The second book of Ranulf Higden’s Polychronicon opens by considering the problem of “þe ordre of þe story.” To illustrate the principle of good structure, namely, that lesser things should serve the greater, Higden crafts a bio-eco-rhetorical analogy. For the human body as for the world itself, everything functions well if all is proportional, arranged well, and directed at its proper ends. Otherwise, “anon is grete distourbaunce i-made”: earthquakes and thunder in the macrocosmos; in the human microcosmos, “ache, sicknesse, and sorwe”; and, presumably, although this is unexpressed, in Higden’s massive historical compendium, disarrangement. What his discussion requires is a base, a fundamental ordering principle to fix a distinction of lesser from greater and to hold each of these poles in place.
Naturally enough, Higden finds this sure foundation in oysters:
Also as it is in þe parties of þe grete world þat þey beeþ so i-ordeyned and i-sette þat þe ouermese of þe neþer kynde touche þe neþermeste of þe ouer kynde, as oistres and schelle fishe, þat beeþ as it were lowest in bestene kynde, passeþ but litel þe perfeccioun of lyf of treen and of herbes, for þey mowe not meue hem but as culpes of þe see waggeþ wiþ þe water, elles þey cleueþ to þe erthe and mowe noþer see ne hire, ne taste, ne smelle, but onliche fele when þey beeþ i-touched.
The parts of the great world are so ordered and set that the highest point of the lower kind touches the lowest part of the kind above it, as oysters and shell fish do, that are, as it were, the lowest in animal kind, barely surpassing the perfection of the life of trees and of herbs [that is, they barely surpass the highest form of plant life], for oysters might not move themselves except in the way that kelp of the sea wags with the water, as otherwise they cling to the earth and cannot see nor hear nor taste nor smell; but they feel only when they are touched.
Higden gets his scaffolds from two sources: first, Aristotle’s tripartite, accretive division of the soul into the vegetable (which provides for nutrition, growth, and life itself); the animal (sense, motion, and reaction); and the intellective (everything belonging to the “nonfinite” list of capacities thought to travel uniquely under the banner of human reason); and then the scale of being, a taxonomy that elaborates on this tripartite model by sequencing everything from the highest, spiritual beings to the lowest, soulless forms of existence. Though this model would hypothetically allow some fortunate animal species to be closest to intellective existence, in practice, no animal ever held this position consistently: dogs had it sometimes, for their loyalty; bears, because they mate as we are supposed to do, face to face; and pygmies, because of their shape—although even they could be barred from humanity, because legends about them held that they were heliotropes, like sunflowers, mechanistically moved by a sun they only appeared to worship. But here, neither the upper limit nor any other rates Higden’s attention. He provides no other border creature: neither between plants and stones, nor animals and humans, nor humans and spiritual beings. He needs just the one line, and everything else neatly follows. Just before the oyster, Higden enumerates the proper mathematical proportions of a well-arranged human body; just after, the gradual senectitude of the world since its creation, repeated on a smaller scale with every human life as it declines towards its own death. Then he lists a vast array of human customs throughout the world. First stability, then the oyster, then a bit of human difference, but not so much that the human becomes unrecognizable as human, as if the oyster’s stolid reliability laid the foundation for a safe field of play.
To be sure, oysters are not the stars of premodern animal writing: they are not lions, not birds, certainly not pigs or dogs or horses. But when they do get attention, they get it as border creatures, classifiers without themselves being quite classifiable. For one, they are sexless. Thought not to reproduce “like from like,” but to generate spontaneously from the actions of celestial bodies on the water, the oyster could at least be praised for its chastity. Without the miscues of mating practiced or malpracticed by what were called the more perfect animals, oysters were perfectly suited – according to one fifteenth-century civic record from Norwich – to signify the “sadnesse and abstinence of merth [that] shulde followe…an holy tyme.” And the proverbial “immobility” of the oyster—a title bestowed on them by Boethius, Aquinas, and Higden, among others – makes them, especially, what remains “after we strip life of all its recognizable features”: this later identification is from Michael Marder, here talking not about oysters, but plants, which for him represent “life in its archaic bareness…life as survival.” Plants, however, grow in an “ineluctable bi-directionality…striving at once towards light and towards darkness”; in seeking out good land, or in breaking into stone or soil, plants evince some kind of desire, preference, or “non-conscious intentionality.” Not oysters: only the rare oyster writer suggests they rise to meet the sun or shrink from touch; otherwise, they are overwhelmingly unintentional animals, without direction, aim, or any evidence of desire. This passivity, finally, let Pliny, at one point, declare that oysters have no sensation at all, and let another, medieval writer go so far as to present them as more like stones than animals. This is Philippe de Thaon, in his early twelfth-century bestiary, which considers oysters towards its conclusion, among diamonds, beryls, and other gems. Pearls come from oysters opening themselves “de lur gré” [3036; at their own will] to the dew of the heavens, “cum fusënt vivës creatures” [3039; as if they were living creatures]. The ambiguity – this mixture of having a will and not quite being alive – neatly encapsulates the oyster’s uncertain, even universal, form of existence, which traverses life and nonlife, desire and mere mechanicity. In all this, as the sexless, immobile, even lifeless thing, the oyster is not much more than a figure of pure difference, whose only identity is that of being dubiously alive.
The mere vitality of the oyster can be better understood by contrasting it with another extreme figure of life, Lacan’s mythic lamella. In the course of his lectures on the four fundamental concepts of psychoanalysis, Lacan offers up the lamella as a correction to the fable of the origin of love told by Aristophanes in the Symposium. As he argues, sexual difference is not the origin of the drive; it’s nothing so organic and simple as that. Lacan imagines that after the gods split the first, unified people apart, something must have remained, an “immortal” drive, “the libido, qua pure life instinct,” unattached, deathless, and “irrepressible.” It is thin and flexible: the “lamella” is the gold foil buried in Greek and Roman graves, engraved with passwords for the afterlife, or even, tantalizingly, the “flesh forming the gills of bivalve molluscs, such as clams or oysters (in the class Lamellibranchia).” Just a border, a site of contact, a screen on which stimulation plays, the lamella has no particular form of its own, nor any particular aim, and therefore no capacity to satisfied. Lacan asks his audience to imagine it “envelop[ing]” their faces at night as they quietly sleep. Undoubtedly, this very creepiness makes the lamella so good to think with; as a “horrible palpitation of the ‘acephalic’ drive which persists beyond ordinary death,” the lamella represents what is so often held to be repulsive truth of the Real, the irrepressible, Lovecraftian “creeping chaos” beyond the symbolic. But the oyster, at another extreme of life, just does nothing. It has its own form, bounded by a shell. It has no desire. To extend Lacan’s myth, it is as if, with the first splitting of the conjoined humans, there were not just the one, but two things left over, the lamella, that pure form of desire, and also the life that simply wants nothing, and which is, for that reason, beneath even Lacan’s attention. Here lies something inert, undirected, less content than beyond caring, but still there and living for all that. If the lamella is a figure of “living death,” the oyster might therefore be called “deathly living” or “lifeless life,” without any of the dissatisfaction of social existence, without the motion that even a disorganized, lamellic drive demands. The oyster just sits there, wanting nothing, responding to nothing, aiming at nothing, a creature whose immobile uninterest might be recognized only retroactively as having been a form of life, only after it has been killed and reduced to a still lesser inertness.
None of this means, however, that the psychic state of the oyster cannot be represented. But what is represented, again, is a kind of border existence, an attempt to imagine the psychic life of a nullity. Efforts towards this end run from Plato all the way to the Enlightenment. Plato first describes this kind of life in his Gorgias, here imagining it not with the oyster, but rather with the charadrios, a “stonecurlew,” whose infamous habit, per one sixth-century commentator, was eating and excreting almost simultaneously. For Plato, this shore bird represented a being that functions as little more than a conduit. Because it lacks the capacity of self-mastery that would deliberately distinguish it from the rest of existence, it is helplessly, passively open, with no capacity but the unresistant, undeliberative capacity of receiving pleasure. Not incidentally, Plato’s other two examples in Gorgias include “leaky jars” and, more strikingly, kinaidos, catamites, subject to the pleasures of others, but without any of the shame or self-mastery requisite for any upstanding member of the polis. By his Philebus, these examples of a life lived only “in enjoyment of the greatest pleasures” had been reduced to sea creatures, “a mollusk” or “jellyfish” and also “one of those creatures in shells that live in the sea.” The Latin Middle Ages had access to very little of Plato’s corpus, and to the Gorgias and Philebus none at all; further work on this oyster passage would have to await the middle of the fifteenth century, with Marsilio Ficino. His Philebus commentary freely translates, equating the life of unknowing pleasure to that of “jelly fish, or a stupid living thing” [insensati et stupidi animalis], “like that of the marine oyster.” To advance his condemnation, Ficino concentrates on the jelly fish, which he characterizes as soft, delicate, easy to puncture, unable to move, with undifferentiated organs, typically found strewn on shorelines. Shaped like a lung (as the Greek pleumon or pneumon can mean both this and “jelly fish”), their shape is just that of an open sack, “semper…aperitur et clauditur,” always being opened and closed. This ongoing, indifferent receptivity, Ficino says, is an image of “the life of pleasure without wisdom…the lowest form of life, the one closest to death,” for this pleasure, enjoyed without knowledge, would be “exactly as if it were not there.” Just this side of existence, or non-existence, Ficino’s oyster is at once stolid, insensible, and flexible, shapeless, and too mobile, not quite anything in itself, yet still there for all that.
The eighteenth-century Enlightenment Encyclopedia provides two last developments of this idea, in its entries on both “innate” and “pleasure.” Diderot’s entry on the former concept observes that all that is innate to us are the faculties of sensing and touching; everything else we know is acquired through the senses. Remove sight, he observes, and all the ideas that belong to sight vanish, and so on with each sense: smell, taste, hearing, touch. Without the higher senses, abstract thought becomes impossible. Contrarily, “suppose a shapeless but sensing mass”: this mass would have all the ideas pertaining to touch, and, to this, each additional sense could be added one by one. The modes of knowledge associated with each sense would necessarily follow, with abstract ideas arising at least with a full complement of senses. Thus, writes Diderot, “through this method and through the other, we can reduce a human to the state of an oyster, and elevate an oyster to the state of a human.” Then, the entry on pleasure considers whether the pleasures of the soul surpass those of the senses. The former pleasures, alone, would give the delights of the liberal arts: history, geometry, fine letters, and an unalterable joy; the latter pleasures would, as it were, produce a being “encased in its shell,” with all its happiness resulting from the “blind” and sourd — “dull” or “deaf” — feelings of the moment. The entry bemoans humanity’s weakness. Few would prefer the former, philosophically heroic life; most would be content to experience the mere sensory “félicité” — “happiness,” or even “bliss” or “ecstasy” – “of an oyster.”
All that is left is pure sensation, the “sensus solus” which is all that most commentators grant the oyster. What this sensory power actually is, and how it has been read and misread in the millennia since Aristotle, has been studied most thoroughly in Daniel Heller-Roezen’s The Inner Touch. For Aristotle and his commentators, this fundamental “common sense” is that quality through which a sense perceives that it is sensing; his later disciples describe it as the hub to which all senses report, which establishes the possibility for communication between them, so that one and the same object might be identified simultaneously as white and sweet. For the Stoics, on the other hand, so committed to the supremacy of human reason, this sense is the one through which all living things exercise care for themselves by feeling some self-ownership. Whatever it might be—and Heller-Roezen teases it out intricately—it is not “self-awareness” or “self-consciousness.” The inner sense, this sensus solus, is more fundamental than this or any thought, because unlike thought, it cannot be removed or fully distinguished from the thing being sensed, even if it operates only by virtue of the slight gap between the sensed thing and the sensation.
With this sense, and not much else, the oyster is animal life that cannot be abstracted from its present condition. It is animal, but less mobile than a plant, since even the kelp that move in the water grow. It is alive, but seems more like a stone than an animal. Its sensitive life is bounded by a shell, which, in its helplessness, makes it most like a flapping jellyfish. Wanting nothing, it has nothing but a certain, virtually indefinable sensation. Here we have as bare a lump of life as could be imagined, with none of the vitality or striving that so often accompanies metaphors of “liveliness” or “vitality.”  What could be done with such a life, and what could possibly be owed it?
 Ranulf Higden and John Trevisa, Polychronicon Ranulphi Higden with Trevisa’s Translation, ed. Joseph Rawson Lumby (London: Longman & Co., 1865), Vol. II, 179.
 Ibid., 181. For similar statements, see Thomas Aquinas, Summa Contra Gentiles, trans. J. F. Anderson et al., 5 vols. (Notre Dame: University of Notre Dame, 1955), II.68, “How an intellectual substance can be the form of the body,” and John Weemes, The Portraiture of the Image of God in Man (London: John Bellamie, 1632), 56–57.
 For “nonfinite,” see Jacques Derrida, The Animal That Therefore I Am, ed. Marie-Louise Mallet, trans. David Wills (Fordham University Press, 2008), 5, “The list of ‘what is proper to man’ always forms a conﬁguration, from the ﬁrst moment. For that very reason, it can never be limited to a single trait and it is never closed; structurally speaking it can attract a nonﬁnite number of other concepts, beginning with the concept of a concept.”
 For pygmies, John Block Friedman, The Monstrous Races in Medieval Art and Thought (Syracuse: Syracuse University Press, 1981), 190–96; Joseph Koch, “Sind die Pygmäen Menschen? Ein Kapitel aus der philosophischen Anthropologie der mittelalterlichen Scholastik,” Archiv für Geschichte der Philosophie 40, no. 2 (1931): 209–13.
 For representative statements on the generation of oysters, Pliny the Elder, Natural History, ed. and trans. H. Rackham, 10 vols. (Cambridge: Harvard University Press, 1940), IX.LXXIV, Vol. 3:273, and X.LXXXVII, Vol. 3:413. Robert Grosseteste, On the Six Days of Creation: A Translation of the Hexaëmeron, trans. C. F. J. Martin (Oxford: Oxford University Press, 1996), 195 (for “like from like”); and Henry Buttes, Dyets Dry Dinner: Consisting of Severall Courses (London: Thomas Creede, 1599), 102; for chastity, as part of a debate in which bees, geese, flax, oysters, and other things argue over which provides more service to humans, Michael Maier, Lusus Serius: Or, Serious Passe-Time. A Philosophical Discourse Concerning the Superiority of Creatures under Man, trans. J. de la Salle [pseudonym of John Hall of Durham] (London: Humphrey Moseley, 1654), 35–36. The Latin original is Michael Maier, Lusus Serius (Oppenheim: Luke Jennis, 1619), 23.
 The quotation is from one account of the Lenten costume John Gladman supposedly wore for his January 25, 1443 revolt in Norwich; cited from Chris Humphrey, The Politics of Carnival: Festive Misrule in Medieval England (Manchester: Manchester University Press, 2001), 66.
 For Aquinas, see n2, above. Boethius, The Consolation of Philosophy, V, prose 5.
 Michael Marder, Plant-Thinking: A Philosophy of Vegetal Life (New York: Columbia University Press, 2013), 22.
 Ibid., 63.
 Ibid., 37.
 Pliny the Elder, Natural History, IX.71, Vol. 3:267, “nullum esse sensum, ut ostreis.”
 Sharron Hogan Cottin-Bizonne, “Une nouvelle édition du Bestiaire de Philippe de Thaon” (PhD Thesis, University of North Carolina, 2003). For a more easily accessible edition, Emmanuel Walberg, ed., Le Bestiaire de Philippe de Thaün (Lund: Möller, 1900). The edition in Thomas Wright, ed. and trans., Popular Treatises on Science Written during the Middle Ages (London: Y.R. and J.E. Taylor, 1841), should be avoided; Walberg observes that Wright “quelquefois mal lu,” which holds true for the section on pearls and oysters too. Cottin-Bizonne’s notes cite Isidore of Seville’s Etymologies and the Physiologus, but neither of these works include Philippe’s subjunctive assessment of the oyster’s vitality, nor anything about the oyster’s intentionality.
 Jacques Lacan, The Four Fundamental Concepts of Psycho-Analysis, ed. Jacques-Alain Miller, trans. Alan Sheridan (London: Karnac, 1977), 198.
 Darian Leader, “Lacan’s Myths,” in The Cambridge Companion to Lacan, ed. Jean-Michel Rabaté (Cambridge: Cambridge University Press, 2003), 45–47.
 Oliver Harris, Lacan’s Return to Antiquity: Between Nature and the Gods (New York: Routledge, 2017), 75, quoting Richard Boothby’s 1991 Lacan commentary. Harris, 67-75, is a particularly thorough account of the mythographic character of this Lacanian image.
 Lacan, The Four Fundamental Concepts of Psycho-Analysis, 197.
 Slavoj Žižek, The Parallax View (Cambridge: MIT Press, 2006), 118.
 For an exemplary championing of putrefaction, Ben Woodard, Slime Dynamics: Generation, Mutation, and the Creep of Life (Winchester, UK: Zero Books, 2012).
 Donald J. Zeyl, trans., Gorgias, in Plato, Complete Works, ed. John M. Cooper, Associate Editor, D. S. Hutchinson (Indianapolis: Hackett, 1997), 494b, 837.
 Olympiodorus the Younger of Alexandria, Commentary on Plato’s Gorgias, trans. Robin Jackson, Kimon Lycos, and Harold Tarrant (Leiden: Brill, 1998), 210. To the best of my knowledge, this habit is recorded nowhere else in ancient natural history. Other accounts of the charadrios—Hugh of Fouilloy, for example (De bestiis et aliis rebus, PL 177:77C) —speak instead of its diagnostic and curative potency: if it is brought to a sick person, and turns its head away, this is a certain sign that the person will die, but otherwise, it can suck out the sickness from the patient’s mouth and fly towards the sun to burn it up.
 Christina H. Tarnopolsky, Prudes, Perverts, and Tyrants: Plato’s Gorgias and the Politics of Shame (Princeton: Princeton University Press, 2010), 22.
 Dorothea Frede, trans., Philebus, in Plato, Complete Works. 21d, 409.
 Raymond Klibanksy, The Continuity of the Platonic Tradition during the Middle Ages: Outlines of a Corpus Platonicum Medii Aevi (Munich: Kraus, 1981). and the four volumes, overseen by Klibansky, of Plato Latinus, comprising translations of Meno, Phaedo, Parmenides, and Timaeus, by far the most widely read of these.
 Marsilio Ficino, The Philebus Commentary, trans. Michael J. B. Allen (Tempe: Arizona Center for Medieval and Renaissance Studies, 2000), 316.
 Henry George Liddell and Robert Scott, A Greek-English Lexicon, Revised and Augmented throughout by Sir Henry Stuart Jones, with the Assistance of Roderick McKenzie (Oxford: Clarendon Press, 1940), s.v., “πλεύμων” and “πνεύμων,” Perseus Digital Library. http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3Dpleu%2Fmwn (accessed Feb 13 2017).
 Diderot, Denis. “Innate.” The Encyclopedia of Diderot & d’Alembert Collaborative Translation Project. Translated by Timothy Cleary. Ann Arbor: Michigan Publishing, University of Michigan Library, 2004. http://hdl.handle.net/2027/spo.did2222.0000.235 (accessed Feb 13, 2017). Originally published as “Inné,” Encyclopédie ou Dictionnaire raisonné des sciences, des arts et des métiers, 8:754 (Paris, 1765).
 “Pleasure,” Ibid. Translated by Robert H. Ketchum, 2007. http://hdl.handle.net/2027/spo.did2222.0000.826 (accessed Feb 13, 2017). Originally published as “Plaisir,” Ibid., 12:691 (Paris, 1765).
 Boethius, Consolation, V, prose 5, 417, in Loeb Classical Library 74.
 For this last point, for example, The Inner Touch: Archaeology of a Sensation (New York: Zone Books, 2009), 36, 45, and 120.
 Ibid., 40, 62.
 For an exemplary discussion of resistance and unpredictability as a key feature of “life,” see Cary Wolfe, Before the Law: Humans and Other Animals in a Biopolitical Frame (Chicago: The University of Chicago Press, 2013), 32.