On "Nature" and "Theory": A Discourse with the Ancient Greeks

The Tanner Lecture on Human Values at the University of Michigan, October 30, 1998. Published with permission of the University of Utah Press and the Trustees of the Tanner Lecture on Human Values.

A remarkable paradox of our time is the growing unpopularity of science in spite of its overwhelming triumph. Citizens are easily mobilized against the nuclear industry, against genetic engineering, against chemical and medical breakthroughs (especially when they have the purpose of refashioning the human body or human consciousness)—the very fields in which science has made its greatest advances in this century. What is most disquieting is that these conflicts apparently cannot be settled by rational discussion of facts. Moral, yet irrational, impulses, fueled by suspicions of sinister special interests (money, power), lead to aggressive polemical campaigns and sometimes to coercive action. The guiding idea of our culture since at least the Enlightenment, that the purpose of science is to reveal the facts of nature, gets lost in the turmoil of controversy.

Even in the social sciences there is now a tendency to stigmatize the concept of "nature" and exclude it from intellectual discourse. "There is no human nature apart from culture." "Humanity is as various in its essence as it is in its expression."[1] These are comments by the distinguished ethnographer, Clifford Geertz. In an era of mass communications and mass mobility, culture is said to speak with many voices, with many souls, as it were. Fixed standards, assumptions, and definitions are dissolving within the multicultural conglomerate of the global village. No wonder even science itself is declared a social construct.

As cultural unanimity breaks down, cultural tradition comes under increasing attack, especially the hitherto dominant tradition of the West. Hostility from outside is met by bad conscience from inside. In the United States, Martin Bernal's accusations in Black Athena against the origins of "European cultural arrogance" in "ancient cultures of conceit" have found a large and sympathetic audience in the academy. Europe has heard the same complaints in a different key, for its geographical and intellectual proximity to the Islamic world occasions additional challenges.

Most endangered of all Western beliefs by these fractious debates is the idea of progress. Even the history of science nowadays hesitates to retell the great story of the linear ascending progress of science, culture, and society; instead we hear demands for the "contextualization" of theories and theses. Since Thomas Kuhn's landmark book, The Structure of Scientific Revolutions (1962), "the change of paradigms" has become a key phrase to characterize the ruptures and inconsistencies of scientific thinking. Granted, the investigation of personal situations and limitations within different sets of mentalities often is revealing. But it can obscure the very essence of science, which is a constantly increasing insight into "nature." Forgive me if my formulation sounds antiquated; objectivity has become an endangered species, not least in the social sciences. In the natural sciences, at least, fads and fashions do not have the power to change paradigms, nor do the social games of power and influence. Science has sponsored an evolution of theories characterized by "fitness"; fitness in relation to something we cannot but call "reality" or "nature" or even—though this sounds old-fashioned—"being." However much the concept of "nature" has come under attack, there is still no denying that means exist to prove or disprove statements and theories in general and in particular, and this is why science has been on the winning side since its earliest days. Its success should not be held against science, and its practical branch, technology, as if success were solely the result of arrogance and power. Their success is the very mark of their legitimacy.

The orientation of science toward "nature" or "reality" does not mean that its truths are absolute, but approximate and tentative. The progress of science has involved an ongoing evolution of the mind as well. Our imaginations have to be trained afresh as we encounter the quite unexpected features of reality, such as the wave-corpuscle duality or the non-Euclidean geometry of the universe. Religious and other cultural prejudices may have halted scientific progress for centuries, but there has also been the unforeseeable stubbornness of facts. Heavenly bodies do not move in perfect circles, as platonizing astronomers believed for some two thousand years; even Copernicus adhered to this notion and Galileo refused to be convinced by Kepler's ellipses. New facts compelled new theories and a new consciousness of reality.

Progress means change, and change is dangerous for life, which functions as a homeostatic system. We should not be surprised if ruptures in the social system and corresponding anxieties are consequences of scientific advances. Those anxieties ought not to cause facts to change, however. It is true that we live in a social world, amidst infinite and multiple obligations, pressures, and evasions. We are forced incessantly to play social games with changing rules. Non-human primates use practically the whole of their intelligence for their social games. Why should it be different with humans? We are all caught up in the webs of our social world. Religion has provided some openings of the closed system of social relation by suggesting an outlook founded on a non-empirical x that alleviates the distress arising from the paradoxes of existence. But religion remains dependent on dogma and authority. Science, too, presents a theoretical world independent from social differences and dynamics. That we need such a world—still a controversial proposition—is one of the powerful ideas originating in ancient Greece.

Today the comforting concept of antiquity as the cradle of our culture and starting point of progress has lost the unanimity it once enjoyed. If the Greeks are the oldest, then they are certainly the deadest of those "dead white males" that so trouble some of our contemporaries. And yet, precisely because we cannot and should not remove ourselves from the continuity of our traditions, the faint and distant voices of the ancient Greeks may clarify our unstable and "postmodern" situation. The ancient world presents simpler models that may aid us to achieve a more comprehensive perspective on the late developments in our culture that bedevil us. The Greek heritage, as is well known, has worked its spell in at least three different cultural realms: in art, in poetry, and in the world shared by science and philosophy. It is this last realm that I shall explore in this essay. I believe that the crisis of science, the crisis of "nature," and the crisis of tradition are interconnected.

 
Traditionally, the story of ancient Greece has been a great hymn to the irresistible march of progress toward rationality and humanity from a state of brute primitiveness. The popular slogan has been "the momentous leap from 'mythos' to 'logos'"—from fantastic tales about gods and the prehistorical past to a credible account of permanent nature, the foundation of civilization and of modern consciousness. We are less secure today about the essence of this progress. Traditional praise of the pageant of Greek thought has been proved to be flawed on at least three counts:

(1) The originality of the "Greek miracle" is crumbling as the older civilizations of the Near East have become better known.[2]

(2) The focus of scholarly interest in theories of culture has shifted from "classical" to "wild."[3] This shift has rekindled a special interest in myth, be it nostalgic or critical. Myth is no longer viewed as an inferior genre of primitive understanding, but as a central and persistent phenomenon in culture. This also means that the superiority of logos is becoming less clear.

(3) The rationality of the Greek achievement has been found questionable.[4] The logos claimed by the Greeks, that is, the "reasonable account" of Greek philosophy and science, can be criticized for all kinds of prejudice and blunders, deriving as it does from a society of warriors and slaveholders.

Take as an example the book on the "sacred disease" attributed to Hippocrates, a doctor of the fifth century B.C. This is a treatise on epilepsy which fervently advocates a "natural" explanation for this illness with vigorous polemics against older explanations of it as a "sacred disease" and against prescriptions for treating it with religious rituals. Epilepsy, the author writes, is not at all "sacred" but "has its nature and its cause." So far we acclaim the birth of natural science as the foundation of medicine. But when Hippocrates goes on to set out his own diagnosis, which is that phlegm enters blood vessels and causes the convulsive attacks of epilepsy, we know that his conclusions are erroneous, indeed ridiculous. The consequences of treating a patient according to Hippocrates' theory would probably be worse than letting a witch doctor chant his formulas. So where is the "progress," except for the arrogance of style? Hippocrates' rhetoric is contemporary with the political and judicial rhetoric that arose with Greek democracy; we see a different social context for medical diagnoses but we do not see the triumph of science.

Another example from the same period is the assertion that the moon shines by light reflected from the sun. Based on observation, this belief flatly contradicts the Greek name Selene, the "shining torch" of night.

One step further is the explanation of the moon's eclipses as produced by the shadow of the earth in the sky. This proposition requires some exertion of imagination to understand the interrelation of what is below to what is above the horizon, the sun standing somewhere beneath, opposite the full moon in the sky. Both theses, reflection and eclipse, were discoveries of Anaxagoras, about 450 B.C. "Things that are apparent allow a view at hidden things," he wrote. Note that the sun's eclipse is easier to understand, though it is a much rarer phenomenon: you can perceive clearly the moon covering the sun's face. (The solar eclipse was described by Thales in the sixth century B.C.)

Let us note: these are discoveries of natural facts, explanations which are simply true, even if they were not accepted by everyone at the time, and some dissent persisted for centuries. Statements of this kind are independent of varying interests at the individual or communal level. Of course there were conflicts with traditional superstitions that an eclipse is a divinely-sent "sign" which has "meaning" for king and country. One could disregard the discovery of Anaxagoras, as General Nikias did when he relied on the purported sign of the eclipse of 27 August 413 B.C. and led his army into catastrophe in Sicily (see Thucydides 7,50.4).

More radical was the thesis that the earth is a globe. We do not know for certain who first proposed that the earth was spherical. Plato knew about it in the fourth century B.C. and Aristotle had proofs both from theory and from observation.[5] He knew about an attempt at measurement—it was inexact, about 75 percent too large, but still remarkably accurate as to the order of size. Eratosthenes, 150 years after Aristotle, had the correct number; Columbus, following Ptolemy, used a smaller number for the earth's circumference, better suited to his optimism about completing his voyages. One proof for the sphericity of the earth came from the moon's eclipse: when the earth's shadow is seen in the eclipse it always appears circular, whether the full moon is high up in the sky or just at the horizon. (It would look different if the earth were a flat disk.) But remember that for two thousand years this insight about the spherical earth could not be proved directly, nor put to any practical use. Ancient ships were not equipped to sail around the globe. Not until Magellan's ill-fated voyage beginning in 1520 did a ship circumnavigate the earth. Here again, a fact was established incontrovertibly and transmitted to future generations.

Yet if Greek cosmologists agreed on the sphericity of the earth, they agreed also, with negligible exceptions, on the thesis that the earth stands still at the center of the universe. Ptolemy collected physical evidence to support this assertion. It needed the new physics developed from Galileo to Newton to dispel those assertions and make the new fact of earth orbiting the sun a permanent reality. Yet even the erroneous theory about the earth at rest should be distinguished from the pronouncement that Earth is the Mother of men, or of gods and men, or of the local polis. Myths like these have rhetorical and political purposes, not scientific ones; they exist principally to motivate patriotic war and heroic sacrifices.

The Greeks did believe fundamentally in an independent and persistent reality that should be a subject of discourse. They created the very concept of "nature." The Greeks had a word for it, physis, first used in a prominent way by Heraclitus, about 500 B.C. (The word was translated as natura by the Romans.) By etymology, physis is a form of "being"—the verbal root is identical with the English "be." The word mainly referred to the growth of plants. "Nature likes to hide," one of the most quoted sayings of Heraclitus, refers to the way plants grow in secret; if you try to observe their growth by digging up roots or unfolding buds, you destroy the plant. Growth occurs on its own, undisturbed, but according to a predetermined and repetitive course. Physis is the opposite of "manipulation." It occurs outside the conscious efforts of peoples and nations, their decrees, conventions, actions, and coercions. There exists a basic department of reality which keeps to its course and which develops by its own laws, and which sustains the life we share. You may observe it with discretion, but you cannot influence it directly, though you can destroy it. And you can put its essentials into speech; you can give an account of it. You can show by logos what the facts of the matter are; Heraclitus writes, "[I am] distinguishing each thing according to physis and declaring how it is." This susceptibility to articulation is the condicio sine qua non of discoveries, of statements that are simply true, independent of varying interests at the individual or communal level. The world of nature is represented in all phenomena which we have come to call biological, but also in the greater frame of the universe, all of which appears to exhibit some "order." It is kosmos, to put it in Greek.

The contrasting concept was termed nomos by the Greeks, meaning "law" in the sense of "convention" or "custom." This term refers to the inescapable integration of every person into the ongoing activity and limitations of traditional values and commandments. Such rules, nomoi, are dominant, though limited in scope. They account for the differences in language, customs, and character; to that extent, nomos approximates our concept of "culture." Theoretical descriptions of "society" and its functions occur in Protagoras, Thucydides, and of course in Plato. Nomos seemed necessary to them in order to counteract egoistic interests and the appetite for unlimited private profit, but one could argue that there were so many different variants of nomos that none were obligatory in general. This point is graphically illustrated in the work of Herodotus, who is particuarly fascinated with the diversity of religious beliefs and practices. He approvingly hints at tendencies to find the divine spirit in physis, in the universe and its phenomena.

Antiphon, a so-called sophist of the fifth century B.C. thunderingly denounces nomos: "In this we are made barbarians, the ones against the others; for by nature we are all organized in a similar way in all respects, barbarians and Greeks. You can observe the necessities of what is organized by nature in all humans, as it is provided by the same faculties for all of them; and in this there is neither barbarian nor Greek discriminated among us: we all breathe into the air by mouth and nostrils, we laugh when we are glad in our mind, and we weep when we are feeling distress; and by hearing we accept the sounds, and through brightness we see with our eyesight; and we are active with our hands, and we walk with our feet." Passages like this one provide an effective antidote to xenophobia. The distinction between Greeks and barbarians had long been popular in Greek culture: We, the Greeks, are the center and zenith of humanity, amidst tribes who are incomprehensible and inferior. Antiphon cleverly inverts the claim: We Greeks are made barbarians by such "cultural" distinctions, in contrast to nature which determines what is necessary and universal. The necessities of nature are not to be discussed or negotiated; they constitute the fundamental and inescapable community of mankind.

I like even better a scene from Aristophanes' The Clouds, in which the comic protagonist Strepsiades, refined by the teachings of Socrates, is approached by his banker who wishes to collect interest from a loan; Strepsiades tells him, "Look [at the sea]: Do you have the impression that the sea is fuller now than before?" No, the banker says, "it would not be natural if the sea were fuller." "Behold," Strepsiades says, "the sea does not become any larger even if the rivers are flowing into it. But you claim that your money should increase more and more [every day]." Nature is homeostatic and social and economic life could do worse than follow suit.

The discovery of "nature" in the fifth century B.C. was felt to be a kind of triumph and a source of joy. Anaxagoras was asked, "What is the sense of human life?" "To look at the sky, the stars, the moon, the sun," he replied. The Greek word for such a "look," a comprehensive, interested, yet disinterested look, is theoria. With slight changes of meaning, this word has remained another keyword in the wake of ancient Greek culture: "theory." Primarily, theoria meant to observe a festival. At Olympia, for example, there are toiling athletes, there are businessmen making money, but there are also spectators who just enjoy the free look at what is going on. A play of Euripides praised the happiness of those who manage "to see the unaging order (kosmos) of immortal physis"; such people will rise above disreputable mercenary considerations. In the Nicomachean Ethics, Aristotle, too, rated a "theoretical life" the most perfect form of human existence.

So this is, I suggest, the decisive discovery of classical Greece: the construction of a "theoretical" world which became the world of science, independent yet comprehensible, the contemplation of which leads to a unique form of personal joy. The uniqueness of the Greek project is the faith in verifiable reality, a kosmos of physis.

 
There is, however, the question of historical and social contexts to this great intellectual and spiritual experiment. Classical antiquity was not a new beginning, nor was Homer the first poet to emerge at some putative uncontaminated dawn of humanity. The Greeks were at the western fringe of advanced Asiatic cultures. Egypt, Mesopotamia, Syria/Palestine, and Asia Minor all possessed a literature of high sophistication, including forms of science and mathematics, long before the Greeks.

Take as an example a cuneiform tablet from the house of a family of conjurer-priests at Assur, in Iraq, about 650 B.C. This text, commenting on older myths, describes how the god Marduk created the universe: "At the Upper Earth he established the souls of men, in the center; on Middle Earth he made sit his father Ea, in the center." (Ea is the god of subterranean water.) "In Nether Earth he included the 600 gods of the dead in the center." Just as Thales imagined the earth resting on water, and farther down, at the lowest register, the Netherworld, so this text imagines three storeys of existence. And Heaven has three levels too; the highest belongs to Anu—he is given his Sumerian name—together with 300 other gods; Middle Heaven, made of resplendent stone, is the throne of Enlil, the active ruling god; the lowest level, made of iaspis-stone, darker but transparent, is the place of constellations. The text does not bother to explain why we see alternatively the resplendent sky at day and the iapsis-sky with stars at night.

Compare this text to what Anaximander of Miletus wrote about one hundred years later. Employing the unusual plural form, he hypothesizes three "skies" which take the form of wheels circling the earth, while the earth, a column drum in shape, is suspended at the center. The wheels, from fiery openings inside, produce the stars, the moon, and the sun, in ever-lengthening distances. If the stars belong to the smallest wheel, then there is conformity with the constellations in the lowest register of the Assur system. Even closer is the synchronism with Iranian religious lore. In Iranian texts, a sequence of "steps" marks the ascent of the soul after death toward God, via stars, moon, and sun, on up to the "endless lights." Anaximander conceives of a figure of "the Divine" that encompasses and guides everything. Likewise, Ezekiel in the Hebrew bible, speaks of the throne of God, the merkavah, its four wheels constructed "like a wheel inside a wheel . . . and the rims of the wheels were full of eyes all around." This is uncannily close to Anaximander's cosmos, though dated somewhat earlier, while God's resplendent throne recalls the even earlier text from Assur.

There can be no doubt that Anaximander's speculations belong to a context of other and earlier constructions. In what sense can we say that there is "progress" in the Greek model? The disappearance of the "underworld," as the earth shrinks to become a column-drum? More important is that Anaximander does not refer to a specific theology, to groups of recognized gods, as the Assyrian priest does, nor was he a member of a priestly family, nor was he a prophet like Ezekiel. He does not speak of the throne of God, be it Enlil, Jahwe, or Ahuramazda. Babylonian gods such as Anu and Enlil, Igigi and Annunaki would have been meaningless to him as to his public. Anaximander spoke of the "divine" as a kind of neutral abstract force, encircling and steering the universe. The personified ruling power of a religious world in eastern myth has turned into an object within a theoretical world. Anaximander modestly arranged the visible heavenly bodies in a spatial construction, in "wheels" instead of divine categories. This was evidence accessible to others, a "consensual knowledge."[6] The "wheels" introduce a mathematical element into the model; the earth cannot fall, because it is at the center, in equal distance from all sides. The figures Anaximander gave for heavenly distances are absolutely arbitrary, derived from Hesiod's Theogony, which proposed a nine days fall from heaven to earth and the same from earth to Tartaros; hence Anaximander uses multiples of nine. Of course his calculations were wrong, but they could be and were rapidly corrected. Anaximander had "discovered" the logos of sizes and distances in astronomy, as Eudemus, Aristotle's pupil, was later to acknowledge.

Just how far Anaximander was from his Greek contemporaries is another question. Phercydes of Syros invented a new mythical story in Greek about the universe, as did "Orpheus" in another key. Xenophanes heralded a supreme god to "shake" the universe; a daimon or goddess recurs in Parmenides to arrange the heavenly circles, and to procreate gods; Empedocles has Aphrodite create our world of living creatures in her workshop. If there was progress in the reduction of religious elements, clearly the steps were taken reluctantly by the Greeks themselves, and regressions remained possible. Aristotle in his Metaphysics contrasts "those who give an account of nature" with "those who give an account of gods," physiologoi with theologoi, though his own physics culminates in a theological concept, the "unmoved mover" of the universe. Plato introduced the term "craftsman," demiourgos, as creator of the universe, a concept eagerly adapted by the early Christians. It was the subsequent progress of science which has ennobled Anaximander's status, as against "Orpheus" or Pherecydes, but the progress was far from uninterrupted. Progress was possible because discussion and debate, not the obiter dicta of authority, governed the history of ideas.

 
The history of philosophy is understandably more interested in general principles than in the details of astronomical constructs. A decisive voice in the Greek concert, widely heard in the discourse on nature, was that of Parmenides. His simple thesis that "Being is, not-being is not" may seem too self-evident to stir controversy, yet it became the indispensable tenet of Greek natural philosophy: "there is no coming to be nor passing away, since there is only Being."

Even here we can find some oriental background and context for Greek forms of speaking and thinking. Already in Akkadian cosmogony we find the three concepts of "becoming" or "creating" (banu), "destroying" (halaqu), and "being there" (bashu) combined into a system; everything is bound into that pattern. In the creation epic Enuma elish, the primeval god Anshar is addressed: "You are of great heart, maker of destinies; whatever is created or annihilated exists with you."[7] Parmenides forumlates the same concept: "To become and to be destroyed, to be and not to be." Parmenides does, however, isolate "being" within the tripartite system and set it in opposition to both "becoming" and "being destroyed." This distinction, in turn, reflects categories of the Greek language, the marked contrast of the durative versus the punctual aspect. In the case of "being," language presents two roots: es- (it is) for the durative, and phy- (become), semantically related to gen- (generate) for the punctual aspect; in English both verbal roots have been mixed to form one irregular paradigm, "is" alternating with "be." For the Greeks, there is opposition: "ei gar egent, ouk estin" (if it became, it is not), Parmenides wrote, as if doing an exercise in Greek grammar. There is no physis, in the sense of "coming to be." Empedocles agreed. The Indo-European background of Greek is the reason why very similar formulas appear in Indian writings; the Baghavad Gita says, "Not-being cannot arise, being cannot pass away."

These are not idle linguistic exercises. Both in India and with Parmenides, as "being" becomes absolute, there can be no birth and no death. "Coming to be is extinguished, and perishing not to be heard of," Parmenides writes, reversing the kind of locution commonly found in works like the Odyssey: "he perished not to be known, not to be heard of" (I,242). It is the Parmenidean thesis that the inherent logic of Indo-European language excludes death. Should we say that Parmenides is using a pseudo-argument arising from the accidents of the Indo-European language to annihilate the reality of death?

Neoplatonists made Parmenides an idealist; moderns are prone to see him rather as a materialist.[8] His followers, at any rate, began to explain the natural world, with all its phenomena of coming to be and passing away, through the postulate of uncreated and imperishable constituents. Anaxagoras held that "everything" is eternally present and was there all the time, one thing contained within the other in infinitely small quanta; Empedocles thought he could make do with four elements; Democritus went further and stripped the basic constituents of qualities such as color in order to derive everything from different geometrical forms of very small indivisible particles or "atoms." We need not go into detail. Suffice to say that the diversity of theories nourished the growing body of natural science, just as these philosophers argued that any new body is the reconstituted form of antecedent forms and forces shaping it in both predictable and unpredictable ways.

But the strange and surprising fact is that the central thesis of Parmenides, his formula of indestructible being beyond birth or death, as taken up and refined by his followers, became the fundamental principle of our modern world view: the principle of conservation, conservation of mass on one side and of energy on the other, in the nineteenth century, and conservation of the duality of mass and energy after Einstein. Nothing can come from nothing and nothing can disappear. The Parmenidean postulate is by no means trivial, nor is it self-evident.

Myth tells a different story. In the Babylonian Enuma elish, for example, the gods say to Marduk: "Command destruction and creation: it will be so." A king has the power of life and death; at least his power to kill is undisputed. All the more powerful, a god can "command destruction" and it will be so. Christian theology, guided by ancient cosmogonic myth, has taken a similar view; it introduced God creating ex nihilo, and also prone to destroy his creation in the end. No, Parmenides has protested, even a god cannot work absolute annihilation, nor could he start with nothing. Our understanding of science largely agrees with Parmenides.

But there is more. Parmenides sees "being" as intimately related to speech and cognition. He insists that language is directed toward "being"; it should have a specific content or else it would be "nothing." "Objective" speech implies cognition. The impulse toward "being" also means toward truth in an absolute sense, beyond personal, social, or political concerns, the mere "opinions" of normal human beings. Ordinary people are not only mistaken in many things, they commonly hide their thoughts, emotions, and interests, in order to trick others. Parmenides insists on the strict relation of speech to "being." The Parmenidean inquirer has embarked on a lonely road, but his or her findings can be publicized in a poem which claims a "truth" beyond opinion. An elite audience will recognize this "truth" and pursue it further, as a bastion against rumor, superstition, and propaganda. This was a subversive notion of rhetoric and one with far-reaching consequences, especially for the history of science.

 
There is one field where such a pursuit rarely failed: mathematics. Euclidean mathematics is the gist of the Greek heritage. It is a very special form of logos, indeed the most successful and stable one, even if mathematics will always remain the option of a minority. It does not depend on authority, nor must it be negotiated between conflicting interests. It is independent of cultural patterns, language, race, or origin. When measuring circles, Westerners and Chinese must end up with the same value for pi.

Once again there is an oriental prelude to Greek science. In sixth and fifth century B.C. Mesopotamia, significant astronomical data were recorded and used for prediction of celestial events. The concept of the zodiac as the "path of the moon" and the "path of the sun," followed by five more planets and divided into twelve "signs," seems to have been one piece of knowledge transferred between east and west at that time.[9] There was also the mystery of the inequality of the seasons; summer, in our hemisphere, is a few days longer than winter. Kepler's discovery of the earth's elliptical orbit provided the solution to a problem that had troubled Babylonian and Greek astronomers alike.

In fact the Babylonians developed successful mathematical methods to describe heavenly phenomena, including the movements of planets, though they lacked a three-dimensional cosmic model that would provide them with general principles.[10] If natural science means the precise description of phenomena with the use of mathematics, the Babylonians are the inventors. The first Greek attempt at natural science in mathematical form, the planetary system of Eudoxos, which uses the complicated geometry of homocentric spheres, came in the fourth century B.C. Eudoxos' system is a spatial construct, visible to the mind and even constructible as a machine. It was wrong but it was soon improved, leading to Ptolemy's elaborate cosmos which became canonical for 1400 years until it was replaced by the heliocentric model developed by Copernicus. Also noteworthy were the investigations into geometry by Hippocrates of Chios, about 430 B.C., including the problems of cubic roots and the quadrature of the circle. The "classical" elaboration of geometry, the Elements of Euclid, were composed about 300 B.C.

When Archimedes discovered the formulas for the surface and volume of the sphere, around 220 B.C., he wrote, "By nature, these properties had existed before for these figures . . . but it happened that nobody realized this." He experienced the overwhelming joy of discovering what he called a "natural" fact. Since Archimedes, and thanks to him—though with less joy—every schoolchild is taught these formulas. I would like to juxtapose the remark of Archimedes with what Francis Crick wrote about the great achievement of this century's science, the discovery of the genetic code: "All the time the double helix has been there, and active, and yet we are the first creatures on earth to become aware of its existence."[11] In all probability Crick did not know the text of Archimedes; still, there is the same joy of discovery, of spelling out and representing in a working model some fundamental fact that had been there all the time. As we begin to manipulate the double helix for social ends we may feel some anxieties, but we also cannot help but share the feeling of overwhelming wonder that came with its discovery.

 
In this discourse with the ancient Greeks I have concentrated on the "glorious fifth century," on the so-called Pre-Socratics, or rather Pre-Platonics. It is true that Plato made an ambiguous intervention in the tradition I have been describing. Apparently it was Socrates who, in his protest against Anaxagoras, insisted on reinstalling the social world with its practical values, rather than honoring the world of theoria. Socrates and many of his followers distrusted the "theoretical" view, the ideal of reasonable, disinterested discourse, because it did not solve the problems of real life. "What is above ourselves, offers nothing for ourselves" (quod supra nos, nihil ad nos), the Socratic moral philosophers argued. Plato achieved a momentous synthesis of "theory" and practical philosophy. Yet granting precedence to the "Good" even above "Truth," he also opened the way to ideological dogmatism and even to totalitarian systems.[12] Plato made enormous advances in rigor of argumentation and in the use of mathematics as a decisive element in the theory of knowledge, yet his decision to develop the metaphysics of mind, mind as the bearer of knowledge, prior to matter, embedded in an immortal soul—this construct of Platonic philosophy became less and less acceptable as the scientific world view progressed. A troubling synthesis occurred when Christianity adopted Platonism, stressing the independent, responsible "soul" as opposed to the body, freeing the spirit from needs and desires, from social constraints and political power, while still demanding obedience to supreme authority and a sacrifice of the intelligence (sacrificium intellectus).

I think that we cannot and should not try to rebuild the old Platonic house for soul and mind. To assume that mind prescribes the forms of reality is no less off the mark than the Parmenidean thesis that the inherent logic of Indo-European language excludes death. But we should not be too hasty in repudiating Plato or any other classical writer. Must whole libraries of philosophical texts be condemned as antiquated? Obituaries on book culture in general are now being published, that is, on books in the Greek style: to be read, to be judged and criticized by the autonomous individual reader, books with rhetorical and personal appeal. In fact literacy had started with lists, not with literature, in the ancient orient; now we are back to accumulating massive batches of data, organized by intelligent computer programs but also subject to fortuitous "attractors" which shape dominant trends. We are close to a state when six billion individuals can simultanteously crisscross a jungle of competing and conflicting sources of information, pursuing their interests without any guidelines except financial and sexual yearnings. It seems especially strange how distinctions between "virtual" and "real" have eroded. We are caught within the World Wide Web, while the science of nature has become so complicated that nobody can "know" about it without gross simplifications. And research has become so costly that it is completely dependent on private or public financing which necessitates all sorts of political and economic strategies that precede and determine the scope of research. Nature has gone into hiding again. No wonder the theoretical world of natural science is becoming unpopular, while the social sciences have turned away from "nature" to delight in their own autonomy. The social-economic world, in its virtual expansion, is about to englobe the theoretical world entirely.

I hope that in this respect this discourse with the ancient Greeks has been illuminating. There remains the fact, even in a computer culture, that we cannot get rid of the "necessities of nature," as Antiphon said, to breathe, to eat, to hear, and to see. We remain earth-dwellers on one globe from which we cannot escape. And whether we speak of the "universe" or of "nature," we are using Greek names and concepts. Of course names are not important; but reality makes itself felt. "Nature" as a basic concern, as a power not to be disregarded, has come back with the environmental movement. Still, the "environmental" perspective remains anthropocentric, nay egocentric: nature environs us but we remain at the center. The theoretical world picture should be more capacious and imaginative.

We still require the ideal of an intelligent view of reality, and of sensible discourse, of "consensual knowledge." The continuing revelations about nature that we require as a sane goal in life are not and cannot be dependent on special varieties of race, gender, or social systems. The integrity of our humanistic endeavor depends on the individual, responsible minds of those who investigate the ongoing activity of the universe. Finally, we come back to a sentence of Plato in the Phaedrus: "Every soul has seen 'Being', or else it would not have come into human shape." The chance to catch sight of reality constitutes human dignity. I would call this the legacy of the ancient "theory of nature." I do not think that this is just Western cultural arrogance. If the Greek outlook has fertilized European mentalities, which have in turn informed the world views of every nation, then it should not be forced to hide amidst the presences of different cultural approaches or aspirations. The Greek way offers a chance of freedom in a threatening world of social and economic pressures. It postulates free discussion, free routes toward the truth. To plead, and hope, for the preeminence of intellectual culture is not to advocate the ivory tower as against the street parade; it rather means pleading, and hoping, for the eventual triumph of the most essential of human rights.

NOTES

1. Clifford Geertz, The Interpretation of Cultures (New York: Basic Books, 1973), 35. See also R. G. Newton, The Truth of Science: Physical Theories and Reality (Cambridge: Harvard University Press, 1997).

2. See Walter Burkert, The Orientalizing Revolution (Cambridge: Harvard University Press, 1993), and M. L. West, The East Face of Helicon (London: Oxford University Press, 1996).

3. The keyword comes from Claude Lévi-Strauss, The Savage Mind (1962; Chicago: University of Chicago Press, 1966); see also R. G. Hamerton-Kelly, ed., Violent Origins (Stanford: Stanford University Press, 1987), 149-76.

4. See especially G. E. R. Lloyd, Magic, Reason, and Experience (Cambridge: Cambridge University Press, 1979), and The Revolutions of Wisdom (Berkeley: University of California Press, 1987).

5. Walter Burkert, Lore and Science in Ancient Pythagoreanism (Cambridge: Harvard University Press, 1972), 303-6.

6. For this concept see Newton (note 1), page 120, referring to J. M. Ziman, Reliable Knowledge (New York: Cambridge University Press, 1978).

7. See S. Dalley, Myths from Mesopotamia (Oxford: Oxford University Press, 1989), 241.

8. John Burnet, Early Greek Philosophy (London: A. and C. Black, 1930), 182.

9. We know about a sixth century poem on the zodiac by Kleostratos, and the first horoscopes in cuneiform are dated to 409 B.C. See Frances Rochberg-Halton, "Babylonian horoscopes and their sources," Orientalia 58, 1989, 102-23.

10. For deductive proof as a Greek discovery see B. L. van der Waerden, Science Awakening (New York: Oxford University Press, 1961), as well as the qualifications in H. J. Waschkies, Anfange der Arithmetik im Alten Orient and bei den Griechen (Amsterdam, 1989), 302-26, and Newton (note 1), 137-9.

11. Francis Crick, What Mad Pursuit (New York: Basic Books, 1988), 62.

12. This was the accusation of Karl Popper in The Open Society and Its Enemies (1945; Princeton: Princeton University Press, 1963). See especially part I: "The Spell of Plato."