We come at last to the secret success of fifth century BCE pluralism: atomism. We have the advantage of hindsight here: after 25 centuries of toying with the idea that there might be some minimal particles that form the building blocks of all matter, it was discovered that atomism was true. (In the meantime, it emerged that the minimal particles were not pieces of solid matter, but themselves composed of subatomic particles: weird packets of energy. But that is a story for another time. In any case, the ancient theory led to the modern one.)
According to Kirk, Raven, and Schofield, as we have seen, the Greek atomists cut the Gordian knot by positing the existence of a void, a field of not-being. On this account, they are the most un-Eleatic of philosophers by boldly going where no philosopher had gone before and positing an infinite expanse of not-being.
But there is another way to look at what Leucippus did. Consider what Aristotle, one of our major sources on the early atomists, says about them:
Leucippus and his companion Democritus say the elements (stoicheia) are the full and the empty [or void], calling them ‘what-is’ and ‘what-is-not’; of these the full and solid are what-is, the empty what-is-not. (That is why they say what-is is no more than what-is-not, because body is no more than void.) And these are the causes of existing things in the sense of matter. And just as those who make the underlying substance one generate everything else from the modifications of this, positing the rare and dense as the modifications, in the same way these thinkers say the differences [of their elements] are the causes of everything else.[1]
What is striking about this account is that Aristotle identifies just two elements (calling them stocheia [singular stocheion], the now standard term for a basic component of matter), the full and the empty, not however many kinds of atoms might be singled out. And he makes a correlation between these elements and the dense and the rare, which had been important in natural philosophy at least since Anaximenes.
Now go back to the fundamentals of Parmenides’ cosmology. He identifies two “forms” (morphai), Night and Light, the former being dense and the latter rare. How did Leucippus arrive at his two elements? The obvious move for him to make in the wake of Parmenides’ model was to say that one of the two “elements” was, not just mostly, but completely full, and the other was, not just mostly, but completely rare, that is: empty. In other words, he took Parmenides’ model to its logical conclusion. In so doing, Leucippus provided an audacious answer to the problem of motion raised by a monistic theory of matter. How can what-is move in space if space is all full of matter? There must be empty space in which it can move. And both particles and matter and empty space must be in some sense. But if we allow a rare element to exist, what is to stop us from allowing an empty space to exist? Leucippus introduces a dualistic metaphysics that is just a modification of Parmenides’ dualistic metaphysics in the Doxa. It is, indeed, a radical modification, but in another sense, it is just the next step in a progression from a static monism to a dynamic dualism. Parmenides’ cosmology is the model, Leucippus’ cosmology the adaptation.[2]
1.5.2.4 Eleatic Pluralism
If we follow out the present line of thinking, we incorporate Parmenides’ cosmology into a theory that offers powerful new insights into how the cosmos may function. There are, according to Empedocles and Anaxagoras, determinate types of matter which can interact with each other to form either compounds or mixtures, allowing for a rich set of outcomes based on a finite set of components. The combinations of elements can be temporary or ephemeral, so long as the components themselves are everlasting. On the atomic theory, there are microscopic particles of matter that can interact with each other to form conglomerates, which can become so large as to be sensible objects. These objects will all be temporary compositions, but they will be composed of everlasting entities. Incidentally, the atoms that constitute the components of the world can, in principle, be organized into similar types so as to function as elements in a conventional sense, for instance, atoms of earth, water, air, or fire, each type having its own distinctive configuration.
We began merely with the hypothesis that the first generation of Pluralists saw themselves as followers of Parmenides’ cosmology, accepting his cosmos and its underlying physics and chemistry as a model to be followed. We have seen, I hope, that Parmenides’ cosmology potentially offers an attractive model. It differs significantly from that espoused by the early Ionians and criticized and refined by Heraclitus. That theory had seen kinds of matter being transformed into other kinds of matter, for instance Fire becoming Water and Water becoming earth in Heraclitus, where Fire, Water, and Earth were seen not as identical in some way (Aristotle sees Water and Earth as modifications or manifestations of Fire in Heraclitus). But, if Parmenides is right in his cosmology, the proper way to devise a cosmology is to posit a plurality of entities, each of which has Eleatic properties: being without generation or destruction, all alike, without change, and complete. But these permanent entities can interact to produce temporary phenomena. In place of a theory of generating substances that morph into other substances, he offers a theory of elements. In place of A becoming B becoming C, we have something like permanent entities A, B, and C that can connect with each other to make up (virtual) words and phrases.
But where is the proof? How can we establish that Anaxagoras, Empedocles, and Leucippus saw themselves as followers of Parmenides’ cosmology rather than critics of his ontology? Certainly their theories and even sometimes their words echo the pronouncements of Parmenides. There are no extant refutations of Parmenides by them. This is, to be sure, an argument from silence. The relevant passage may just have disappeared from the record. But I must point out that the ancient commentators and doxographers loved to pick up on debates between ancient thinkers. It is curious that they failed to find any disagreements between the Pluralists and Parmenides. Later Eleatics, namely Zeno and Melissus, attacked the Pluralists with Eleatic arguments. But that fact is consistent with the case in which the first generation of Pluralists saw themselves as faithful followers of Parmenides and the later Eleatics saw them as missing the whole point of Parmenides’ poem.
Even if the early Pluralists were attempting to rebut Parmenides, they adopted a great deal of Eleatic theory into their own cosmological accounts. They have been rightly described as “Eleatic Pluralists.”[3]
But aren’t we forgetting something? How can Leucippus get away with positing “nothing” as an element of equal standing with corporeal matter? Isn’t that, well, just crazy? To recall Aristotle’s report, “they say what-is is no more than what-is-not, because body is no more than void.” How can that be, given that the former is concrete stuff and the latter nothing at all?
There is an ancient fragment that gives a hint. Democritus said that “Thing is no more than not-thing.”[4] The statement amounts to a clever wordplay. The Greek word ‘nothing’ mēden is derived from mēde hen ‘not even one.’ But Democritus construed it as the negation of positive term den (which seems to have been used in some dialects of Greek).[5] Democritus seems to have recognized the possibility that the term ‘nothing’ is ambiguous at least between signifying what does not exist at all and what is not a physical object. It was only when Plato and Aristotle pointed out that ‘what-is-not’ can mean not only what in no way exists but also what is not-F or the like that there emerged a clear path to save philosophy, and maybe discourse itself, from descending into nonsense. After all, even Parmenides reasoned at length about what-is-not without, presumably, talking nonsense. It took Plato and Aristotle to disambiguate ‘what-is-not’ in a systematic way. But Democritus, at least, seems to have grasped the point that they later defended.
But there is one more argument for seeing Parmenides’ cosmology as the ultimate paradigm, one that changes everything, and yet one that has scarcely been recognized before now.
[1] Aristotle Metaphysics 985b4-13 = DK 67A6
[2] See D. W. Graham “Leucippus’s Atomism” (2008).
[3] See R. B. B. Wardy, “Eleatic Pluralism” (1988).
[4] Plutarch Against Colotes 1108f-1109a = 68B156.
[5] See LSJ s.v. deis. But it is attested as functioning only as a short from of mēden.