The Misinterpretation of Pre-Socratic Naturalism as Atheism

This study examines the development of early Greek natural philosophy and its relationship to the later emergence of atheistic thought, focusing on the Pre-Socratic thinkers—Thales, Anaximander, Anaximenes, Xenophanes, Heraclitus, and Democritus—and argues that their primary contribution lies not in the rejection of divinity but in a fundamental transformation of explanatory frameworks, namely the shift from mythological, narrative causation grounded in anthropomorphic deities to structural and rational causation based on impersonal principles such as arche, apeiron, logos, and atomic motion. Through an analysis of their doctrines, the study demonstrates that these philosophers consistently pursued ontological unity, explanatory parsimony, and cosmic intelligibility, thereby establishing a coherent and investigable conception of nature. However, it critically challenges the historiographical tendency to label them as ‘atheists,’ identifying this characterization as an anachronistic projection of modern categories onto ancient contexts, since their theories—while diminishing the explanatory role of traditional, man-made mythological gods through abstraction, naturalization, and impersonalization—did not entail an explicit denial of divine existence, but rather reinterpreted divinity in non-anthropomorphic, rational, or immanent terms. The Milesian tradition initiated this trajectory through material monism, Anaximander advanced it through metaphysical abstraction, Xenophanes subjected religious representation to rational critique, Heraclitus reconceived cosmic order through the concept of logos, and atomism, as developed by Leucippus and Democritus, represents its most radical stage by offering a mechanistic cosmology grounded in necessity rather than teleology, yet still not unequivocally atheistic. The study further incorporates Aristotle’s teleological critique of atomism to demonstrate the explanatory limitations of purely mechanistic accounts and to highlight the enduring philosophical tension between necessity and purpose. It ultimately concluded that the Pre-Socratic philosophy inaugurated a form of methodological naturalism that rendered mythological explanations increasingly dispensable and created the intellectual conditions for later atheistic interpretations without itself advocating atheism, thereby underscoring the necessity of avoiding anachronism in the historical and philosophical evaluation of early Greek thought.

Pre-Socratic Naturalism (6th – 4th Century B.C.)

The earliest Greek naturalists (pre-Socratics) occupy the first stage of the Mediterranean story. Their contribution is best described as a transformation in explanatory style: moving from narrative causation (gods act; therefore events happen) to structural causation (nature has principles; therefore events happen). The main contributors in this age were Thales of Miletus, Anaximander, Xenophanes, Heraclitus & Democritus.

Thales and the Ambition of Unity: ‘Arche’, Water, and the Intelligibility of the Cosmos

Thales of Miletus (early 6th century B.C.) occupies a pivotal place in the intellectual history of antiquity as one of the earliest thinkers to articulate a single origin principle (arche) underlying the multiplicity of natural phenomena. ¹ Later testimonies—most prominently from Aristotle—attribute to him the view that water is the fundamental principle of all things. ² While the precise content of Thales’ doctrine is mediated through subsequent philosophical interpretation, his enduring significance lies less in the material choice of ‘water’ and more in the methodological ambition of unity: the claim that diverse phenomena can be explained through transformations of a common substrate.

Sources and Historiographical Considerations

Thales left no extant writings. All attributions derive from later authors, chiefly Aristotle (4th century B.C.), along with doxographical traditions (summarized accounts of earlier views) preserved by writers such as Diogenes Laertius and Simplicius. Aristotle’s Metaphysics identifies Thales as the first to posit a material principle (arche), namely water, as the origin of all things. Aristotle states:

Thales, the founder of this school of philosophy (Ionian School), says the permanent entity is water (which is why he also propounded that the earth floats on water). Presumably he derived this assumption from seeing the nutriment of everything is moist, and that heat itself is generated from moisture and depends upon it for its existence (and that from which a thing is generated is always its first principle). He derived his assumption, then, from this; and also from the fact that the seeds of everything have a moist nature, whereas water is the first principle of the nature of moist things. ³

This claim marks a decisive shift in explanatory orientation. Rather than describing cosmic origins through mythic genealogies of gods, Thales advances a naturalistic principle. Importantly, and logically, this does not imply atheism. Aristotle elsewhere reports that Thales held that ‘all things are full of gods,’ suggesting a worldview in which natural processes may still be infused with animation or divinity. Moreover, Diogenes Laertius states that Thales upheld the independent and eternal pre-existence of God. He is said to have maintained that God is the most ancient of all beings, since He exists without any prior cause, even in terms of generation. Furthermore, Thales is described as affirming that the world is the most beautiful of all entities because it was fashioned by God. ⁴ The innovation, therefore, lies not in the rejection of the sacred but in the relocation of explanation to an intelligible substrate accessible to inquiry. Thales' inquiry into the nature of reality and initial causes could have posed significant challenges to the ancient Greek religion's belief in divine creation. Yet, there is no evidence of any punishment for his work, which shows that his views were not challenged by the religious class of that time.

Themes Found in Thales’ Claims

Thales’ claim boast an ambition of unity which manifests in three interconnected dimensions:

Ontological Unity: Multiplicity is Reducible to a Single Underlying Reality

Thales’ claim that water is the arche—the originating principle of all things—⁵ suggests that the apparent diversity of the world is not ultimate. Instead of multiple independent substances governed by mythic genealogies of gods, Thales proposed that everything ultimately derives from one foundational reality.

This does not mean that everything visibly resembles water; rather, it means that all forms—earth, air, fire, living beings—are transformations or modifications of a single substratum. ⁶ In philosophical terms, this is monism: reality is fundamentally one, not many.

The revolutionary aspect here is not the choice of water, but the move toward unity behind diversity. Nature becomes a coherent system grounded in one explanatory base rather than a collection of unrelated divine actions or accidental formations.

Explanatory Parsimony: Minimal Number of Principles Accounts for Maximal Diversity

Thales’ approach exemplifies what later philosophy recognizes as the principle of parsimony—the preference for the simplest sufficient explanation. Instead of explaining natural phenomena through a plurality of independent divine agents, as was characteristic in traditional mythological thought, he reduced the diversity of the cosmos to a single underlying principle, namely water. This move represents a decisive methodological transformation: explanation is no longer episodic, personified, and tied to the ‘variable will’ of different deities, but unified, impersonal, and conceptually economical. By seeking one foundational substrate capable of accounting for the multiplicity of observable phenomena, Thales implicitly affirms that nature operates as a coherent and intelligible system governed by consistent principles rather than arbitrary interventions. In doing so, he introduces a rational economy of explanation, privileging simplicity, universality, and theoretical unity—an approach that would profoundly shape the subsequent development of early Greek philosophy, particularly among the later Milesian thinkers.

Cosmic Intelligibility: Structured Order discoverable through Reason

Thales’ inquiry presupposes what may be termed cosmic intelligibility—the conviction that the world possesses an underlying order that can be discovered through rational investigation. By positing a single foundational principle (arche), he implicitly rejects the notion of a chaotic or arbitrary cosmos governed by unpredictable forces. Instead, his approach assumes that reality is structured and coherent, such that diverse phenomena can be understood as expressions or transformations of a unified substratum. This marks a profound intellectual transition: whereas mythological thought explains the world through narrative, genealogy, and divine agency, Thales’ mode of inquiry seeks explanation through underlying structure and consistency.

A critical nuance in interpreting Thales is the absence of explicit theological negation. Aristotle’s De Anima recounts that Thales attributed soul even to magnets, given their capacity for motion. ⁷ This suggests a worldview in which nature is animated rather than mechanistically inert. Consequently, the Milesian innovation is methodological rather than metaphysical in a secular sense. The cosmos is not demythologized or de-divinized, so much as rationalized. Explanatory coherence is sought within nature itself, even if divine language persists. This distinction is essential as early Greek cosmology demonstrates that unified natural explanation does not inherently entail atheism. Rather, it presupposes that the world is ordered and thus investigable.

The Legacy of the Milesian Program

Thales’ successors—Anaximander and Anaximenes—retain the commitment to unity while revising the candidate principle. Anaximander’s apeiron ⁸ (the indefinite or boundless) and Anaximenes’ identification of air as the fundamental substance ⁹ reflect continuity of method amid theoretical disagreement. The trajectory illustrates a foundational feature of philosophical inquiry: once the question of arche is posed, competing hypotheses arise within a shared conceptual framework. The debate itself testifies to the establishment of a research program centered upon ontological unity and rational explanation rather than advocating the case for atheism.

Anaximander

Anaximander of Miletus (c. 610–546 B.C.), a successor to Thales radicalized the inquiry by positing the apeiron (‘the boundless’ or ‘the indefinite’) as the origin (arche) of all things. ¹⁰ This move marks a profound abstraction in early philosophy, i.e., the ultimate source of reality is not a visible substance nor a mythic creator, but an impersonal, indefinite, and eternal principle.

The Doctrine of the Apeiron

The Greek term apeiron denotes a phenomenon which is unlimited, indefinite, or boundless. ¹¹ For Anaximander, this principle which is infinite in its power, functions as the origin of all determinate things. ¹² Unlike Thales’ water, the apeiron is not a particular element. It transcends all specific qualities—hot, cold, moist, dry—and thus can generate them without itself being exhausted.

Anaximander posits an originating principle that is infinite and without temporal or spatial limitation, from which all worlds arise and into which they return through a necessary process of succession. This depiction implies a reality that is eternal in itself, even though the individual worlds, it generates, are transient. Although such a principle assumes a role traditionally associated with divinity—namely, as the ultimate source and ground of all existence—it is not presented in anthropomorphic or personal terms. ¹³ It is generative not by will, but by intrinsic structural necessity. This conceptual move deepens the Milesian ambition of unity, i.e., the origin must be sufficiently fundamental to account for all opposites without itself being one of them.

Impersonality and the Rationalization of Cosmology

The conception of the apeiron marks a significant move toward the impersonalization of cosmic explanation. Whereas earlier mythic frameworks—such as those reflected in Hesiodic cosmology—understood the world as emerging through divine genealogies and the actions of anthropomorphic gods, ¹⁴ Anaximander’s account presents a markedly different picture. The originating principle is described as an indefinite and infinite source from which worlds arise and to which they return through a necessary process. Within this framework, cosmic order is not the result of divine deliberation or conflict, but of an impersonal and law-governed process in which opposites emerge, interact, and are reabsorbed in accordance with an overarching principle of necessity and justice. Even if the apeiron is described as ’divine’, it is divine in an abstract and ontological sense, not as a mythic being. This marks a decisive shift from narrative causation to structural causation.

Necessity, Justice and Cosmic Balance

Anaximander’s surviving fragment offers one of the earliest attempts to articulate a rational structure underlying cosmic change, expressed through a strikingly juridical vocabulary:

...ἐξ ὧν δὲ ἡ γένεσίς ἐστι τοῖς οὖσι, καὶ τὴν φθορὰν εἰς ταῦτα γίνεσθαι κατὰ τὸ χρεών• διδόναι γὰρ αὐτὰ δίκην καὶ τίσιν ἀλλήλοις τῆς ἀδικίας κατὰ τὴν τοῦ χρόνου τάξιν. ¹⁵

…Where the source of things is, to that place they must also pass away, according to necessity; for they must pay penance and be judged for their injustices, in accordance with the ordinance of time. ¹⁶

This formulation presents the cosmos not as a product of arbitrary forces, but as a self-regulating order structured by balance and accountability. The language of ‘justice’ and ‘recompense’ metaphorically expresses a principle of equilibrium: opposing forces—such as hot and cold, moist and dry—temporarily assert dominance, yet inevitably surrender that dominance in accordance with an overarching order and balance.

At the center of this process lies necessity. Change is not driven by caprice or external intervention, but unfolds through intrinsic, law-like processes embedded within reality itself. The cosmos operates through an internal logic in which excess is corrected and imbalance resolved.

Time, in this framework, assumes a decisive role as the arbiter of cosmic order. It ensures that every deviation is eventually rectified, that every dominance is transient, and that equilibrium is continually restored.

In this way, the fragment articulates an early vision of a law-governed universe, where regularity, proportion, and balance are not imposed from without, but arise from the very structure of existence itself.

Intellectual Impact on Early Atheistic Trajectories

As per the data provided above, Anaximander does not reject the existence of the gods, nor does he advance an explicitly irreligious position. Yet his cosmology participates in a gradual transformation of the Greek intellectual landscape that would later render atheistic and naturalistic thought conceivable. By explaining origins through an abstract, indefinite principle (apeiron) rather than divine genealogy, he initiates a process of demythologization as the myths were illogical. Natural processes unfold not through personal will but through necessity, and as cosmic order comes to be understood in terms of structural balance, the explanatory role of anthropomorphic deities becomes increasingly marginal. In this sense, Anaximander does not deny divinity; rather, he diminishes its indispensability within rational explanation.

The philosophical significance of this move is considerable. Anaximander’s doctrine marks a decisive advance in metaphysical abstraction. Unity is no longer grounded in a tangible element, but in an indefinite principle capable of generating opposites without itself being exhausted. The cosmos is governed by necessity and equilibrium, and change is understood as an impersonal process regulated by intrinsic order. In extending the project initiated by Thales, Anaximander transforms its scope, shifting from material monism toward a more abstract ontology in which reality is intelligible through structure rather than narrative agency.

Anaximenes (6th Century B.C.)

Anaximenes of Miletus, the third major thinker of the Milesian school, advanced a distinctive form of material monism by identifying air as the arche—the fundamental principle underlying all reality. ¹⁷ Departing from Thales of Miletus and Anaximander, he sought to reconcile determinacy with boundlessness by positing air as both empirically observable and ontologically primary.

Anaximenes explained cosmic diversity through a mechanism of rarefaction and condensation, whereby air becomes fire when thinned and progressively transforms into wind, cloud, water, earth, and stone when condensed. ¹⁸ This constitutes one of the earliest systematic theories of physical change grounded in observable processes rather than mythic agency.

Furthermore, Anaximenes attributed a quasi-vital character to air, associating it with pneuma (breath or life-force), thereby extending his principle from cosmology to anthropology: just as the soul (composed of air) sustains the body, so air encompasses and governs the cosmos. ¹⁹ His doctrine thus represents a crucial phase in early Greek philosophy, combining empirical observation with abstract generalization, and contributing to the transition from mythological cosmologies to rational explanation.

Thus, Anaximenes himself cannot be classified as an atheist in any strict or historically accurate sense. The very structure of his thought—particularly his attribution of life-giving, governing, and all-encompassing qualities to air—retains features traditionally associated with divinity, for in early Greek cosmology the arche is not a lifeless substrate but a principle endowed with quasi-divine status. Indeed, later testimonies indicate that the Milesians regarded their fundamental principle as ‘divine’ insofar as it is eternal, all-pervading, and causally primary. At the same time, Anaximenes indirectly contributes to the intellectual conditions that render later atheistic or naturalistic thought conceivable by explaining cosmic order through impersonal processes such as rarefaction and condensation rather than through the volition or conflict of anthropomorphic deities. However, such atheistic interpretations are not intrinsic to his doctrine but arise from retrospective readings by later thinkers, who extended the naturalistic implications of Milesian cosmology beyond what Anaximenes himself explicitly affirmed. Consequently, any attribution of atheism to him reflects a historiographical projection rather than his original philosophical position.

Xenophanes of Colophon (c. 570–475 B.C.)

Xenophanes was born in Colophon in Ionia and spent much of his life as a wandering poet-philosopher. His surviving fragments, preserved by later writers such as Sextus Empiricus, Clement of Alexandria, and Simplicius, reveal a thinker best remembered for a novel critique of anthropomorphism in religion, a partial advance toward monotheism, and some pioneering reflections on the conditions of knowledge. ²⁰ Unlike the Milesians, whose focus lay primarily in identifying a material arche, Xenophanes turned attention toward the character of divine representation itself. The intellectual climate of the late 6th century B.C. had already witnessed attempts to explain nature through impersonal principles. Xenophanes extends rational scrutiny beyond nature to religious tradition.

Rejection of Homeric and Hesiodic Depictions

Xenophanes directly challenges the moral authority of traditional Greek religion by criticizing the portrayal of gods in the works of Homer and Hesiod. ²¹ In a well-known fragment, he observes that these poets attributed to the gods actions that are morally reprehensible among humans—such as theft, adultery, and deception. ²² This critique is not merely literary but philosophical. It calls into question whether inherited poetic narratives can serve as reliable sources of theological truth. By exposing the ethical inconsistency of mythological depictions, Xenophanes undermines their authority and opens the way for a more rational evaluation of religious belief.

The Argument from Cultural Projection

Xenophanes further deepens his critique by identifying anthropomorphism as a product of cultural projection. He notes that different peoples imagine their gods in their own image—Ethiopians as black and flat-nosed, Thracians as blue-eyed and red-haired—and extends this insight through a striking analogy: if animals could depict gods, they too would fashion them in their own likeness. ²³ This argument represents a significant intellectual shift, suggesting that religious imagery reflects human psychology and cultural context rather than objective divine reality. In doing so, Xenophanes anticipates later critiques of religion that interpret anthropomorphic theology as a projection of human attributes onto the divine.

A Novel Conception of Divinity

In place of anthropomorphic polytheism, Xenophanes proposes a radically different understanding of the divine. He speaks of a single, supreme god who is unlike mortals in both form and thought, thereby rejecting the physical and psychological limitations attributed to the gods of myth. This divine being is characterized by unity, intellectual supremacy, and non-corporeality; it perceives, thinks, and governs in a manner wholly distinct from human experience. ²⁴ Rather than acting through physical intervention or mythic narrative, this god exerts influence through intellect alone. Xenophanes’ conception thus marks a decisive move toward abstraction, transforming divinity from a collection of personalized beings into a unified, philosophical principle.

Xenophanes and the Development of Early Atheism

As can be gauged from the information above, Xenophanes is best understood not as an atheist, but as a reformer of religious thought. His critique targets the distorted, anthropomorphic portrayals of the gods in traditional Greek religion, not the existence of the divine itself. By rejecting morally flawed depictions and affirming a single, supreme reality—unlike humans in form and thought—he seeks to purify theology and align it with rational and ethical coherence. In this sense, his approach resembles that of prophetic traditions, which correct corrupted beliefs and call toward a more authentic understanding of God.

However, the methods he employs—questioning tradition, exposing cultural projection, and subjecting belief to rational scrutiny—had broader intellectual consequences. These tools weakened the unquestioned authority of myth and opened the door for later thinkers, such as the Sophists and Diagoras of Melos, to push such critiques further, sometimes toward explicit irreligion. Thus, the association of his thought with atheism, is not intrinsic to his own doctrine but arises from subsequent interpretations later on that extend his critical method beyond the boundaries he himself maintained. The movement from myth to critique, inaugurated by Xenophanes, represents one of the earliest philosophical examinations of religion as a human cultural phenomenon.

Heraclitus of Ephesus (c. 540–480 B.C.): Logos and Cosmic Order without Mythic Narration

Heraclitus flourished in Ephesus in the late 6th and early 5th centuries B.C. ²⁵ Unlike Thales or Anaximander, his surviving material consists of aphoristic fragments preserved in later authors such as Aristotle, and Sextus Empiricus. ²⁶

Heraclitus of Ephesus represents a decisive moment in the transformation of Greek thought from mythic narration to rational articulation. While earlier Milesian philosophers sought a unifying material principle, Heraclitus advances a more abstract and structural concept: the logos. Frequently translated as ‘reason,’ ‘account,’ ‘measure,’ or ‘law,’ the logos in Heraclitus signifies an intelligible order underlying perpetual change. ²⁷ In a cosmos governed by logos, events unfold according to rational structure ²⁸ rather than divine genealogy or personal intervention. This conceptual shift contributes to the broader rationalization of Greek cosmology and indirectly reshapes the theological landscape. His quotation is mentioned in the book as:

Although all things come to pass in accordance with this account (logos), men are like the untried when they try such words and works as I set forth, distinguishing each according to its nature (physis) and telling how it is. ²⁹

Heraclitus structures his statement carefully to make one main point. He repeats similar wording to show a contrast between two things: the universal truth of the Logos and the failure of human beings to understand it. Everything in the world happens according to this Logos, yet people remain confused and inexperienced in recognizing it.

Although humans constantly experience this order—since it governs all things—they still fail to grasp it, even when Heraclitus explains it clearly. They do not understand either his words or the facts themselves. Heraclitus claims that he simply describes reality as it truly is, explaining each thing according to its nature (physis).

By using terms like physis (nature), historia (inquiry), and kosmos (world order), Heraclitus aligns himself with the emerging rational and scientific tradition of early Greek philosophy, presenting his teaching as a structured explanation of reality rather than myth.

Misconception Regarding Heraclitus’s Theory

Some parts of the fragment of Heraclitus have often been hastily read as a denial of divine agency, and thus presented as an early articulation of atheistic thought. At first glance, the statement appears to reject creation altogether, suggesting a self-sufficient universe that exists independently of any divine will. This surface reading can easily lead to the misconception that Heraclitus is negating the existence of God or advocating a purely materialistic cosmology. One of such quotations is as follows:

The ordering (kosmos), the same for all, no god nor man has made, but it ever was and is and will be: fire ever living, kindled in measures and in measures going out. ³⁰

According to Kahn (2001), this statement is not a denial of God. The confusion arises because later readers interpret kosmos in the technical sense of ‘the world’ whereas Heraclitus initially employs its earlier meaning of order, arrangement, or harmony. In this context, Heraclitus is not denying divinity; rather, he is rejecting the idea that the order of reality is the product of an external craftsman-like agent—whether human or divine—who constructs the world from outside. Instead, he presents the cosmos as eternal (‘ever was and is and will be’) and self-ordering, symbolized by ‘ever-living fire,’ which continuously transforms ‘in measures.’ The commentary further clarifies that Heraclitus is moving away from mythological models of divine creation or genealogy and toward a conception of reality as a natural, self-organizing process (physis). ³¹ The order of the cosmos is not imposed; it is intrinsic. In this sense, the cosmos itself carries divine attributes—eternity, rational structure, and unity—rather than being the product of a separate, anthropomorphic deity.

Shift from Traditional Deities to Logos

Heraclitus of Ephesus occupies a uniquely ambiguous position in the history of early Greek thought. Ancient and modern interpreters have variously classified him as a material monist or process philosopher; a scientific cosmologist or a religious thinker; an empiricist, a rationalist, or even a mystic. ³² This diversity of interpretation reflects the depth and complexity of his fragments rather than any inconsistency in his thought.

What is clear, however, is that Heraclitus does not advocate atheism. On the contrary, he affirms a form of divinity—yet one that is radically reconfigured. His central concept of the Logos represents a universal, rational principle that orders and governs all things. This principle is not a personal deity in the mythological sense, but neither is it a denial of the divine. Rather, it is a transformation of divinity: the divine becomes identical with rational structure, unity, and the intrinsic order of the cosmos.

His critique is directed primarily at the anthropomorphic religion of his time. He ridicules practices such as blood sacrifice and idol worship, not to deny God, but to reject inadequate human representations of the divine. ³³ In this sense, his project is theological reform, not irreligion. The cosmos, for him, is governed by an immanent rational order—often symbolized as ‘ever-living fire’—rather than by arbitrary divine personalities.

This shift has important consequences. By grounding cosmic order in an impersonal rational principle, Heraclitus reduces reliance on manmade mythological explanations. However, the move toward naturalism or atheism is not his own. It is only in later thinkers—such as Leucippus and Democritus—that we find more explicit attempts to explain the world independently of divine agency, while Sophists go further in critiquing religion itself.

Thus, Heraclitus should be understood as a critical reformer of ambiguous religious thought, not an atheist. His rejection of anthropomorphism and his identification of the divine with rational order helped rationalize the Greek worldview, indirectly preparing the ground for later naturalistic and even atheistic developments—though these were developments made by others, not conclusions he himself endorsed.

Leucippus and Democritus: The Maturation of the Atomistic Alternative to Providence{{p

With Leucippus and Democritus’s atomism, early Greek natural philosophy reaches a decisive stage in the articulation of systematic materialism. ³⁸ Whereas the Milesians (Thales, ³⁹ Anaximander ⁴⁰ & Anaximenes ⁴¹) sought unity in a single underlying principle and Heraclitus emphasized rational structure (logos), ⁴² the atomists propose a fully developed ontological framework grounded in indivisible bodies (atoms) and empty space (void). It provides a cosmology that does not require providential design or divine intervention as causal principles. While Democritus does not explicitly deny the existence of gods, atomism introduces a powerful alternative to teleological or providential explanations—an alternative that would later shape debates in ethics, theology, and metaphysics.

The Ontology of Atoms and Void

The atomists Leucippus and Democritus conceived reality as composed of an infinite number of indivisible bodies (atoms) moving in the void. These atoms were understood to be infinite, eternal, ungenerated, and indestructible, since division beyond a certain point was considered impossible; hence they are ‘atoms’ (from atomos, indivisible). They were solid and without internal structure, differing only in shape, size, arrangement, and position, which together account for the diversity of observable phenomena. The atoms themselves possess no qualitative properties such as color, taste, or purpose; such qualities arise only at the level of perception through their configurations. ⁴³ Crucially, since this theory boasts that atoms are eternal, i.e., they were never created and will never be destroyed, it rejected teleology: atoms do not act for an end but move according to necessity, governed by mechanical interactions and motion in the void.

The Void as Necessary Condition

In atomist philosophy, the concept of the void (kenon) is as fundamental as that of atoms themselves. Leucippus and Democritus argued that without empty space, motion would be impossible, since bodies would have no room to move or rearrange. By affirming the reality of the void, they directly opposed the Eleatic tradition, especially Parmenides, who denied the existence of non-being and therefore rejected the possibility of change and motion. The atomists resolved this philosophical impasse by positing a dual ontology: ‘being’ consists of solid, indivisible atoms, while ‘non-being’ consists of the void, which, though empty, is nevertheless real in the sense that it allows for separation, movement, and recombination. ⁴⁴

Atomism presents a cosmology that is fully explainable without reference to divine design or purpose. Leucippus and Democritus held that worlds come into being through the motion, collision, and aggregation of atoms in the void. There is no divine craftsman organizing the cosmos, nor any overarching teleological plan guiding it. Instead, all natural phenomena occur by necessity. In this framework, order is not imposed from outside but emerges from the arrangement of atoms, complexity arises through their combinations, and change results from their continual rearrangement. Thus, within this system, the status of the gods is significantly reduced. Although Democritus does not explicitly deny their existence, his theory alludes that, if gods exist, they too are composed of fine atoms and are part of the natural order. They do not create, govern, or sustain the cosmos, and thus lose any central explanatory role. In effect, divinity is 'naturalized,' and cosmic processes proceed independently of divine intervention.

Aristotle’s Critique of Democritus’s Atomism

The teleological principle that underlies the philosophy of Aristotle is fundamentally directed against the mechanistic atomism of Democritus. Aristotle maintains that natural beings and processes cannot be adequately explained merely through material constituents and motion, but must be understood in terms of final causation and form.⁴⁵ In ‘The Physics’, he explicitly argues that nature operates ‘for the sake of something,’ ⁴⁶ rejecting the idea that order arises from chance combinations of elements. He states:

… ὥστε τί κωλύει οὕτω καὶ τὰ μέρη ἔχειν ἐν τῇ φύσει, οἷον τοὺς ὀδόντας ἐξ ἀνάγκης ἀνατεῖλαι τοὺς μὲν ἐμπροσθίους ὀξεῖς, ἐπιτηδείους πρὸς τὸ διαιρεῖν, τοὺς δὲ γομφίους πλατεῖς καὶ χρησίμους πρὸς τὸ λεαίνειν τὴν τροφήν, ἐπεὶ οὐ τούτου ἕνεκα γενέσθαι, ἀλλὰ συμπεσεῖν• ὁμοίως δὲ καὶ περὶ τῶν ἄλλων μερῶν, ἐν ὅσοις δοκεῖ ὑπάρχειν τὸ ἕνεκά του. ὅπου μὲν οὖν ἅπαντα συνέβη ὥσπερ κἂν εἰ ἕνεκά του ἐγίγνετο, ταῦτα μὲν ἐσώθη ἀπὸ τοῦ αὐτομάτου συστάντα ἐπιτηδείως• ὅσα δὲ μὴ οὕτως, ἀπώλετο καὶ ἀπόλλυται, καθάπερ Ἐμπεδοκλῆς λέγει τὰ βουγενῆ ἀνδρό πρῳρα.ἀδύνατον δὲ τοῦτον ἔχειν τὸν τρόπον. ταῦτα μὲν γὰρ καὶ πάντα τὰ φύσει ἢ αἰεὶ οὕτω γίγνεται ἢ ὡς ἐπὶ τὸ πολύ, τῶν δ' ἀπὸ τύχης καὶ τοῦ αὐτομάτου οὐδέν. οὐ (199a.) γὰρ ἀπὸ τύχης οὐδ' ἀπὸ συμπτώματος δοκεῖ ὕειν πολλάκις τοῦ χειμῶνος, ἀλλ' ἐὰν ὑπὸ κύνα• οὐδὲ καύματα ὑπὸ κύνα, ἀλλ' ἂν χειμῶνος. εἰ οὖν ἢ ἀπὸ συμπτώματος δοκεῖ ἢ ἕνεκά του εἶναι, εἰ μὴ οἷόν τε ταῦτ' εἶναι μήτε ἀπὸ συμπτώματος μήτ' ἀπὸ ταὐτομάτου, ἕνεκά του ἂν εἴη. ἀλλὰ μὴν φύσει γ' ἐστὶ τὰ τοιαῦτα πάντα, ὡς κἂν αὐτοὶ φαῖεν οἱ ταῦτα λέγοντες. ἔστιν ἄρα τὸ ἕνεκά του ἐν τοῖς φύσει γιγνομένοις καὶ οὖσιν. ⁴⁷

… Why then should it not be the same with the parts in nature, e.g. that our teeth should come up of necessity-the front teeth sharp, fitted for tearing, the molars broad and useful for grinding down the food-since they did not arise for this end, but it was merely a coincident result; and so with all other parts in which we suppose that there is purpose? Wherever then all the parts came about just what they would have been if they had come be for an end, such things survived, being organized. Yet it is impossible that this should be the true view. For teeth and all other natural things either invariably or normally come about in a given way; but of not one of the results of chance or spontaneity is this true. We do not ascribe to chance or mere coincidence the frequency of rain in winter, but frequent rain in summer we do; nor heat in the dog-days, but only if we have it in winter. If then, it is agreed that things are either the result of coincidence or for an end, and these cannot be the result of coincidence or spontaneity, it follows that they must be for an end; and that such things are all due to nature even the champions of the theory which is before us would agree. Therefore, action for an end is present in things which come to be and are by nature. ⁴⁸

The force of this teleological critique becomes most evident in Aristotle’s analysis of living organisms. Here, he presents the famous example of teeth: if teeth were formed purely by chance, as atomists might suggest, their consistent suitability for cutting and grinding would be inexplicable. Instead, he argues that such structures exist because of their function, not by coincidence or chance. The same reasoning applies to organs such as the eye, which exists for seeing. These cases demonstrate that natural parts are ordered toward ends, and that their functional coordination cannot be explained by blind necessity or random collision. Consequently, Aristotle rejects the Democritean reduction of nature to atoms and void, arguing instead that formal and final causes are indispensable for explaining why things are as they are.

Furthermore, he insists that any adequate explanation must include not only what something is made of, but what it is for. This position is further deepened in Metaphysics, where Aristotle argues that the essence or form of a thing determines its being, not merely its material composition. ⁴⁹ Thus, against atomism, Aristotle maintains that structure and function cannot be reduced to accidental arrangements of matter.

In sum, Aristotle’s teleological critique exposes the explanatory insufficiency of atomism: while Democritus accounts for the material and kinetic conditions of phenomena, he fails to explain their purposive organization. Aristotle’s response establishes that nature is not a product of chance-driven mechanisms but a structured order in which beings exist and act for determinate ends, thereby integrating causation with intelligibility at both the physical and metaphysical levels.

Contemporary Views on Democritus’s Atomism

According to ‘The Cambridge Companion to Atheism’, Democritus could have developed into an atheist but apparently did not. ⁵⁰ ‘The Cambridge History of Atheism’ states that even his theory of atomism does not reject God, rather it endorses it because physics and astronomy showed ‘how God normally acted’. Natural laws were seen as manifestation of God’s will; they, as the term ‘law’ implied, required a ‘law giver’. ⁵¹ Furthermore, Francis Bacon said:

Nay, even that school which is most accused of atheism doth most demonstrate religion; that is, the school of Leucippus, and Democritus, and Epicurus for it is a thousand times more credible that four mutable elements and one immutable fifth essence, duly and eternally placed, need no God, than that an army of infinite small portions, or seeds unplaced, should have produced this order and beauty without a divine marshal. ⁵²

This quote shows that the philosophers often accused of atheism—like Democritus and others—actually end up supporting belief in God without intending to. He argues that it is much harder to believe that countless tiny particles moving randomly could create the clear order and beauty of the universe than to believe that there is some kind of design behind it. By comparing atoms to an army without a commander, Bacon shows that such organization cannot exist without guidance. So, instead of proving atheism, Democritus’s idea of atoms unintentionally points toward the need for a divine creator, because the order of the world seems too structured to come from chance alone.

The Essence of Pre-Socratic Philosopher’s Work

The results of the pre-Socratic philosophy can be seen in the following figure:

In assessing the contribution of the Pre-Socratic philosophers to the history of atheistic thought, it is essential to avoid anachronism. Thales, Anaximander, Xenophanes, Heraclitus, and Democritus collectively transformed Greek cosmology by introducing impersonal explanatory principles. That is why they were labelled as ‘atheists’ (a term often used for thinkers who challenged traditional religion) in the traditional sense, because they disagreed with the prevalent cosmological and theological theories of that time. Yet it would be historically inaccurate to portray them as advocates of modern scientific atheism.

Their project was neither an explicit denial of divine existence nor a systematic rejection of religious belief. Rather, it was the inauguration of a new explanatory posture toward the cosmos—one that gradually reduced reliance on man-made mythic narration and anthropomorphic divine agency. The distinction is critical for understanding their historical significance.

The Pre-Socratics were not modern atheists, nor were they proponents of scientific secularism. Their thought frequently coexisted with religious vocabulary and speculative metaphysics. Nevertheless, they introduced a transformative intellectual development: the demonstration that the cosmos can be explained through impersonal principles and structural necessity.

This methodological innovation does not negate divinity, but it renders illogical, man-made mythic narration explanatorily optional and at times, unusable. This ground was used by later thinkers as a foundation of Atheism (according to their inference), even though, none of the philosophers advocated for it.

• ¹  Stephen Bullivant & Michael Ruse (2013), The Oxford Handbook of Atheism, Oxford University Press, Oxford, U.K., Pg. 362.
• ²  Thomas Heyd (2014), And Yet She Moves! – The Earth Rests on Water: Thales on the Role of Water in Earth’s Mobility and in Nature’s Transformations, Apeiron, De Gruyter, Berlin, Germany, Vol. 47, Issue: 4, Pg. 486-487.
• ³  Aristotle (N.D.), The Metaphysics: Books I-IX (Translated by Huge Tredennick), William Heinemann Ltd., London, U.K., Pg. 53.
• ⁴  Diogenes Laertius (N.D.), Lives of Eminent Philosophers (Translated by R. D. Hicks), Harvard University Press, Massachusetts, USA, Vol. 1, Pg. 37.
• ⁵  Stephen Bullivant & Michael Ruse (2013), The Oxford Handbook of Atheism, Oxford University Press, Oxford, U.K., Pg. 362.
• ⁶  . S. Kirk, J. E. Raven & M. Schofield (2013), The Pre-Socratic Philosophers, Cambridge University Press, Cambridge, U.K., Pg. 107.
• ⁷  Aristotle (1907), De Anima (Translated by R. D. Hicks), Cambridge at the University Press, Cambridge, U.K., Pg. 17.
• ⁸  Encyclopedia Britannica (Online): https://www.britannica.com/biography/Anaximander: Retrieved: 06-07-2026
• ⁹  Pavel Hobza (2020), Anaximenes’ ἀήρ as Generating Mist and Generated Air, Apeiron, De Gruyter Brill, Berlin, Germany, Vol. 53, Issue: 2, Pg. 97.
• ¹⁰  Internet Encyclopedia of Philosophy (Online): https://iep.utm.edu/anaximander/: Retrieved: 06-07-2026
• ¹¹  G. S. Kirk, J. E. Raven & M. Schofield (2013), The Pre-Socratic Philosophers, Cambridge University Press, Cambridge, U.K., Pg. 123.
• ¹²  Jonathan Barnes (Ed.) (1991), The Complete Works of Aristotle (Revised Oxford Translation), Princeton University Press, New Jersey, USA, Vol. 1, Pg. 347.
• ¹³  Jonathan Barnes (Ed.) (1991), The Complete Works of Aristotle (Revised Oxford Translation), Princeton University Press, New Jersey, USA, Vol. 1, Pg. 347.
• ¹⁴  Hesiod (1953), Theogony (Translated by Norman O. Brown), The Liberal Arts Press Inc., Massachusetts, USA, Pg. 56-58.
• ¹⁵  Anaximander Fragment (Online): https://www.beyng.com/grk/anax1.html: Retrieved: 07-07-2026
• ¹⁶  Friedrich Nietzsche (1998), Philosophy in the Tragic Age of the Greeks (Translated by Marianne Cowan), Regnery Publishing Inc., Washington D.C., USA, Pg. 45.
• ¹⁷  Alfred William Benn (1908), Early Greek Philosophy, Archibald Constable & Co., London, U.K., Pg. 21.
• ¹⁸  Ibid, Pg. 22.
• ¹⁹  Joan Torello (2015), The Mind of the Ancient Physical Philosophers, Journal of Psychology and Clinical Psychiatry, MedCrave Group, Oklahoma, USA, Vol. 4, Issue: 1, Pg. 2.
• ²⁰  Stanford Encyclopedia of Philosophy (Online): https://plato.stanford.edu/entries/xenophanes/: Retrieved: 07-07-2026
• ²¹  Verity Harte & Melissa Lane (Ed.) (2013), Politeia in Greek and Roman Philosophy, Cambridge University Press, Cambridge, U.K., Pg. 294.
• ²²  A. A. Long (Ed.) (1999), Cambridge Companion to Early Greek Philosophy, Cambridge University Press, Cambridge, U.K., Pg. 210.
• ²³  J. H. Lesher (Ed.) (1992), Xenophanes of Colophon: Fragments A Text and Translation with a Commentary, University of Toronto Press, Toronto, Canada, Pg. 96-97.
• ²⁴  Alfred William Benn (1908), Early Greek Philosophy, Archibald Constable & Co., London, U.K., Pg. 46.
• ²⁵  Encyclopedia Britannica (Online): https://www.britannica.com/biography/Heraclitus: Retrieved: 06-07-2026
• ²⁶  Leonardo Taran (1986), The First Fragment of Heraclitus, Illinois Classical Studies, Scholar’s Press, New York, USA, Vol. 11, Issue 1 & 2, Pg. 2.
• ²⁷  G. S. Kirk & J. E. Raven (1960), The Pre-Socratic Philosophers, Cambridge at the University Press, Cambridge, U.K., Pg. 188.
• ²⁸  Charles H. Kahn (2001), The Art and Thought of Heraclitus, Cambridge University Press, Cambridge, U.K., Pg. 105.
• ²⁹  Ibid, Pg. 98.
• ³⁰  Ibid, Pg. 132.
• ³¹  Ibid, Pg. 132-134.
• ³²  Stanford Encyclopedia of Philosophy (Online): https://plato.stanford.edu/entries/heraclitu s/#Ont: 08-07-2026
• ³³  Nicolas Elias Leon Ruiz (2007), Heraclitus and the Work of Awakening, Stony Brook Theses and Dissertations Collection, New York, USA, Pg. XXXI.
• ³⁴  Patricia Curd & Daniel W. Graham (Ed.) (2008), The Oxford Handbook to Pre-Socratic Philosophy, Oxford University Press, Oxford, U.K., Pg. 333.
• ³⁵  G. S. Kirk, J. E. Raven & M. Schofield (2013), The Pre-Socratic Philosophers, Cambridge University Press, Cambridge, U.K., Pg. 432.
• ³⁶  G. B. Kerferd (1981), The Sophistic Movement, Cambridge University Press, Cambridge, U.K., Pg. 1.
• ³⁷  Patricia Curd & Daniel W. Graham (Ed.) (2008), The Oxford Handbook to Pre-Socratic Philosophy, Oxford University Press, Oxford, U.K., Pg. 17.
• ³⁸  G. S. Kirk, J. E. Raven & M. Schofield (2013), The Pre-Socratic, Cambridge University Press, Cambridge, U.K., Pg. 455-456.
• ³⁹  Aristotle (N.D.), The Metaphysics: Books I-IX (Translated by Huge Tredennick), William Heinemann Ltd., London, U.K., Pg. 52.
• ⁴⁰  Internet Encyclopedia of Philosophy (Online): https://iep.utm.edu/anaximander/: Retrieved: 08-07-2026
• ⁴¹  Alfred William Benn (1908), Early Greek Philosophy, Archibald Constable & Co., London, U.K., Pg. 21.
• ⁴²  G. S. Kirk & J. E. Raven (1960), The Pre-Socratic Philosophers, Cambridge at the University Press, Cambridge, U.K., Pg. 188.
• ⁴³  Richard D. Mckirahan (2010), Philosophy Before Socrates, Hackett Publishing Company, Inc., Indiana, USA, Pg. 395-398.
• ⁴⁴  Stanford Encyclopedia of Philosophy (Online): https://plato.stanford.edu/archives/fall202 5/entries/democritus/: Retrieved: 07-07-2026
• ⁴⁵  Aristotle (N.D.), The Metaphysics: Books I-IX (Translated by Huge Tredennick), William Heinemann Ltd., London, U.K., Pg. 85.
• ⁴⁶  Aristotle (1963), The Physics (Translated by Philip H. Wicksteed & Francis M. Cornford), Harvard University Press, London, U.K., Vol. 1, Pg. 123.
• ⁴⁷  Ibid, Pg. 170.
• ⁴⁸  The Logic Museum (Online): https://www.logicmuseum.com/wiki/Authors/Aristotle/phy sics/liber2: Retrieved: 07-07-2026
• ⁴⁹  Aristotle (N.D.), The Metaphysics: Books I-IX (Translated by Huge Tredennick), William Heinemann Ltd., London, U.K., Pg. 335.
• ⁵⁰  Michael Martin (2007), The Cambridge Companion to Atheism, Cambridge University Press, Cambridge, U.K., Pg. 12.
• ⁵¹  Stephen Bullivant & Michael Ruse (2021), The Cambridge History of Atheism, Cambridge University Press, Cambridge, U.K., Pg. 367.
• ⁵²  W. Aldis Wright (Ed.) (1892), Bacon’s Essays and Colors of Good and Evil, Macmillan & Co., London, U.K., Pg. 64-65.