be guided by knowledge of how the animal is put together and how it lives its life” (50). I have suggested that we read Worms as such a guide, and consider the work both Darwin and Abbott do on their reader’s imaginations as simultaneously destructive and constructive. Both authors work to undo human certainty about the superiority of our perceptions by helping us imaginatively to construct the perceptions of beings whose bodies and perceptual organs are radically different from ours.
I want to conclude by pointing out two specific literary techniques Darwin uses in Worms to stimulate his readers’ imaginations and open their minds to continuity across living beings. First, one of his most powerful strategies is that of suspending or dismantling his reader’s imaginative use of vision. He does so not only by explaining that worms “are destitute of eyes,” but also by copious descriptions of situations in which worms laboriously examine a leaf or a pine needle via the sense of touch. In testing their sensitivity to light, Darwin notes moments in which, in response to the sudden appearance of “a bright paraffin lamp,” “they often “raised the anterior tapering ends of their bodies from the ground … or they moved their bodies from side to side as if feeling for some object” (21). This language asks us to imagine what the eyeless worm’s experience of space might be like by getting us to picture a body extending itself in space and sensing through touch what we as human beings conceive of as a primarily visual stimulus: a sudden bright light. Encouraging a reader to imagine not being able to see is a crucial element in many of the studies of alternative ways of perceiving I have discussed—including Tess of the D’Urbervilles, Flatland, Einstein’s Dreams, and Nagel’s “What is it Like to Be a Bat?” Whether it involves invoking human blindness, two-dimensional beings, or bat perception, the simple act of getting a reader to consider a non-visual account of the world has a profound epistemological effect.
Second, Darwin’s descriptions of experiments often create a marked contrast between the world as he and his sons perceive it and the reactions or non-reactions of the worms. The most dramatic of these are his invocations of shouts, whistles, pianos, and bassoons which are met with indifference and “quiet” (26). Here, again, it is helpful to link these scenes to contrasts set up by other writers: Tess watching the blind Mrs. D’Urberville feel her chickens’ beaks, combs, cocks, wings, and claws while Mrs. Durberville’s “face enact[s] a vivid pantomime of the criticisms passing in her mind”; Flatland’s narrator picturing the king of Lineland’s perception of his one-dimensional kingdom; or Nagel encountering an “excited bat” within a confined space. These scenes each set one mode of perception next to another in order to juxtapose two very different ways of experience a single set of stimuli: seeing the chickens versus examining them through touch; seeing a three-dimensional world, or experiencing the world from the perspective of one dot in a line; or sensing a room and other creatures through sight and hearing rather than through sonar perception.
One of Darwin’s most important contributions is to set his accounts of the worm’s bodily structure (“how the animal is put together”) next to elaborate descriptions of their responses to the experiments he designed (“how it lives its life”). In “Darwin and the Consciousness of Others,” Beer notes that “direct intimacy” with phenomena directly observed “ground[s] empiricism” for Darwin; from the “mid-sixties on … Darwin dwells with examples as the essential fuel for thought” (252, 254). Emphasizing his interest in “the mental and emotional capacities of the whole range of organic beings,” she cites his belief that imaginative speculation and the suspension of skepticism are both crucial to science and one of the strengths, in fact, of human thinking (244). Rigid skepticism about animal consciousness—and science in general—has been, as Darwin puts it, “injurious to the progress of science” because while skepticism is helpful in interpreting data, it has a tendency to prevent people from contemplating whole areas of inquiry (quoted. in Beer 245). And in fact that was exactly what happened not long after Darwin’s death in 1881. In western scientific institutions, speculation about animal minds was actively discouraged until the 1970s, when cognitive ethnologists such as Donald Griffin again began to challenge the prevailing model of animals as automata. Over the past twenty years a growing fascination with the mental capacities of both vertebrates and invertebrates has led many scholars back to the work of Darwin. This is in part, I would suggest, because of the techniques he uses to open up the imagination and break down anthropocentric assumptions. What the experiences of other creatures are like is not something that we can ever know for certain. It is, however, a problem that an interest in the evolution of sentience and careful study of alien beings encourages us to imagine.
Note: I am grateful to Ivan Kreilkamp, Mark Laidre, and K. K. Collins for their reading suggestions, and to Deb Gettelman, Maia McAleavey, Laura Saltz, Steve Biel, Hillary Chute, Reed Gochberg, Emily Gowen, Meegan Kennedy, Daniel Williams, Cherrie Kwok, Paul S. White, and another anonymous reader for their comments on drafts of this essay.
published July 2017
HOW TO CITE THIS BRANCH ENTRY (MLA format)
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RELATED BRANCH ARTICLES
 Compare Danielle Coriale’s rich account of how the “cumulative effects of minute causes” function in regard to coral polyps (20). The power of polyps as collective beings stimulated the imagination of many Victorian naturalists. Coriale’s article focuses on how scientific fantasies about polyps put pressure on ideals of autonomous individuality. She studies argues that tiny polyps were a life form that resisted, repulsed, or confused sympathetic attachment, human identification, and intelligibility in the Victorian imagination,” implying that it was their dissimilarity from human beings that gave polyps such imaginative force in narratives about politics, consumption, and architecture (19).
 See Smith Charles Darwin and Visual Culture 257-8; Browne 365-7.
 See Phillips on Darwin’s career-long critiques of the “arrogance” of “Man” in his journals, in Origin, as well as in Worms (40). Phillips writes that “Darwin was describing a war in which there was no ‘great work’ or ‘exalting object’ …This was the bad news Darwin brought to a political ethos committed to progress and political expansion” (40).
 In “The Mental Life of Plants, Among Others,” Sacks turns back to his early interest in Darwin’s Worms and the works of George Romanes to discuss continuities across animals and plants in what we might call mental activity. He discusses the 1880s as a moment of open speculation about non-human cognition before the constraints of behaviorism. The article compares how animals and plants are currently thought to signal from cell to cell, and notes Darwin’s insistence plants and animals “were closer than one might think” (6).
 See especially the 2009 addition to Darwin’s Plots, “Darwin and the Consciousness of Others” 242-55.
 Crist’s analysis of several specific techniques Darwin uses in Worms to portray what she calls the “inner life of earthworms” as something that involves experience, cognition, a subjective viewpoint, and conscious action 2002, 3-8. Situating Worms in a long history of scientific attitudes toward and ideologies about animal minds, she argues that “his study brilliantly shows that the question of ‘conscious action’ in animals is not inherently problematic because it is not rational to presume, prior to inquiry, that the existence of conscious action is unlikely, even among invertebrates” (7). “Writing off ‘conscious action, as anthropomorphism,” she continues, “commits the deeper (in my view) fallacy of anthropocentrism” (7-8).
 See Crist “The Inner Life of Earthworms” (210-23) and Friend (40-4) on the influence of Descartes’s writings on animal behavior at different historical moments.
 See White’s fascinating discussion of the inconsistency with which Victorians viewed different species as either like human beings or like machines: “In laboratories of the new reflex physiology, frogs became indistinguishable from machines” whereas dogs could be viewed as “tender” and “joyous” (61, 68). Darwin’s engagement with the question of what actions should be termed reflex actions and what actions are conscious is far more complicated than I am suggesting here. Part of the problem may be that the distinction between reflex and conscious is a false binary. But another important complication is that conscious action in both human beings and animals can be converted into reflex action through repetition and habituation. Darwin was interested in how animals developed new reflex actions in order to survive changing conditions.
 See White on the complexity of reflex and mind.
 In “The Inner Life of Earthworms,” Crist writes that Darwin’s writing on worms asks human beings “ultimately, to imagine ourselves, to describe ourselves, from nature’s point of view; but in the full knowledge that nature, by … definition, doesn’t have one” (135).
 “Darwin and the Consciousness of Others” is a new chapter added to the 2009 edition of Darwin’s Plots. See Beer (242-3) and Levine Realism, Ethics, and Secularism (154-61).
 See Crist Images of Animals, Friend (33-61), and Sacks (4-5).
 For the idea that touch occurs across all animals see Aristotle De Anima (162) and in the nineteenth century, Bain Senses and the Intellect (159).
 This at least describes my experience of Nagel’s essay. It inspires access to alternative forms of perception and then explicitly denies that access. For me the parts that remain most vivid are his descriptions of bat bodies and the way bats take in information about the world, descriptions that resemble Darwin’s accounts of worms in their attention to the bat’s perceptual make up, the body’s experience of and access to space, bat behavior, and a even a brief scene of a human being spending “time in an enclosed space with an excited bat” (438). Compare George Levine’s claim that “literature at least tries to defy Nagel’s argument” (Realism, 248).
 Chapters I and II (8-128) detail the kinds of sensory stimuli that worms respond to.
 In “Inner Life of Earthworms,” Crist notes that “For Darwin, the earthworms’ ability to judge shape was the most significant indication of intelligence” (4).
 Like other contemporary caricatures of Darwin, this cartoon includes images of apes and monkeys. The visual similarities between the monkey’s tail and the earthworm lampoon the suggested evolutionary relationship. “Man is But a Worm,” Punch. 6 December 1881.
 Many explorations of four dimensions followed the 1855 biography of Carl Freiderich Gauss. In her Broadview edition, Lila Marz Harper places the novella in the context of Hermann von Helmholtz’s 1870 review essay of geometry textbooks that deal with non-Euclidean space and C. H. Hinton’s 1880 article “What is the Fourth Dimension?” (Harper 192-3; 194-198).
 In a fascinating section on the aesthetics and decision-making of Darwin’s worms, Caroline Arscott relates an experiment that Darwin did with worms in which he “introduce[ed] leaflike pieces of paper into the worm’s environment,” having cut the writing paper into “narrow-based and very narrow-based triangles,” in order to see how a worm “assesses their shape” in order to select “the sharp apex to grab” (254). This interest of Darwin in how non-visual creatures perceive paper and human-made geometrical shapes links his writing even more closely to the interests of both Abbott and Sylvester.
 See Crist “Inner Life of Earthworms” (3-8) on Darwin’s architectural language in Worms and compare Coriale’s discussion of coral polyps (28-9).
 See Phillips (50).
 See Smith Charles Darwin and Victorian Visual Culture (244).
 See Smith Charles Darwin and Victorian Visual Culture, Phillips (46-63) and Coriale (31-2) on the “minute agencies” of polyps. Ulin emphasizes that for Darwin, the labor of worms is not only agricultural work but cultural: “They carry on a full complement of cultural activities, largely through the agency of their excrement” (304-5). Crist focuses on how Darwin’s language of architecture and home “accent[s] the skill and life of worms” and presents worms as “inhabitants of spaces that possessed features engineered for utility, comfort, and security” (5-6). Smith focuses on the illustrations in Worms, and links Darwin’s commitment to “blending of forms … and the blurring [of] boundaries” to grotesque realism (249).
 See also Smith 2006 on Darwin’s illustrations of worm shit as an agent of “preservation,” pictured as “tower-like” or volcanic forms (251-3).
 Bahktin quoted in Smith Charles Darwin and Victorian Visual Culture (250).
 See, for instance, Beer (36-38) and (246), and Levine Darwin the Writer (126).
 See Crist, Images of Animals, for more on Donald Griffin’s contributions to studying animal minds.