The Lagoon

by Armand Marie Leroi

  The problem is that here, as so often, Aristotle’s technical vocabulary is underdetermined. He’s very reluctant to coin new terms even when he badly needs them. He’s not entirely oblivious to the problem. He’ll often say that a given term is used in several different senses, and even tell us what they are – but then, as often as not, leaves us guessing which one he means.

  Indeed, there’s a third sense in which Aristotle uses eidos. It’s related to the other two, but goes much deeper, and is much more surprising. It’s the appearance of an organism, but – if this is not too paradoxical – its appearance when it cannot yet be seen. It is the ‘information’ or the ‘formula’ which was transmitted to it by its parents, from which it built itself in the egg or womb, and which it will, in turn, transmit to its progeny. It is in this sense that Aristotle thinks that the nature of a thing resides primarily in its form.

  To speak of eidos as ‘information’ risks anachronism. Aristotle certainly does not conceive of information in the general sense that we do. Yet this interpretation is supported by passages in which he draws a parallel between the transmission of animal form and the transmission of knowledge. In The Parts of Animals Aristotle considers how a woodcarver might explain his art. He clearly wouldn’t just talk about the wood – that’s merely the matter out of which it’s built. Nor would he just talk about his axe and auger – they’re merely tools. Nor would he just talk about the strokes that he makes – that’s mere technique. No, if he is really to convey the origin of the thing he’s making, he has to talk about the idea that he had when he began his work – the process by which it will unfold in his hands, its final design and ultimate purpose – he must talk about its eidos. In the same way, when a scientist seeks to explain why living things have the features they do, he must talk about their eidē. It’s just that the forms of living things are not, as Plato held, located in the mind of some divine craftsman, but rather located in their parents’ seeds.

  There’s a passage in the Metaphysics where Aristotle gives another metaphor for the relationship between material and formal natures. Rather marvellously, he compares the components of a body to a symbolic system. Some things, he says, are compounds. The syllable ab is a compound of the letters a and b. But putting a and b together is not enough to give you that particular syllable; you need something else: you need to specify the order of the letters (lest you get ba instead) or, as we would now say, you need information. In the same way, flesh is a compound of fire and earth and something else: the way in which they are ordered. And that order is the form and nature of flesh.

  Aristotle’s belief that we should attend less to the matter than to the informational structure of living things makes him seem like a molecular geneticist avant la lettre. He did not somehow miraculously anticipate the discovery of DNA: it’s mere coincidence that he used an ordered alphabetical sequence – ab v. ba – to describe forms as we describe nucleotides. Yet, in retrieving forms from the Platonic realm-beyond-the-senses, Aristotle answered, and answered correctly, the question: what is the immediate source of the design that we see in living things? It is the information that they inherit from their parents.

  XXXIV

  FOR ALL THE severity with which he handled his predecessors (and Aristotle never minced his words), he nevertheless drew on them all. Democritus and Empedocles showed him the power of matter; Anaxagoras, Socrates and Plato the prevalence of purpose; Plato the origin of order. His own explanatory scheme contains all these elements.

  It had to. The whole problem was that none of his predecessors saw that natures could be, should be, understood in several different ways. Our hearts beat – but not just because of chemistry; nor just to keep us alive; nor just because one grew in our embryonic torsos; nor even just because our parents had hearts too; rather, our hearts beat because of all of these things. All these kinds of causes complement each other, indeed, are deeply intertwined. Or so Aristotle argues in a famous methodological dictum known as the ‘four causes’. But ‘cause’ isn’t quite right: ‘four questions’ or ‘four kinds of causal explanation’ capture his meaning better:

  There are four basic causal explanations: first, what something is for (i.e. what its goal is); second, the formal cause or ‘definition of the essence’ (these first two should be treated as pretty well the same thing); third, its material basis and, fourth, its efficient cause or origin of movement.

  I take them in reverse order. The efficient (or moving) cause is an account of the mechanics of movement and change. It is now the domain of developmental biology and neurophysiology. The material cause is an account of the matter – the stuff – of which animals are made, and their properties. It is now the domain of modern biochemistry and physiology. The formal cause is an account of the information transmitted that any creature received from its parents, and that is responsible for the features that it shares with other members of its species – that is, the subject matter of genetics. The final cause is teleology, the analysis of the parts of animals in terms of their functions. It is now the part of evolutionary biology that studies adaptation. To the degree that function moulds the stuff of which animals are made, the way they develop, how they maintain themselves in the face of the world’s vicissitudes, and how they reproduce and die, the final cause embraces, as Aristotle says, the other three. He gives us the structure of our thought even when we do not know it.

  Its fault-lines too. Since its revival in the seventeenth century, biology has often been roiled by great conflicts. Many were merely arguments over how to explain. In the 1950s the battle was between the formal-materialistic molecular biologists v. teleologically minded organismal biologists. Scientists still live who bear the scars. The zoologists Ernst Mayr and Niko Tinbergen tried to broker a peace – or at least check molecular triumphalism – by arguing for the equal recognition of ‘four causes’ or ‘problems’. Their lists of causes were not quite identical and not quite Aristotle’s (they were, after all, evolutionists) but the recognition that living things must be explained in several different ways certainly is. These days, in most universities, each kind of explanation gets a department of its own.

  Is it Aristotle’s thought that has so influenced us? Some scholars, pointing to the sources of Aristotle’s system, have suggested that he was only a very industrious magpie. Karl Popper, in a fit of lèse-majesté, judged him ‘a thinker of no great originality’ (though he also conceded, with no apparent sense of contradiction, that Aristotle had invented formal logic). Plato’s fans – he still has some – are particularly prone to viewing Aristotle as his teacher’s epigone. That can be accomplished only by studiously ignoring how Aristotle transformed Plato’s ideas. As a student Darwin read, and enjoyed, Paley’s Natural Theology and may have even acquired from it his keen sense of the design displayed by living things. Yet who would call Darwin a Paleyite? Calling Aristotle a Platonist is like that.

  For Aristotle not only produced a new system of explanation, but also applied it. His predecessors viewed the world as if from Olympus. It lay far below them blurred by distance or obscured entirely by mist, and speculation filled in what they could not see. Aristotle, however, went down to the shore. He observed, applied his causes to his observations and wove them together in the books that make up his Great Course in Zoology: The Parts of Animals, The Length and Shortness of Life, Youth & Old Age, Life & Death, The Soul, The Generation of Animals, The Movement of Animals and The Progression of Animals. By the time he was done matter, form, purpose and change were no longer the playthings of speculative philosophy but a research programme.

  THE

  DOLPHIN’S

  SNORE

  DELPHIS – ATLANTIC BOTTLENOSE DOLPHIN – TURSIOPS TRUNCATUS

  XXXV

  THE BIRD HALL of London’s Natural History Museum has four old cabinets. They show three different visions of nature. The first is a walnut cabinet dating from the early 1800s filled with, perhaps, a thousand hummingbirds (but they are hard to count). Collec
ted from throughout the New World, they are mounted in crowded flights so as to suggest an impossible avian Garden of Eden or else the Heathrow Approaches. Here, the cabinet declares, is the Trochilidae in all its glory. Observe the variety and brilliance of their plumage (now dimmed by time), the varied lengths of their bills and the protean forms of their tails; observe the endless variations upon a common theme fashioned by a Creator but ordered by men. It is a very eighteenth-century vision for it represents the science of Linnaeus and Banks, their delight in the creatures of the New World and their desire to pin them down.

  The second cabinet, in the centre of the Hall, is made of oak, dates from 1881 and contains not species nor even individuals but rather body parts. The birds have been dismembered so that a duck’s webbed foot is juxtaposed against a raptor’s talons and the hook of a parrot’s bill against the slenderness of a hoopoe’s. It is an essay in functionalism. Filled with minutely printed labels, it explains with fussy didacticism why birds have the various bills, feet and feathers that they do. It must have once seemed very modern.

  The third and fourth are at the back of the Hall. The birds are mounted among branches and leaves, whole, in pairs, with their nests and their progeny. They belong to group called ‘British Birds – Nesting Series’. In one cabinet a pair of petrels crouches against Hebridean boulders; in another a blackbird peers from a hawthorn hedge as his mate stands guard over their ivory eggs. The youngest of the exhibits, they show nature as the Romantics hymned it and as we should like, but struggle to, believe it still exists, filled with animals at home in an untroubled, timeless world going about their business which is to pair and raise young. They are also a vision of England, the England of Selborne, The Hay Wain, Adlestrop and The Lark Ascending, caught on the wing and preserved in a vitrine. Upon reading the labels we learn, without surprise, that where now there are two cases once there were 159, the rest having been destroyed by the Luftwaffe in the summer of 1944.*

  BIRD PARTS. NATURAL HISTORY MUSEUM, LONDON, MAY 2010

  The beauty of living things arises from their endless variety, the sense that they give of unity within diversity, and the intricacy of their relations. In the face of nature’s munificence it’s all too easy to surrender to an inarticulate sense of the numinous connectedness of things, or else let it all surge by in a kaleidoscopic blur. Haeckel looked down upon the coral gardens of Al-Tur and babbled of the Magical Hesperides; Darwin entered the Mata Atlântica at Rio and discovered devotion – faced with a rainforest, anyone can go weak at the knees. If, however, we wish to understand the natural world, we must focus on, isolate and name its components. We must dissect, parse and label. But, as the Bird Hall shows, there are many ways to carve reality, and each cut reveals a different facet. The question that confronts us, then, is this: where did Aristotle make his cuts? What sort of science did he invent?

  XXXVI

  THE NATURAL PHILOSOPHERS of the Renaissance looked at the world with curiosity, discovered that they knew almost nothing about it and turned, quite naturally, to Aristotle as one who did. For them Aristotle was primarily a naturalist who sought to give a comprehensive account of all the creatures that he knew, but who had unaccountably failed to order his data properly.

  In 1473 Theodore of Gaza presented his translation, into Ciceronian Latin, of Aristotle’s zoological works to his patron Pope Sixtus IV. In a preface Theodore described what the books were all about:

  The rational inquiry of nature proceeds in orderly fashion through all the distinctions that nature has made so that all its living beings are diversified one from another: it groups the major genera and expounds singly the remaining aspects: it distributes genera in species and describes them one by one (and these books contain about 500 of them); it continues by explaining in which way each one reproduces (both terrestrial and aquatic species), of which limbs it is constituted, by which aliment it feeds, by what it is injured, what are its customs, how long the time it is allowed to live, how big its body is, which one is the largest and which the smaller, and the shape, the colour, the voice, the character and submissiveness; in short, it does not neglect any animal that nature generates, feeds, grows and protects.

  The false advertising is blatant. Aristotle does name some 500 ‘species’,* and does have much to say about many of them, but certainly does not describe the ‘species one by one’. Consider Aristotle on the elephant. Given that he never saw one he has much to say about it. But to find out what you must have recourse to the index, first, of Historia animalium where you find the elephant’s parts and habits dismembered and distributed throughout the length of the book:

  Elephant: age of 586a3–13; 630b19–31; mammae of 498a1; 500a17; breeding of 540a20; 546b7; 579a18–25; capture of 610a15–34; diet of 596a3; disease of 604a11; 605a23b5; driver of 497b27; 610a27; feet of 497b23; 517a31; gall of 506b1; genitals of 500b6–19; 509b11; habits of 630b19–31; hair of 499a9; limbs of 497b22; sleep of 498a9; skull of 507b35; sperm of 523a27; temper of 488a28; teeth of 501b30; 502a2; trunk of 492b17; 497b23–31; voice of 536b22 . . .

  and then to The Parts of Animals:

  Elephant: aquatic habits of 659a30; trunk and its multiple offices 658b30; 661a25; 682b35; forefeet of 659a25; foot has toes 659a25; mammae of 688b15; protected by bulk 663a5 . . .

  where its dissolution continues.* Theodore, perhaps trying to make zoology palatable to his Papal patron, disingenuously elided this arrangement and presented Aristotle as encyclopaedist. He was, in fact, promoting Aristotle as a Greek Pliny.

  In the first century AD Pliny the Elder wrote and published his Naturalis historia which, essay by essay, covered most of what he claimed it did – everything. It was a genuine natural history, probably the first. Pliny borrowed his zoology from anywhere he could and arranged it by species. He said that he valued first-hand reports, but didn’t mean it. He may well have seen elephants in Roman triumphs, circuses and battles, but this abundant source of data was for naught. A few quotes give the flavour:

  [The elephant] is pleased by affection and by marks of honour, nay more it possesses virtues rare even in man, honesty, wisdom, justice, and also respect for the stars and reverence for the sun and moon.

  [O]ne elephant fell in love with a girl who was selling flowers and (that nobody may think it was a vulgar choice) who was a remarkable favourite of the very celebrated scholar Aristophanes.

  [B]ut the biggest [elephants are produced by] India, as well as serpents that keep up a continual feud and warfare with them, the serpents also being of so large a size that they easily encircle the elephants and fetter them with a twisted knot.

  This is the authentic voice of ancient natural history: gossipy, credulous and insistent that what the author has to tell is marvellous, as indeed it would be were any of it true. If Pliny had a precursor it was surely Herodotus with his stories of gold-digging ants, griffins and one-eyed Arimaspi, and even Herodotus finds the last too outlandish for his taste.

  Yet it was Pliny rather than Aristotle who provided the model for Renaissance natural history even if it was Aristotle, happily, who provided most of the substance. In 1551 the Swiss physician and scholar Konrad Gesner published the first volume of his Historia animalium, a compendium of all that was known about the animal world. He filleted Aristotle’s works and, like Pliny, arranged his material encyclopaedia-wise. Unlike Pliny, Gesner was primarily interested in the biology of the creatures he wrote about, was commendably cautious and sought to confirm the data of antiquity; it is in his hands that the modern natural history manual takes shape. After him all that is required to give us the British Birds – Nesting Series is the perception that nature is not merely marvellous but filled with terror, beauty and pathos.

  XXXVII

  MODERN BIOLOGICAL TAXONOMY – the science of classification – began in 1758–9 with the publication of the tenth edition of Carolus Linnaeus’ Systema naturae. It set the agenda for one of the great projects of nineteenth-century science: the discovery, classification and catalogu
ing of all life on earth, a project that his successors prosecuted by publishing vast multi-volume monographs depicting nature in chromolithographed glory. Cuvier and Valenciennes’ Histoire naturelle des poissons, Voet’s Catalogus systematicus coleopterorum (2 vols, 1804–6), Esper and Charpentier’s Die Schmetterlinge (7 vols, 1829–39), Agassiz’s Recherches sur les poissons fossiles (5 vols, 1833–43), the Sowerbys’ Thesaurus conchyliorum (5 vols, 1847–87), Gould’s Monographs of the Trochilidae, or Family of Humming-birds (1849–61), Darwin’s Living Cirripedia and Fossil Cirripedia (4 vols, 1851–4), Bell’s Tortoises, Terrapins and Turtles (1872) – to name but a handful among hundreds – bow library shelves with their weight even now.

  The taxonomists, too, remade Aristotle in their own image. Their Aristotle was no mere natural historian, but the founder of their own particular science. Aristotle too, they felt, must have had the classificatory impulse, now said to be an attribute of the mildly autistic, that drives a boy to arrange and rearrange his shell collection searching for the unique organizing principle that will unify their disparate forms. He too must have felt the triumph that comes with the discovery of some creature that no one had ever noticed before, a species (delectable words) new to science, and have allowed himself the delight of giving it a name. Historia animalium must be too – though, granted, it isn’t plain to see – a catalogue.