by A. A. Long
3. THE COSMOLOGIES OF ANAXIMANDER, ANAXIMENES, AND XENOPHANES
We shall now examine some further details of the cosmologies of Thales’ successors. Like Thales, whose conception of a flat earth supported by water was probably indebted to earlier mythological world pictures, Anaximander stuck to the concept of a flat earth, which he thought of as drum-shaped, with its diameter three times its height (DK 12 A10). However, his account of the shape and position of the earth was crucially different. First of all, he dropped the entire idea that the earth needs support. This is Aristotle’s report (De caelo II295b10-16; DK 12 A26):
There are some who claim its equilibrium to be the cause of its remaining at rest – among the ancients, for example, Anaximander. They argue that that which is situated at the centre and equally related to the extremes has no impulse to move in one direction – be it upwards, downwards, or sideways – rather than in another; and since it is impossible for it to move in opposite directions at the same time, it must remain at rest.
It has been claimed that even if we knew nothing else about Anaximander, this theory alone should guarantee him a place among the creators of a rational science of the world.23 After all, he is credited with two important innovations: the (implicit) introduction of the Principle of Sufficient Reason, and the application of mathematical arguments to a cosmological question. The former claim is no doubt correct: the earth remains in position because it does not have a sufficient reason to move one way rather than another. But the second claim appears to be in need of qualification. It is true that our text refers to an argument from “equilibrium,” but it is not clear why we should conceive of this equilibrium in purely mathematical terms. Indeed, elsewhere in Anaximander’s cosmology, equilibrium appears to be a matter of opposing forces or elements (the hot and the wet), and it is plausible to assume that it is such a physical equilibrium that is at issue here as well. One might think, for example, of the mutual repulsion of warring opposites, which could explain the tendency of the earth to remain as far away from fire as possible, hence at the centre of the fiery rings of the heavenly bodies.
It may be that a similar conception of physical equilibrium was at the basis of Anaximander’s puzzling claim that the ring of the sun is furthest from the earth, and that the rings of the stars (which may or may not include the planets) were closest, with the ring of the moon in between (DK 12 A11). After all, the ring of the sun obviously contains the greatest mass of fire, and given the opposition between fire and earth, it is not implausible that in the course of the process of cosmogony such a mass of fire should have been flung furthest from the centre.24 It is also possible that this part of Anaximander’s story was simply introduced to account for the apparent fact that the lower rings do not obscure the more remote ones. He may, in other words, have argued that the brighter light of the outer rings simply shines through the comparatively modest amount of mist surrounding the lower rings of fire. Whereas the commonly accepted sequence, with the stars at the greatest distance, would have led to the objection that the sun’s ring should blot out part of the ring of the stars at those places where they intersect when seen from the earth.25 On the former interpretation, we shall have to assume that Anaximander was ready to ignore the appearances (according to which the moon is nearer than the stars) for the sake of the overall system of his cosmology; on the latter, he provided an alternative account of these phenomena. On any account, the particular sequence he plumped for appears to have been closely connected with his idiosyncratic conception of the heavenly bodies as concentric rings of fire enveloped in mist. It was not taken over by any other Greek cosmologist.
Anaximander’s attempt to specify the relative distances of these cosmic rings (DK 12 A11 and 18) has also been heralded as the first attempt to describe (part of) the orderly structure of the cosmos in mathematical terms. However, the details are very controversial and a modicum of scepticism is appropriate.26 Most importantly, we do not really know Anaximander’s arguments for choosing the numbers he put forward, and there are no indications that empirical measurements played any role.
Whether the orderly structure of Anaximander’s cosmology does or does not involve its being inherently stable, is a moot point. The context in Simplicius (deriving from Theophrastus) where the only literal fragment has been preserved allows for different interpretations. It says that Anaximander claimed that:
… the source of coming-to-be for existing things is that into which destruction too happens “according to necessity; for they pay penalty and retribution to each other for their injustice according to the assessment of time,” as he describes it in these rather poetical terms (Simplicius In phys. 24, 17; DK 12 A9; B1).
What is probably the verbatim quotation – here placed between inverted commas – decribes what is going on in what indeed are “poetical” and anthropomorphic terms. Nevertheless, the idea of time presiding like a judge over warring opposites that pay penalty and retribution for their injustice may plausibly be taken to refer to the orderly sequence of what are basically physical processes. We appear then to be told that processes of physical change, such as the gradual destruction (drying out) of moisture by fire, are reversible and will in fact be reversed. In principle this might simply mean that the predominance of one of the elements is followed by the predominance of the other, and that this process goes on ad infinitum.
However, Anaximander may also have believed that his cosmos would eventually resolve back into the boundless, and the text just quoted may accordingly be taken to refer to some sort of cosmic cycle: as soon as fire has “won” and dried out the entire cosmos, it is itself extinguished for lack of nourishment.27 Such a conception would fit in well with his conception of the cosmos as a living and generated being, for such a being would normally be bound to die and disappear again. On the other hand, it remains unclear how we should envisage the details of the process. Thus one wonders how the cosmos in its final state (either as fire or as moisture) was supposed to be taken up by the quality-less apeiron.
According to the Greek biographical tradition, Anaximander’s fellow Milesian Anaximenes was his pupil. This is how Theophrastus’ account, preserved by Simplicius, presents him (Simplicius In phys. 24, 26-30; DK 13 A5):
Anaximenes, son of Eurystratus, of Miletus, a companion of Anaximander, also says like him that the underlying nature is one and infinite, but not undefined as Anaximander said, but definite, for he identifies it as air; and it differs in its substantial nature by rarity and density. Being made finer it becomes fire, being made thicker it becomes wind, then cloud, then (when thickened still more) water, then earth, then stones; and the rest come into being from these. He, too, makes motion eternal, and says that change, also, comes about through it.
In this report, “the underlying nature” is an Aristotelian term, equivalent to “the material cause.” Our discussion thus far has enabled us to see that the application of this term, by Aristotle or Theophrastus, to Thales’ water or Anaximander’s boundless is misleading because these cover only one aspect of the Aristotelian material cause: water and the boundless are that-from-which things are, not that of which they still consist. In the case of Anaximenes, the application is more appropriate, for not only does he have the cosmos originate from air (which is testified elsewhere, DK 13 A6), but he also claims that everything in our world still is air.
For the rest there are some obvious similarities with Anaximander: the basic stuff is one and infinite (or quantitatively boundless) and also divine (DK 13 A10). Moreover, of all the then known physical “elements,” air comes closest to the qualitative indefiniteness of Anaximander’s apeiron. It is a fair guess that the particular series of rarefied and compressed forms of air of which our text speaks is based on a rough pattern of common experience: we see air turn into fire or into wind, wind into clouds, clouds into water, water into mud (earth), and mud into stone.28 However, we do not see a stone or even water turn into a plant. In these cases presumably, some kind of mixture (
the sources are silent on the details of the mechanism at work) of primary elements (e.g., earth and water) is required. There is no need to assume that Theophrastus is here projecting back the later (Empedoclean or Aristotelian) conception of elements onto Anaximenes’ system.29 On the contrary, we may note that the basic model that is at stake here can be traced back to Anaximander, whose system implies that nothing in our cosmos comes directly from the originative boundless, but that all cosmic entities are the result of the joint workings of the opposites which have in their turn come from the apeiron.
Some further remarks on Anaximenes’ application of compression and rarefaction as an explanatory mechanism. Insofar as we are dealing with a basic stuff whose quantitative changes are observed to account for alterations that are (or appear to be) qualitative, we may give Anaximenes the credit for the brilliant intuition that qualitative differences can be reduced to quantitative factors. All the same, we should note that the basic stuff at issue is not itself quality-less (as are, for example, the atoms of Democritus, which differ only in shape, size, and position), but is air. Moreover, what made later quantitative physics so successful was the application of mathematics to specify and explain the quantitative elements of the theory, and there is no trace of this in Anaximenes.
It was noted earlier that Anaximander used an element of common experience – the way water and fire interact – as the basis of his cosmogonical and cosmological explanations. Anaximenes continued on the same path and supported his claim that qualitative differences can be reduced to the quantitative process of condensation and rarefaction – and hence that air could turn into other elements when compressed or rarefied – by referring to the phenomenon that our breath is chilled when we compress it with our lips, and warm when we loosen our mouth (DK 13 B1). Anaximenes also resembles Anaximander in his use of analogy to shore up the main features of his cosmology. For he appears to have argued that just as air in the form of the breath-soul (pneuma) holds us together, so air surrounds and steers (periechei) the cosmos (B2; however, the authenticity of this ‘fragment’ has been doubted by some scholars).
Like Thales and Anaximander, Anaximenes addressed the problem of the earth’s stability: it rides on air like a leaf floating in the wind (A20).30 The same goes for the heavenly bodies, which are fiery but are supported by air (A7). Their turnings are explained by reference to currents of condensed and opposing air (A15). In abandoning Anaximander’s conception of the heavenly bodies as rings, Anaximenes returned to the traditional hemispherical conception of the (cosmos and the) sky, which he compared to a felt cap turning around our head. He accordingly rejected the idea that the sun and the other heavenly bodies move under the earth; instead, he claimed that they are carried round the earth, being obscured part of the time by the higher northern parts of the earth (A7).
We cannot here deal at length with the various detailed explanations of meteorological phenomena, or the basis of the mechanisms of evaporation and condensation, which our sources ascribe to both Anaximander and Anaximenes. Suffice it to say that the views at issue found their way into the Greek meteorological tradition: a number of them recur, for example in Epicurus’ Letter to Pythocles. The more general outlines of early Ionian cosmology did not have such a lasting impact. In the short run, however, they do appear to have influenced Heraclitus of Ephesus, whose views are discussed at length elsewhere in this book, as well as the enigmatic philosopher-poet Xenophanes, who as a young man left his native town Colophon in Ionia in 546 B.C., when it was captured by the Medes, to settle in southern Italy.
It is indeed more than likely that the latter’s critique of the traditional Greek anthropomorphic conception of the gods (DK 21 B5, 14, 15, 16) was partly prompted by the demythologizing of the physical world by the Milesians. In addition, as was pointed out above, the Milesians did not abandon the notion of divinity altogether, but introduced a reformed and “physicalized” conception of it. It is conceivable and even plausible that this helped Xenophanes to conceive of his “one god” in what may be called pantheistic terms, as a cosmic entity (this appears to be suggested by Aristotle Metaph. I 986b21-24; DK 21 A30).31 Finally, and most importantly from the perspective of this chapter, the ancient testimonies on Xenophanes’ general cosmology show that he was in many details indebted to the Ionian tradition. Like the Milesians, he defined that from which all things are, and plumped for earth and water (B29 and 33). Rather like Anaximenes he claimed that clouds are exhalations from the sea, and that the heavenly bodies are ignited clouds (B30 and 32; A32 and 40). He conceived of sea and earth as opposites, engaged in a cyclical process between droughts and floods (A33), an idea that reminds one of Anaximander. He supported this claim by pointing to the existence of fossils in stones in Syracuse, Malta, and Paros, a remarkable example of the use of empirical evidence in support of a cosmological claim.
4. MILESIAN COSMOLOGY AND THE HISTORY OF PHILOSOPHY AND SCIENCE
The picture that emerges from the previous sections shows us that despite an undeniable debt to the tradition of mythical cosmology and cosmogony, the Milesians introduced a way of explaining the physical world that was new in a number of significant respects. Nevertheless their contribution has been assessed in fairly different terms. As we noted, Aristotle thought of their materialistic cosmologies and cosmogonies as the beginning of physics, which he regarded as part of philosophy. This view is still endorsed by the majority of modern scholars, but it has had its critics.
Hegel played down the more strictly physical or scientific importance of these early theories, claiming that their main point was of a more general philosophical character.32 On the other hand, it has been argued more recently that, although we may be dealing with the beginnings of physics of science, we are not allowed to speak of the beginning of philosophy, for the simple reason that nowadays cosmology and physics no longer belong to philosophy.33 However, one wonders whether this exclusive application of the term “philosophy” in its narrow twentieth-century sense sits comfortably with the very historicity of the concept of philosophy on the one hand and the conception of the history of philosophy as a discipline sui generis on the other. Indeed, one may argue that it would amount to a relapse into the basically unhistorical practice – familiar, for example, from Aristotle – of studying the philosophers of the past from the point of view of, and only insofar as they are relevant to, one’s own philosophical views (or, more broadly, the views of the tradition or era one belongs to). Historians of philosophy, by contrast, should be able to bracket their own philosophical views where appropriate. In the present case this would amount to using the term “philosophy” not in any specific sense, but in a sense broad enough to cover what in different ages people (Aristotle, for example) were prepared to regard as philosophy.34
Also the label “science” has sometimes been denied to these early cosmologies because they were supposedly still too heavily indebted to the mythical tradition,35 or too weakly supported by observational data. The latter point is an important one that raises the question of the method applied by these early thinkers. If we adhere to what is usually called the “Baconian” picture of science – the idea that science should take its starting point through a series of controlled observations – the theories of the Milesians can hardly if at all be called scientific, for they did not practise detailed and systematic observation. At the same time, it should be acknowledged that the questions that they addressed were for the most part very general ones, such as how the cosmos came into existence. It is hard to imagine how they could have coped with such questions along Baconian lines, that is, without resorting to a fair amount of speculation. Moreover, even their more specific theories were mostly concerned with what Epicurus was later to call adela (nonevident things), that is objects that could not be observed clearly and directly, such as (the nature of) the celestial bodies. As a matter of course their theories about such objects were speculative, as indeed were those of later Greek physicists.
In our century
the Baconian theory of science has been attacked forcefully by Karl Popper, who claimed that in general science does not proceed by such simple inductive processes, and that moreover the whole question of how scientific theories originate is of no importance. Science, in his view, is a matter of daring and interesting hypotheses that are to be judged by their explanatory power and, most importantly, by whether they stand up to criticism and to tests. Popper saw the early Greek philosophers, in particular Thales and Anaximander, as the founding fathers of this kind of scientific approach. Accordingly, he presented early Greek cosmology as a critical tradition to which each philosopher made his own contribution by testing the theories of his predecessors and by coming up with alternative hypotheses. Thales, he suggests, “founded the new tradition of freedom […] the tradition that one ought to tolerate criticism.”36
But this “Popperian” picture of early Greek cosmology is as hard to defend as its Baconian counterpart. For one thing, we do not know anything about the alleged tolerance of the Milesians, whereas the evidence on their immediate successors (cf. Xenophanes DK 21 B7 on Pythagoras; Heraclitus DK 22 B40 on Pythagoras and Xenophanes) suggests a self-conscious, scornful, and satirizing attitude towards the work of others, a far cry from the gentlemanly and constructive criticism presupposed by Popper. More importantly, precisely because the theories of the Milesian philosophers were mainly concerned with quite general questions and with objects that were not clearly and directly observable, and because such observational data as were available were of a rough and general kind, we can hardly speak of hypotheses that could be tested and falsified by any kind of observational evidence.37
Where, then, does all this leave us with respect to the “method” of the early cosmologists? We may well acknowledge that they made some use of observational data to support their theories (e.g., Xenophanes on fossils) and that they often used familiar phenomena or observable processes as an analogy, and thus as an explanatory model. It is true that this does not amount to a .systematic and methodical use of observation, and it is also true that the observational data at issue in the analogies are of the same general kind as the theories themselves.38 But the introduction of observational features as such should not therefore be pooh-poohed or disparaged. It was new, it helped to make the theories more intelligible, and as such it contributed to the development of a more “rational” world view.