ONE WORLD OR INFINITE WORLDS

As noted above, the explicit references of various classical authors to multiple or even infinite (innumerable, boundless, countless) worlds has provoked among contemporary scholars a debate on whether Anaximander conceived of just one world or many, and, if so, what kind of infinite worlds he had in mind. Over time, three main possible interpretations of Anaximander's thought have emerged. According to the first, there exists only one world, which came into being and will eventually perish, but its demise will be followed by the formation of another world. These worlds are thus successive. The second interpretation proposes that at any one time there exists an infinite number of worlds which come into being and in turn perish. This conception emphasizes coexistent worlds but also includes successive worlds. The third interpretation claims that there exists only one world, which came into being and is subject to changes, but does not perish.

Edward Zeller in his time defended the successive-worlds interpretation. His view was espoused by Francis Cornford, who argued that the idea of infinite coexistent worlds emerged only in post-Parmenidean pluralism,Footnote ³ and a similar position was supported by David Furley and Aryeh Finkelberg.Footnote ⁴ The interpretation involving coexistent worlds, on the other hand, has been defended by John Burnet and subsequently also by Martin West and Marcel Conche.Footnote ⁵ Richard McKirahan arrived at the same conclusion, based both on the number of references that ascribe to Anaximander belief in coexistent worlds and on an interpretation of τὸ ἄπειρον as infinite space.Footnote ⁶ Gad Freudenthal in this context mentions a biological-botanical interpretation of Anaximander's cosmogony, within which there is no reason why a world-seed should appear in one place rather than in another.Footnote ⁷ Edward Hussey, too, ascribes to the Milesians a belief in boundless coexistent worlds, since in a boundless universe there are no unique places.Footnote ⁸ Geoffrey Kirk, on the other hand, claims that Anaximander did not believe in any kind of infinite worlds but only in one world and its changes.Footnote ⁹ His position was later espoused by several scholars, most notably Charles Kahn, and recently by Andrew Gregory.Footnote ¹⁰

HEAVENS AND WORLDS

The notion of a plurality of worlds or infinite worlds appears in various texts dealing with different aspects of Anaximander's thought, especially those that touch on the subject of the ‘source’ (ἀρχή), or are concerned with cosmology. Let us now focus on the issue of the ‘source’. The idea of multiple worlds was ascribed to Anaximander by Simplicius in his commentary on Aristotle's Physics, which he based on Theophrastus:

It is usually assumed that Simplicius is the best source for Theophrastus’ original text, while other authors, most notably Hippolytus, record less accurate versions. Hippolytus writes:

Although in the key phrase ‘heavens and worlds’ this version preserves a singular κόσμον, which is found in the Diels–Kranz edition, Marcovich's edition changes it to a plural. This is because the plural, κόσμους, appears not only in the immediately following sentence but also in the works of Simplicius, Ps.-Plutarch and Aetius. Hippolytus also does not initially use the term ἅπαντας, but in the following sentence speaks of πάντας.

Interestingly, neither of the texts speaks about infinite worlds as such—they both note only that the posited worlds are multiple. The first explicit reference to infinite worlds appears in Ps.-Plutarch, who—like Simplicius—uses the term ἅπαντας, but relates it to κόσμους, not to οὐρανούς:

A significantly modified version of Theophrastus’ text also appears in Aetius:

Although Aetius does not use the term οὐρανοί, he does speak, like Ps.-Plutarch, about ‘countless worlds’. Moreover, he mentions not only their coming to be but also their demise. This is indeed the first time when we find an explicit reference to worlds perishing—into the boundless.

It is not clear whether the texts quoted above refer to successive or to coexistent worlds. What is evident, however, is that Theophrastus ascribes to Anaximander the phrase ‘all the heavens and the worlds in them’. These heavens and worlds are generated from the boundless nature that, according to Hippolytus, surrounds all the worlds. Similarly, Aristotle in his De caelo claims that the boundless nature encompasses ‘all the heavens’ (πάντας τοὺς οὐρανούς).Footnote ¹⁵ Both of the Peripatetic thinkers use the expression ‘all heavens’, a phrase usually linked to a theory of infinite worlds, which had become the target of Aristotle's polemic (Cael. 1.7–9). Before turning our attention to further fragments, we should therefore pay close attention to two key terms, namely ‘heavens’ (οὐρανοί) and ‘worlds’ (κόσμοι), and try to outline their possible meaning in the context of Anaximander's thought.Footnote ¹⁶

The term οὐρανόςFootnote ¹⁷ (‘heaven’, ‘sky’) can refer to the celestial vault or the seat of the gods. Aristotle distinguishes three meanings: in addition to the sphere of the fixed stars, that is, the border of the world, it can also mean the sphere of the Moon, the Sun and the planets, or the whole ‘world’, the ‘universe’ in general.Footnote ¹⁸ At first sight we might be inclined to focus on ‘heavens’ (οὐρανοί) in the sense of a sphere of celestial bodies and ‘worlds’ (κόσμοι) in the sense of distinct worlds. The whole report would then amount to a claim that individual worlds, which contain heavens, are generated from the boundless nature. This reading, however, seems to contradict the formulations found in Simplicius and Hippolytus, who speak of a plurality of heavens containing worlds or a world. It is thus not a world that contains heavens but the other way around. Ps.-Plutarch then somewhat obscures the issue of the relationship between worlds and heavens by including a general statement about their origins, where his use of language almost seems to imply that the expression κόσμοι should be understood as a general term for οὐρανοί.Footnote ¹⁹

Given the possible meanings of the preposition ἐν, Richard McKirahan concluded that this phrase refers to the coming into being of heavens and worlds or world-systems ‘located there’, that is, the generation of individual worlds with their associated heavens that partly constitute them.Footnote ²⁰ Geoffrey Kirk, on the other hand, proposed that Aristotle may have been using the term οὐρανοί in analogy with Anaximander's circles of heavenly bodies in his own technical sense as an expression for the spheres of heavenly bodies, but that what he had in mind was just one world consisting of these spheres, that is, ‘everything enclosed by the first heaven’.Footnote ²¹ Theophrastus and other authors may then have assumed that what was meant were the individual first heavens, each enclosing a world.

The issue becomes more complicated once we start investigating whether both terms were being used in a Peripatetic sense. In Simplicius the whole sentence is introduced by the phrase ‘he says’, which is followed by fragment B1. This might imply that the text includes some of the original language. The term κόσμος may thus have been used in its archaic sense of ‘order’ rather than in the sense of a ‘world’.Footnote ²² It is generally assumed that the term κόσμος started to mean ‘world-order’ or ‘universe’ only from about the mid fifth century b.c.e.Footnote ²³

In general, one can assume that, although both terms are used in a Peripatetic sense—which is how Simplicius too would have doubtless understood them—they are not used arbitrarily. In fact, we shall see that they emphasize some particular motifs from Anaximander's conception. Having adopted Edward Zeller's position, Francis Cornford believed that the term οὐρανοί referred to the individual circles of heavenly bodies which form a universe, while κόσμοι denoted the regions of one such world surrounded by these circles. According to Charles Kahn, the term κόσμοι similarly applies to the lower ‘ordering’ of the atmosphere, land and the sea. For instance, when Aristotle in his Meteorologica speaks about ‘those who maintain that at first the earth also was moist, and that subsequently the universe about the earth (τοῦ κόσμου τοῦ περὶ τὴν γῆν) was heated by the sun’,Footnote ²⁴ the term κόσμος refers to a region that surrounds the Earth, and could therefore be interpreted as referring to distinct regions within one world. If, according to Anaximander, the Earth also has an opposite surface,Footnote ²⁵ then, given Anaximander's penchant for symmetry, it is possible that such individual regions found within the circles of heavenly bodies may have even been doubled.Footnote ²⁶

Simplicius’ report as a whole is influenced by Peripatetic terminology. It is of an informative nature and focusses on the subject of the principle. At first sight, then, it does not seem that Simplicius is using the term οὐρανοί to refer to Anaximander's system of circles of heavenly bodies, and it is unlikely that the term would have been understood that way by his readers. If Simplicius indeed ascribes to Anaximander a belief in infinite worlds, Kirk's proposal as explained above is a natural interpretation. If, however, Simplicius intended to emphasize only infinite worlds, he could just have used the term κόσμοι (since there was no need to speak also of the οὐρανοί). They are, moreover, quite explicitly ‘many’, not infinite. If both terms refer to cosmology, one might well ask why Theophrastus uses such complex phraseology. Instead of using both terms, he could have provided just a general description of the ‘generation of all there is’ from the boundless nature. In short, the distinction between the terms οὐρανοί and κόσμοι is curious because the point of the use of both is not obvious from the context.

Yet, if we suppose that the term κόσμοι is related here to fragment B1 which follows, we can conclude that what is meant here is a general Peripatetic statement regarding the coming to be of all the spheres of the heavens and regions of the world within them. Existing things then come to be from those regions. In Anaximander's case, this is a literal statement, since he seems to claim that life arose from the moist environment of mud. Such a reading might help to explain the problematic sequence of the individual sentences in Simplicius’ report. If we assume that the pronouns in both ‘from what’ and ‘into them’ refer to the κόσμοι, we could interpret fragment B1 as stating that existing things are generated from ordered regions (κόσμοι)—in particular, from mud—and that they, that is, existing things, also eventually perish into those regions. Furthermore, although a description of the principle from which everything arises would require the use of just one of the terms, this interpretation could explain the employment of both the οὐρανοί and the κόσμοι. The report thus contains a general Peripatetic description of the universe in the context of the term οὐρανοί, whereas the term κόσμοι refers to its particular ordered regions. Fragment B1 then explains what happens in these regions.

Although this reading describes the coming to be of one world, it does not exclude the possibility that Anaximander believed in infinite worlds. There are other texts that ascribe this claim to Anaximander, and these are texts where κόσμος demonstrably means ‘world-order’.

INFINITE WORLDS

Once we turn our attention to further texts, mainly pertaining to cosmology, we see that most of them contain only the term κόσμοι used clearly in the sense of ‘world-orders’. These passages appear largely in the works of Simplicius and Aetius, who thus narrow down the problem to a question of infinite worlds, either coexistent or successive.

When Aristotle in his Physics discusses his predecessors’ views of the eternity of motion or its beginning and end, he also touches on the subject of infinite worlds:

Aristotle does not refer here to any particular thinkers and in the following passage mentions only Anaxagoras and Empedocles, who are said to have believed that motion need not always have been present. By contrast, Simplicius in his commentary presents a classification of particular conceptions and lists thinkers who held the views in question. He starts with a conception involving infinite worlds and eternal motion, and ascribes this view to Anaximander and the atomists. What he has in mind are clearly coexistent worlds. This supposition is further supported by his description of the worlds as ‘some … others’:Footnote ²⁸

Simplicius goes on to distinguish between various conceptions of a single world, listing Plato and Aristotle as proponents of an eternal world and eternal motion.Footnote ³⁰ Then he describes the concept of a world that lasts eternally in a series of individual worlds, whereby motion is equally everlasting:

Simplicius subsequently mentions Empedocles, who is said to have defended the notion of a discontinuous series of one world and motion, determined by the alternating existence of the Sphairos and the rule of Strife.Footnote ³² The last conception that he presents is said to have been advocated by Anaxagoras, Archelaus and Metrodorus of Chios,Footnote ³³ who allegedly postulated just one world that has a beginning in time, as motion does.Footnote ³⁴

Simplicius touches on the issue of Anaximander and infinite worlds again in his commentary on Aristotle's De caelo (Cael. 271b1), where he investigates the possibility of the existence of an infinite body:

This time Simplicius slightly distances himself from the ascription of infinite worlds to Anaximander by saying that he ‘seems to …’. At the same time, he contrasts the two Milesian philosophers, although their principles should have been similarly infinite. He rejects the idea that Anaximander believed in one infinite world and ascribes to him a view that posits worlds ‘infinite in number’. Since he also describes his principle as ‘infinite in magnitude’, this could support a hypothesis of coexistent worlds.

In his commentary on Aristotle's De caelo, Simplicius returns to Anaximander in a discussion of the elements, where the issue of infinite worlds also resurfaces:

Once again, Simplicius expresses a degree of caution by using the phrase ‘as it seems’. In this text, however, the connection between the infinite (or boundless) and the generation of worlds seems to imply successive worlds. We have seen that Aetius expresses himself in a similar vein. Aristotle in his Physics lists a similar reason for postulating the infinite,Footnote ³⁷ and although he eventually rejects this notion because of his belief that the universe is finite, it confirms the authenticity of that conception.Footnote ³⁸

Aetius too attributes to Anaximander a conception of infinite worlds in several places. He uses the term κόσμοι in a passage where, like Simplicius, he links Anaximander with the atomists and several other thinkers:

This is a version of Aetius’ text preserved in Stobaeus as it appears in the Mansfeld–Runia edition. Stobaeus himself, however, leaves out Metrodorus and instead of περίστασιν, which appears in the Mansfeld–Runia edition based on Ps.-Plutarch, uses the expression περιαγωγήν.Footnote ⁴⁰ Ps.-Plutarch, on the other hand, mentions only Democritus, Epicurus and Metrodorus. A comparison of the two versions of Aetius shows that, while Ps.-Plutarch immediately above states that ‘Thales and his successors (declare that) the cosmos is unique’,Footnote ⁴¹ Stobaeus mentions in addition to Thales also Empedocles, Heraclitus, Anaxagoras, Plato and Aristotle.Footnote ⁴² Whereas Simplicius defines in his classification several subgroups, Aetius distinguishes only two, namely thinkers who hold that there is only one world and those who believe that there are infinite worlds. Empedocles and Anaxagoras are thus in the same group as Plato and Aristotle. Francis Cornford therefore believes that it is possible that, whenever Aetius found the phrase ἄπειροι κόσμοι or ἄπειροι οὐρανοί, he associated the author with the atomists.Footnote ⁴³

Meanwhile, the nature of the infinite worlds mentioned in Aetius’ text depends on our interpretation of the phrase κατὰ … περίστασις or περιαγωγή. The term περιαγωγή can be interpreted in this particular context in the sense of ‘in every direction’, as McKirahan suggests,Footnote ⁴⁴ or an ‘interval’, eventually ‘with every circulation’, as DK and TP add. Infinite worlds thus come to be and perish in every circulation, and this comes close to the meaning of Simplicius’ text quoted above (In Arist. Ph. 1121.5 = DK 12A17).

In Aetius, we can focus on yet another text, which again contains the term οὐρανοί:

This, however, is a version of Aetius as preserved in Stobaeus. Ps.-Plutarch and Eusebius do not use the term ἀπείρους and instead speak of stars. That changes the meaning of the whole passage to:

We could consider one of the meanings of the term οὐρανός: it can be used to refer to heaven as the seat of the gods. In this context, stars could mean the circles of the stars, especially if Stobaeus hints at their infinity. What we thus probably see here is a conjunction between a late meaning of οὐρανός in the sense of a heavenly sphere and a more general tendency to associate stars with gods. Ps.-Plutarch's and Eusebius’ version could thus help explain the term οὐρανοί and the way in which one should interpret it in the context of Anaximander's thought.Footnote ⁴⁷

The last of Aetius’ texts that we need to consider more closely is preserved only in Stobaeus:Footnote ⁴⁸

Since Aetius immediately thereafter adds that according to Epicurus worlds are not at an equal distance from each other, one can indeed assume that he has spatial distance in mind.Footnote ⁵⁰ This is why the passage is commonly interpreted as Aetius reporting that Anaximander believed the distances between circles of heavenly bodies to be equal. On the other hand, since temporal cycles are mentioned elsewhere, one cannot exclude the possibility of a temporal sequence of individual worlds.

The subject of infinite worlds is also mentioned by Cicero and Augustine. Cicero, like Aetius, mentions gods in this context:

In order to ascertain whether this text speaks of successive or coexistent worlds, we must first see whether interuallis should be interpreted in a spatial or a temporal sense. Although in Aetius we have seen references to equal or unequal distances, it need not be the case here, especially given the reference to birth and perishing. A replacement of mundos (κόσμους) for caelos (οὐρανούς) and an interpretation of interuallis in the sense of intervals of time—which is a reading proposed by Francis Cornford—would make good sense and would be compatible with the description of stars as found in Aetius.Footnote ⁵²

Augustine makes some interesting points regarding Anaximander's principle:

In this text, intervals between worlds are clearly temporal; even so, it is not quite clear whether what is meant are worlds that succeed one another or that exist separately, as in atomist theories. None the less, here we find an emphasis on the uniqueness of each world, among other things in terms of its duration. It is suggested that not all worlds persist for the same length of time.Footnote ⁵⁴

All these texts have provoked debate regarding what kind of infinite worlds Anaximander envisaged. Although belief in infinite worlds had been attributed also to other ancient thinkers (and such references were mostly rejected by modern scholars), in the case of Anaximander such ascriptions are, owing to the large number of texts that mention this subject, usually accepted as genuine. In this context, it can be assumed that the texts confuse and interchange various meanings of the term κόσμοι and speak of different subjects.

INFINITE COEXISTENT WORLDS

Let us start by focussing on a view that posits infinite coexistent worlds. Simplicius ascribes this position to Anaximander explicitly, thus grouping him with the atomists. Based on their conception of what there is, atomists believed that in an endless universe there exists an infinite number of worlds.Footnote ⁵⁵ The term κόσμος in this context designates a concrete ‘world’ consisting of individual celestial bodies. There are countless distinct worlds, which come into being and perish independently of each other.Footnote ⁵⁶ Our world, which consists of the Earth in a central position around which other celestial bodies circle, is enclosed by its own heavenly vault with the stars. Other worlds are not and cannot be directly experienced. Their existence is assumed purely speculatively as a consequence of the atomistic theory as a whole.Footnote ⁵⁷

In the case of atomists, we have concrete sources that mention the shape and form of the other worlds posited, but in Anaximander's case we have only general remarks regarding infinite worlds. If the atomistic conception allows for the assumption of infinite coexistent worlds, then, we should investigate whether Anaximander's cosmology includes similar features warranting the same conclusion, that is, the existence of coexistent worlds. Anaximander envisioned a universe with a flat Earth in the middle, around which revolve heavenly bodies in the form of gigantic fiery circles surrounded by foggy air. Closest to the Earth are the stars followed by the Moon, while the circle of the Sun is furthest removed from the Earth.Footnote ⁵⁸

In this conception, it is not clear whether the universe is enclosed by a heavenly vault, albeit one that does not carry the stars. At first glance, an open universe without a vault seems at least compatible with the hypothesis of infinite worlds. If, however, Anaximander indeed assumed the existence of individual coexistent worlds, this raises the question of his idea of their individual borders or limits, especially if they are not enclosed by a vault. The point can be illustrated by the case of Leucippus, who imagined a similar sequence of heavenly bodies in relation to the Earth, that is, the Moon being the closest, followed by the stars and the Sun.Footnote ⁵⁹ Aetius and Diogenes Laertius ascribe to him a belief in a membrane that encloses the world.Footnote ⁶⁰ While it is possible that in Anaximander's case references to such borders simply did not survive, their absence may be interpreted as indicating that he believed in only one world.Footnote ⁶¹

Another indication of the possibility of infinite worlds could be the presence or absence of the centre of the world, a notion which, as Aristotle notes, loses meaning in an endless universe. To Anaximander, however, Aristotle explicitly ascribes a limited world with the Earth at its centre.Footnote ⁶² The central position of the Earth in Anaximander's conception of the universe is supported both directly and indirectly by several other authors,Footnote ⁶³ but even if they are right, this feature of the universe does not help us decide the issue because each world could have its own centre. None the less, no known text pertaining to the stability of Earth, a notion proposed by Anaximander and recorded especially by Aristotle,Footnote ⁶⁴ implies that such stability holds within each of the eventual universes. Surviving texts rather clearly seem to speak only of one single world.

All in all, reports about Anaximander's cosmology do not prima facie support the theory that he believed in infinite coexistent worlds. They merely do not rule it out. Surviving texts do not mention any particular features of the coexistent worlds, as in the case of atomists. They all refer to just one world. Given the generally meteorological character of Ionian cosmology, which assumed that heavenly bodies are in close relation to the earth and the sea, and that the universe is one continuum, one might thus conclude that the texts describe just one existing world. Moreover, another hint could be the general tendency of archaic cosmologies, which tended to presuppose a smaller, well-defined world.Footnote ⁶⁵

Anaximander is a thinker of another era, of a time before Parmenides developed his thoughts and others elaborated the consequences of his ideas. We have no proof that anyone prior to the atomists believed in the existence of coexistent worlds. It thus seems unlikely that the notion was first proposed by Anaximander during the Archaic period, and then for a long time he was its only proponent. It is much more likely that a later atomistic conception was erroneously ascribed to Anaximander because of certain similarities between his notions and those of the atomists.Footnote ⁶⁶

ONE ORDERED WORLD

Let us now investigate the possibility, formulated by G.S. Kirk, that Anaximander presupposed the existence of only one world, which came into being and is subject to various changes, but does not perish. This is relevant because belief not only in coexistent but also in successive infinite worlds may have been ascribed to Anaximander by mistake. Kirk's theory is indirectly supported by the fact that there are hardly any references in Aristotle corroborating the notion of infinite worlds in Anaximander's thought. In fact, some grounds for such a supposition can be found only in one passage where Simplicius ascribes to Anaximander the notion of a ‘middle element’:Footnote ⁶⁷

If the whole theory was based solely on texts related to Theophrastus, it is possible that commentators may have erroneously elaborated some notion proposed by Aristotle. In this context, the polemic in the Physics Footnote ⁶⁹ related to the fifth reason in favour of boundlessness—where Aristotle mentions the existence of the boundless outside or beyond the heavens—seems particularly germane.Footnote ⁷⁰

Although this passage is usually interpreted as referring to atomists, the boundlessness of Anaximander's principle could be significant. It could have been the reason why some version of the notion of infinite worlds was ascribed to the Milesian philosopher. On the other hand, if elements in general were seen as infinite in size, the same reasoning should have been ascribed to the other Ionian thinkers too, but this is not the case.Footnote ⁷¹

One can thus suppose that the ascription of infinite worlds to Anaximander was linked to his cosmology, which was based on the notion of circles of heavenly bodies. Although this hypothesis was formulated many times, scholars have tended to neglect the unique nature of Anaximander's conception, even though it is this that probably underlies all of the cosmological reports. In comparison with other contemporary cosmologies, Anaximander's proposal is alone in assuming that heavenly bodies pass under the Earth. This makes heavenly bodies not just products of evaporation but concrete objects. Their separate existence of these bodies may have given rise to an erroneous supposition that Anaximander believed in infinite worlds.

Anaximander's conception of the universe may have evoked the idea of coexistent infinite worlds, which is what Simplicius erroneously assumed, while not actually involving it. In the case of successive worlds, what seems to be of decisive importance is the issue of a world coming to an end. If we adopt Kirk's position and assume that according to Anaximander the world came into being, undergoes various transformations, but does not and will not perish, the issue of the world's end becomes absolutely crucial. If we were able to reject the idea that Anaximander's world can end, it would significantly support Kirk's suggestion.

Aristotle claims that all his predecessors agreed that the world came into being, but differed in their views regarding its termination:

Although Aristotle does not name any thinkers who believed that the world was everlasting, Simplicius in his commentary mentions not only Orpheus and Hesiod but also Plato.Footnote ⁷³ Simplicius associates the first of the two ways in which, according to Aristotle, the world might conceivably end, with the atomists, on the grounds that, if objects are composed of atoms, once perished and defunct they cannot come into being again.Footnote ⁷⁴ The second way, which assumes an eternal sequence of coming into being and perishing, is ascribed by Simplicius not only to Empedocles and Heraclitus—as it is by Aristotle—but also to the Stoics.Footnote ⁷⁵ In contrast to the passage from Simplicius’ commentary on the Physics (In Arist. Phys. 1121.5–17) quoted above, here he lists only atomists and makes no distinction between the positions of Heraclitus and Empedocles. Aristotle himself subsequently adds that a claim that the world repeatedly comes into being and perishes is equivalent to assuming that the world is eternal, although subject to changes of shape.Footnote ⁷⁶ This ‘correction’ could be seen as a confirmation of the authenticity of that conception.

Elsewhere, in connection with coming into being, Aristotle makes the general claim that according to Hesiod's followers and the first natural philosophers everything comes into being, but some things persist while other things perish.Footnote ⁷⁷ Although we might assume that the Milesian philosophers would be included in this group, Simplicius ascribes to them as natural philosophers sensu stricto a position that Aristotle asserts was held, among ‘many others’, by Heraclitus of Ephesus. According to this view, everything comes into being and is resolved into a ‘thing’ which truly endures and whose transformations give rise to everything else.Footnote ⁷⁸

This argumentation is based on a Peripatetic conception of substance, but, as we are about to show, it may be illuminating to consider a possible link between the Milesians and Heraclitus. Although we have no reports on how Anaximander may have imagined the end of the world, it has been suggested that he may have thought it would happen through the drying out of the earth. This seems to be implied by Aristotle in his Meteorologica, when in connection with Ionian meteorology he discusses a view according to which the sea will gradually dry out:

Aristotle ascribes this notion only to Democritus, but Alexander of Aphrodisias with reference to Theophrastus also names Anaximander and Diogenes of Apollonia. Although the reference to Anaximander could be doubted, it is usually accepted based on Alexander's explicit reference to Theophrastus.Footnote ⁸⁰

These texts deal with the gradual evaporation of the sea, that is, the primal moisture in the world. We are not informed in them, however, whether all moisture is supposed to dry out and cause the world to perish. The drying out of moisture by the fire of heavenly bodies, meanwhile, would lead not only to the demise of the earth but also to the end of the world as such, since moisture is one of the basic constituents needed for its functioning and continuation. It is possible that this is just a description of the periodic changes which the surface of the Earth undergoes, but Aristotle and Alexander of Aphrodisias at least suggest a way in which the end of the world might be envisaged.

Although we have no report detailing specific ideas of the end of the world, some of the texts mentioned above do pertain to the coming into being or the end of the world or worlds on a general level. While they mainly emphasize the generation of the heavens and the worlds from the boundless, Ps.-Plutarch speaks of the coming to be and perishing of all there is, and Aetius even explicitly refers to the decline and ending of worlds. In another place, Aetius even includes Anaximander among thinkers who believed that a world could end:

This, however, is just a version of Aetius preserved in Stobaeus and one cannot place much trust in such a general claim regarding the possibility of the end of the world. Although the issue of the world coming to an end could be also linked to the interpretation of fragment B1, that will probably remain the subject of various inconclusive speculations.

All the same, Kirk's suggestion of one ordered world subjected only to local changes could itself be based on excessive extrapolation of Anaximander's fragment B1 interpreted in the sense of a description of a continuously reaffirmed order. Moreover, if we do accept the notion of one stable persisting world, we run into problems regarding the distinction between the boundless (τὸ ἄπειρον) and existing things, that is, also the whole world.Footnote ⁸² To wit, the boundless—unlike everything else—is explicitly exempted from coming to an end. Aristotle characterizes it as being ‘without coming to be and perishing’ (ἀγένητον καὶ ἄφθαρτον), ‘for it is deathless and imperishable’ (ἀθάνατον γὰρ καὶ ἀνώλεθρον).Footnote ⁸³ Hippolytus similarly emphasizes that the boundless is ‘everlasting and ageless’ (ἀίδιον καὶ ἀγήρω),Footnote ⁸⁴ while according to Ps.-Plutarch ‘that which is generative’ (τὸ γόνιμον) separates from ‘the everlasting’ (τοῦ ἀιδίου), which is commonly believed to represent the boundless. In the case of all other existing things, on the other hand, Hippolytus states that they come to be and their duration is limited.Footnote ⁸⁵ If the boundless were to ‘contain all things and steer all things’,Footnote ⁸⁶ it may appear that it could be responsible for maintaining the continuity of the world. One can, however, suppose that such a role would clash with its status, radically different from temporal things and the world.

It thus seems that different references to time found in the texts could be important. If they refer to coming to be and perishing within a certain period of time, one could suppose that on a larger scale they might also apply to the perishing of the world.

SUCCESSIVE WORLDS

References to time and temporal cycles appear in truly key texts, the best known being fragment B1. Rather than coming to be, this fragment emphasizes perishing, which is said to be a way in which ‘what must be’ or necessity (χρεών) applies its law in accordance with the ‘ordering of time’ (χρόνου τάξιν).Footnote ⁸⁷ Yet, while these time intervals seem to apply only to things that are, Ps.-Plutarch before his cosmological passage explicitly claims of Anaximander the following:

This brings to the fore the temporal dimension and its depth. First to be mentioned is the perishing, but each and every ending must be preceded by a beginning. What is important here, however, is that the texts suggest the idea of repetition and thus also the regularity of cycles of coming to be and perishing. Key to its understanding is the interpretation of the ‘infinite time past’, a boundless αἰών. The term αἰών can have a number of meanings, including ‘life’, ‘age’ or ‘eternity’.Footnote ⁸⁹ It can express a lifetime or denote a certain period of time, but what may be crucial here is its explicit qualification as infinite, boundless. It is as if all other lesser time-cycles, which it establishes and defines, arose from it. Moreover, if we take into account the continuation of Ps.-Plutarch's text, which speaks literally of ‘the everlasting’ (τοῦ ἀϊδίου), one may well suppose that τὸ ἀΐδιον need not be synonymous with τὸ ἄπειρον. Rather, it could be a designation of a concrete period of time, a period when that ‘which is generative’ had separated off:

We could thus interpret Ps.-Plutarch as claiming that coming to be and perishing has been taking place since the beginning of time. Since time before time, all there is comes into being and subsequently perishes in due course. αἰών is thus a true beginning and a measure that determines the duration of life. A boundless αἰών could be interpreted as an infinite time within which all temporal cycles, to which everything is subject, take place. It is not clear whether this could also be applied to the world as such, but if ‘the generative’ separates from ‘the everlasting’, one could assume that a world thus created has a limited duration and is subsequently subject to perishing, just like everything else that exists. The presupposition of infinite time thus opens a possibility of successive infinite worlds.

It remains to be seen, however, whether what is meant is the perishing and subsequent rebirth of a new world or just substantial changes to one world. Although in the case of the Milesians we do not have any direct clues, we might consider Xenophanes, whose philosophy is said to have preserved the basic features of Ionian view of nature. A surviving fragment documents his belief in a cyclical development of worlds:

In the last sentence of this fragment the manuscript uses the term καταβάλλειν, while the Diels–Kranz edition replaces it with the word μεταβολήν, and Kirk, Raven and Schofield use the term καταβολήν. In this, the latter case, the sentence would speak of a ‘foundation’ that ‘happens for all the worlds’. Yet, regardless of these particulars, the main message of this text is clear: it speaks of cyclic changes affecting the whole world. Of special interest for our investigation is the ambiguous use of the plural κόσμοις, which may have been what convinced doxographers, here as well as in Anaximander, that what is meant is a doctrine of infinite worlds. At first glance, one can indeed interpret the passage as referring to individual worlds, which succeed each other, arising again and again after the disasters described in the text. The plural κόσμοις could, however, just refer to the organization of the surface of the Earth, to the distinct areas covered by the sea and the dry land. Alternatively, it could denote parts of our world outside the known settled areas. These are the subject of another text by Xenophanes, where he speaks of ‘regions, sections and zones of the earth’, which have their own Sun and Moon and are ‘a section of the earth not inhabited by us’.Footnote ⁹² A period of floods followed by a renewal would affect not only the known and inhabited world but also these remote regions. If ‘all things were covered with mud’ and ‘the human race became extinct’, then it is clear that such a disaster affected the whole world. What perished, however, was life, not the world as such. Subsequent generations were then again born from mud/earth.Footnote ⁹³ This reading seems to be in agreement with Aetius’ statement that according to Xenophanes the world was ‘ungenerated, eternal and imperishable’.Footnote ⁹⁴

On the other hand, we have seen above that, according to Aristotle, ‘all’ of his predecessors assumed that the world had come into existence at some point. It is therefore possible that the adjectives used to characterize the world of Xenophanes are in fact based on his alleged connection with Parmenides and reflect the characteristics of a god, in this case applied to the world. Similarly, we could also question the conception of the destruction of the world in Xenophanes' philosophy. We have seen that it seems a matter of interpretation to what extent one reads Hippolytus’ text as referring to the perishing of the world or just substantial changes affecting it. At first sight, Xenophanes’ world does not perish; what is destroyed is only the previous arrangement of its various parts, meaning that the world as such is merely undergoing changes. In this context, Diels–Kranz refer to a passage from Aristotle's Meteorologica which speaks of floods, such as those that happened during the time of Deucalion. Such floods did not affect the whole world, only its parts.Footnote ⁹⁵ On the other hand, we could speculate that, in the course of such profound changes, the world, and humanity with it, could indeed perish and after some time a new world would be established, similar to the previous one. While it would be a new world, distinct from the previous one, it would consist of elements of the earlier world. All worlds thus have the same starting conditions, especially mud and moisture, whose interaction first contributes to their creations only to later lead to their destruction.

While in Anaximander's case we do not know what stage would follow the evaporation of moisture in the world, for Xenophanes we have texts documenting the whole cyclic process. In Anaximander, however, references to infinite worlds and temporal cycles also hint at such a process. It may be significant that the subject of the perishing of the world is unclear in other Ionian thinkers too. The closest we get to it is a reference to ‘world conflagration’ (ἐκπύρωσις), ascribed by various ancient authors to Heraclitus, but here we should join the majority consensus of contemporary scholars in viewing this conception of the end of the world as just a late Stoic addition.

The contrast between mere transformations and the perishing of the world is closely linked to ancient theories of coming to be, perishing and changes. It touches upon a basic issue of interpretation of the mutual transformations of the individual things in the world, which is a subject treated by many surviving fragments of Presocratic writing. One can assume that attribution to the Presocratics of the notion of the gradual change of an element that persists through all the changes is an anachronism based on a Peripatetic concept of substance. It is a consequence of a line of thought based on Parmenides. One can thus assume that, in archaic thought, the coming to be of one thing was not seen as a mere transformation of the previous one but as implying its real destruction. Although according to D.W. Graham we cannot know what the transformation of one into another originally meant, we can assume that the previous thing had undergone such a marked change that it is no longer identical with its original state. Unlike a mere change in a thing, the coming to be of a new one thus implies the perishing, death, of the previous one.Footnote ⁹⁶

Death is an important subject in the thought of Heraclitus. It appears not only in the context of the soul, but also in the context of individual elements, where he speaks of their death quite explicitly:Footnote ⁹⁷

Water coming from the earth, into which it previously perished, is thus a different, new water. If we analogically interpret the mutual transformations of elements as a death of the previous ones, it remains to be seen to what extent this could be generalized and applied to the world as such, that is, whether large-scale changes occurring in the world should be understood as just its transformations or rather its continuous coming to be and perishing. We have already noted that reports about the ideas of Ionian thinkers do not mention anything about the particular way in which a world can end. What we have are rather just unclear indications of various profound changes which might lead to the end of the world. It should be noted, however, that the absence of any description of the end of the world is not necessarily very significant, since with the exception of Anaximander we do not have any detailed descriptions of its coming to be.

If, according to Xenophanes, the earth is gradually dissolved by moisture and changed into mud only to reappear again, it would thus be a different earth than before—and consequently also a different world. What is significant here is the periodic nature of these processes, which is clearly asserted. We have seen that Aristotle distinguishes between three positions on the subject of the continued existence of the world. According to the third view, which Aristotle ascribes to Empedocles and Heraclitus, the world alternately comes to be and perishes. And since Simplicius later places Anaximander and other Milesians with respect to this issue in the same group as Heraclitus,Footnote ⁹⁹ one can assume that Anaximander should also belong to a group of thinkers which included both Anaximenes and Heraclitus, who believed that the world comes to be and perishes ‘at different periods of time’.Footnote ¹⁰⁰ Ionian thought on this subject would thus be characterized by the recurring coming to be and perishing of the world, as indicated by Aristotle.

Although none of the relevant quoted texts mentions Anaximander or Xenophanes, one could perhaps find the notion of ‘periods of time’ in the conceptions they express. The world in the form known to us would perish, but after its demise another, new world would be established, which is different from the previous one. At any point in time, only one world exists, and since the perishing of the world is not permanent, there was no need to pay close attention to its description. Eternal motion, which is ascribed to Anaximander in connection with the coming to be, could then be defined on the basis of all other particular temporal cycles. It thus seems that we can, after all, find in his thoughts one form of infinite worlds, namely successive worlds. Infinite worlds could thus be interpreted as the coming to be and perishing of one world which is then succeeded by another world.

One can, meanwhile, suppose that the notion of successive worlds was based on a general tendency of the Ionian thought which reacted to the commonly observed generation and decline and applied these notions by analogy also to the world as such. If Anaximander described the formation of the world against the background of biological parallels, he may have concluded that the world behaves like all other living beings, that is, that it undergoes transformations only to eventually perish. Everything in the world is sooner or later exhausted. If the world came into being like a living organism, it should also eventually perish, but in the order of generations everything that perishes also makes way for its successor. This is how a continuity has been maintained since time immemorial. It is also a matter of common experience. On the level of the world, this interpretation is supported by the biological background of Anaximander's cosmogony together with the working of a boundless αἰών in the cycles of return of all being. The world thus behaves much like nature, which also maintains itself through the order of generations. After its generation, the world thus could not merely keep on changing, just as it could not definitively perish, since everything that is alive is maintained by the order of generations.

Unlike the boundless, all things that exist and the world as such are subject to changes that lead to their inevitable end. Given the importance of moisture, which is closely connected with cosmology, the duration of any particular world in Anaximander's conception would probably depend on the amount of moisture it contains. This would determine the length of time for which a world exists. Aristotle and Alexander of Aphrodisias perhaps report about fatal changes which take place in a world that is heading toward its end. It perishes in its original form only to reappear after a certain period of time.