Anaxagoras of Clazomenae

1. Introduction

Anaxagoras of Clazomenae (c. 500–428 BCE) is widely regarded as a pivotal figure in early Greek philosophy for combining Ionian natural inquiry with a novel theory of Nous (Mind) as a cosmic cause. Active primarily in fifth‑century Athens, he articulated a distinctive pluralist metaphysics in which the apparent coming‑to‑be and passing‑away of things is explained not by creation or annihilation, but by the rearrangement of infinitely divisible “seeds” within an original mixture.

His most famous doctrine holds that “everything is in everything”: every observable substance contains, in varying proportions, traces of all other kinds of stuffs. To account for the emergence of order from this indefinite and highly compounded state, Anaxagoras posited a separate, pure, and unmixed Mind that initiates a cosmic rotation, setting in motion a process of separation and organization. This introduced into Greek thought one of the earliest explicit notions of an immaterial, intelligent principle governing the cosmos.

Anaxagoras also advanced natural explanations of celestial and meteorological phenomena, arguing, for example, that the sun is a fiery stone and the moon an earthy body that reflects light. These claims, preserved mainly through later authors, are often cited as emblematic of the shift from mythological to rational accounts of nature in classical Greece.

Although his treatise On Nature survives only in fragments, Anaxagoras’ ideas became central reference points for later philosophers. Plato and Aristotle both engaged critically with his conception of Nous and mixture, while subsequent ancient commentators transmitted and interpreted his system. Modern scholarship continues to debate how to understand the relation between Mind and matter in his thought, and how far his explanations should be regarded as proto‑scientific or primarily metaphysical.

2. Life and Historical Context

2.1 Biographical Outline

Ancient testimonies place Anaxagoras’ birth in Clazomenae in Ionia around 500 BCE and his death in Lampsacus around 428 BCE, both dates approximate. Little is reliably known about his early life, but most accounts agree that he left Ionia for Athens sometime after the Persian Wars, perhaps in the 480s or 470s BCE. There he reportedly taught and conversed with leading figures, most notably Pericles, and, in some later traditions, the young Socrates.

His period of greatest activity seems to coincide with the ascendancy of Pericles in mid‑fifth‑century Athens. At some point in the 440s–430s BCE he was prosecuted for impiety, a charge often linked to his naturalistic views about the heavenly bodies. Whether he was formally condemned, fined, or simply withdrew is uncertain, but most sources agree that he spent his final years in Lampsacus, where he was honored after his death.

A simplified timeline illustrates the main phases:

2.2 Historical and Cultural Setting

Anaxagoras lived during a transformative era marked by:

• The aftermath of the Persian Wars and the consolidation of Athenian power.
• The rise of Periclean democracy, with its intense political competition and public litigation.
• The flourishing of intellectual life in Athens, including the arrival of sophists and the expansion of philosophical and scientific inquiry.

Scholars often situate him at a crossroads between the Ionian tradition of natural philosophy and the emerging Athenian culture of public debate and civic religion. His willingness to give physical explanations for eclipses, meteors, and the composition of the sun and moon is seen by many as emblematic of a broader shift from mythic to rational accounts of the cosmos, a shift that also heightened tensions with traditional religious sensibilities.

The political uses of impiety charges in democratic Athens form an important backdrop to his trial and exile, linking his life story to larger questions about the place of philosophical inquiry in the classical polis.

3. Sources and Transmission of His Thought

3.1 The Lost Treatise On Nature

Anaxagoras is known to have written a single work, conventionally titled ** On Nature (Peri physeōs)**. No complete manuscript survives; modern knowledge of his doctrines depends on fragments quoted or paraphrased by later authors and on doxographical reports summarizing his views.

The core fragments, usually labeled B‑fragments following Diels–Kranz, are primarily preserved in Simplicius’ commentaries on Aristotle (6th century CE). Other pieces appear in Plato, Aristotle, Theophrastus (via later compilers), Plutarch, Diogenes Laertius, and assorted scholiasts.

3.2 Types of Evidence

Scholars distinguish several layers of evidence:

Debate continues over which passages count as genuine fragments versus later reconstructions. Some editors adopt a strict approach, limiting fragments to explicit quotations; others include broader testimonia where Anaxagoras’ doctrines are summarized.

3.3 Editorial Traditions and Modern Reconstructions

Modern understanding of Anaxagoras has been shaped by key collections:

• The Diels–Kranz edition (Die Fragmente der Vorsokratiker) provided the standard numbering system.
• Later editors and translators (e.g., Schofield, Kirk–Raven–Schofield, Laks–Most) have reassessed the authenticity, order, and interpretation of the fragments.

Proponents of reconstructive readings attempt to infer the structure of On Nature from the thematic clustering of fragments in Simplicius and parallels with other Presocratic treatises. Others caution that the original organization remains highly speculative, given the fragmentary state and the filtering of Anaxagoras’ thought through Aristotelian and Neoplatonist lenses.

As a result, modern scholarship emphasizes both the richness of the surviving material and the limits imposed by its indirect and polemical transmission.

4. Intellectual Development and Influences

4.1 Ionian Background

Anaxagoras’ origins in Ionia place him in continuity with earlier natural philosophers such as Thales, Anaximander, and Anaximenes. These thinkers sought material principles (archai) and offered non‑mythological accounts of celestial and meteorological phenomena. Many scholars argue that Anaxagoras inherited:

• A commitment to explaining the world in terms of natural processes.
• An interest in cosmology and astronomy, including the structure of the heavens.
• The idea of an indefinite or boundless starting state, reminiscent of Anaximander’s apeiron.

However, unlike these predecessors, he substituted a plurality of seeds and introduced Nous as a distinct ordering principle, leading some interpreters to describe him as both a continuator and a radical innovator within the Ionian line.

4.2 Parmenidean and Pluralist Influences

A majority of scholars see Anaxagoras as responding to Parmenides’ challenge concerning being, change, and non‑being. His denial of genuine coming‑to‑be and perishing, and his insistence that all things are always present in the mixture, are often read as attempts to accommodate Parmenidean strictures while preserving the diversity of the sensible world.

In this respect he is grouped with other pluralists such as Empedocles and the atomists (Leucippus, Democritus). Comparative studies highlight convergences—such as the rejection of absolute generation—and divergences, especially Anaxagoras’ emphasis on infinite divisibility and the role of Mind, rather than mechanical necessity or elemental love and strife.

4.3 Athenian Environment and Cross‑Currents

His long residence in Athens exposed him to a distinctive intellectual and political milieu:

• The growth of rhetoric and sophistic education, which may have sharpened attention to argument, explanation, and public persuasion.
• Debates about piety and the gods, intensified by the city’s evolving democratic institutions and festivals.
• Interactions—whether direct or indirect—with figures such as Pericles, dramatists, and early Socratic circles.

Some modern interpreters propose that this environment encouraged Anaxagoras to articulate a more explicit doctrine of Nous as an intelligent principle, while others see his system as primarily rooted in pre‑Athenian Ionian concerns, with Athens functioning mainly as the venue for its dissemination. The relative weight of these influences remains a subject of ongoing scholarly discussion.

5. Anaxagoras in Athens: Politics, Religion, and Trial

5.1 Integration into Athenian Public Life

In Athens, Anaxagoras became associated in later tradition with Pericles, the leading statesman of the mid‑fifth century BCE. Ancient authors such as Plutarch report that Pericles admired his intellectual rigor and that Anaxagoras influenced Pericles’ disposition toward rational reflection. While the historical details are debated, most scholars accept that Anaxagoras moved within elite circles, which facilitated the dissemination of his natural philosophy among Athenian decision‑makers and cultural figures.

Some sources also link him to Socrates’ youth, though this connection is generally viewed as more symbolic than biographically secure, representing Athens’ image of itself as an intellectual center.

5.2 Religious Tensions

Anaxagoras’ explanations of celestial phenomena challenged traditional religious interpretations. Claims such as that the sun is a fiery stone and that the moon is an earthy body illuminated by the sun were seen by some contemporaries as diminishing the divine status of heavenly bodies. While he did not explicitly deny the existence of gods, his approach exemplified natural philosophy (physiologia), which often reframed or displaced mythic explanations.

Ancient testimonies suggest that these ideas provoked suspicion and were later remembered as archetypal cases of intellectual impiety. Modern scholars debate whether popular hostility was widespread or whether such tensions were primarily instrumentalized in elite political struggles.

5.3 The Trial for Impiety

The traditional narrative recounts that Anaxagoras was prosecuted for impiety (asebeia) in Athens, with charges tied to his doctrines about the sun, moon, and perhaps meteorological phenomena. The exact date, legal outcome, and political context remain uncertain:

• Some accounts speak of a death sentence from which he was rescued by Pericles.
• Others mention a fine and voluntary withdrawal or formal exile.
• A number of modern historians suggest the case might have been part of broader attacks on Pericles’ associates, alongside proceedings against figures like Phidias and Aspasia.

Because the main sources (e.g., Plutarch, Diogenes Laertius) are late and colored by retrospective interpretation, there is no consensus on the precise historical sequence. Nonetheless, the episode is widely cited as illustrating how philosophical naturalism could become entangled in Athenian political and religious conflicts, and how charges of impiety could be wielded as strategic tools within democratic litigation.

6. Major Work: On Nature

6.1 Title, Form, and Audience

Anaxagoras’ single known work, conventionally titled ** On Nature (Peri physeōs)**, appears to have been a prose treatise typical of late Presocratic natural philosophy. Ancient testimonies suggest it circulated in Athens and beyond, reaching readers such as Socrates (per Plato) and forming a reference point for Aristotle and later commentators.

Whether On Nature was intended primarily for a specialist philosophical audience or for a broader educated public is debated. Some interpreters emphasize its technical character; others, given its reported impact on figures like Pericles and Socrates, infer that it was at least partially accessible to non‑specialists.

6.2 Content and Probable Structure

Because the work survives only in fragments, its original organization can only be reconstructed hypothetically. Many scholars, drawing on the order in which Simplicius quotes Anaxagoras and on parallels with other Presocratics, propose a rough division:

Not all scholars accept this sequence; some caution that Simplicius’ arrangement reflects his own commentarial agenda rather than the original composition.

6.3 Style and Philosophical Aims

The fragments indicate a concise, assertoric style, with few explicit arguments but frequent programmatic statements. Anaxagoras appears to aim at:

• Providing a unified account of both fundamental metaphysics and observable natural processes.
• Reconciling permanent being with observable change via his theory of mixture and seeds.
• Explaining a wide range of phenomena—cosmic, celestial, meteorological, and biological—within a single conceptual framework centered on mixture and Nous.

Ancient reports that Socrates was initially enthused, then disappointed, by the book (Plato, Phaedo 97b–99c) have shaped later assessments: some view it as a bold but incomplete attempt at a rational cosmology, while others emphasize its innovative yet schematic character.

7. Core Philosophy and System Overview

7.1 Fundamental Commitments

Anaxagoras’ system rests on several interconnected theses:

• Ontological permanence: Nothing genuinely comes into being or perishes; change is understood as composition and separation of pre‑existing constituents.
• Infinite plurality and divisibility: Reality consists of infinitely many qualitatively distinct “seeds”, each of which is infinitely divisible.
• Mixture as the primordial state: Initially, “all things were together” in a dense, highly compounded mixture, without distinct colors or forms.
• “Everything in everything”: Every portion of matter contains at least some share of every kind of seed, though in different proportions.
• Nous as a distinct principle: A pure, unmixed Mind initiates cosmic motion and orders the mixture.

These commitments allow him to maintain both continuity with Parmenidean strictures against non‑being and a pluralistic explanation of the world’s diversity.

7.2 From Mixture to Ordered Cosmos

In Anaxagoras’ account, the primordial mixture is set into motion by Nous, which begins a vortex‑like rotation. This rotation gradually separates constituents:

• Lighter and finer materials move outward, forming aether and heavenly bodies.
• Heavier and denser materials congregate, forming earth and terrestrial structures.

This process is progressive rather than complete; Anaxagoras insists that separation never becomes total, preserving the principle that every region still contains all kinds of seeds, though some predominate.

7.3 Explaining Change and Qualities

On this view, apparent generation (e.g., of flesh from food) is reinterpreted as rearrangement: food already contains seeds of flesh, bone, hair, and so on; nourishment simply allows like seeds to congregate. Similarly, qualitative changes—such as heating, cooling, or color transformations—reflect shifts in proportions of underlying seeds.

Later commentators describe stuffs like flesh or gold as homoeomeries (like‑parted entities), whose parts are of the same kind as the whole. Anaxagoras himself speaks instead of “things” and “seeds,” but the idea is that identifiable substances arise where particular kinds of seeds predominate within an ever‑mixed medium.

7.4 Role of Nous in the System

While Nous is best known as the initiator of cosmic motion, Anaxagoras also describes it as knowing and controlling “all things that have life” in some fashion. Interpreters differ on whether this implies a broadly teleological or merely efficient causation, an issue treated in detail by later ancient critics. In any case, the system as a whole combines:

• A material pluralism grounded in mixture and seeds;
• With a distinct, intelligent principle responsible for the ordered structure of the cosmos.

8. Metaphysics of Mixture and Seeds

8.1 The Primordial Mixture

Anaxagoras begins from the claim that originally:

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“All things were together, infinite both in number and in smallness; and when all things were together, not even any color was apparent, for the mixture of all things prevented it.”

— Anaxagoras, fragment B1 (via Simplicius, Physics commentary)

This mixture (mixis) is characterized by:

• Indefinite complexity: an infinite variety of constituents.
• Homogeneity of appearance: no distinct qualities observable due to total blending.
• Absence of void: many scholars infer that there is no empty space separating constituents.

Some interpreters view this as a physical picture of a dense primordial state; others read it more as a metaphysical assertion about the co‑presence of all kinds in every region of matter.

8.2 Seeds and Qualitative Plurality

The basic constituents, often called “seeds” (spermata), are qualitatively distinct. Later terminology (especially Aristotle’s homoeomeries) groups seeds into kinds corresponding to stuffs like flesh, bone, earth, gold, and so on. The seeds are:

• Eternal and indestructible.
• Infinitely divisible—there is no smallest part.
• Qualitatively determinate—each seed is what it is (bone‑like, flesh‑like, etc.) independently of perception.

Anaxagoras’ doctrine that “in everything there is a portion of everything” (B11) means that no macroscopic object is purely one kind of seed; even a piece of bone contains, in extremely small amounts, seeds of other stuffs.

8.3 “Everything in Everything” and Infinite Divisibility

The principle panta en panti addresses several problems at once:

Some commentators interpret this as an early anticipation of continuum theories, emphasizing the absence of minimal particles. Others stress its Parmenidean motivation, designed to avoid invoking non‑being when explaining change.

8.4 Mixture, Predominance, and Identity

A central metaphysical idea is predominance: a substance is what it is because certain seeds predominate in it, even though all others are present. Thus:

• Flesh is a region where flesh‑seeds outnumber or outweigh others.
• Gold is where gold‑seeds predominate, and so on.

Scholars debate how to understand predominance—quantitatively (by mass, volume, or number) or qualitatively (by causal efficacy). There is also discussion over whether seeds are microscopic objects or more abstract constituent principles. Proponents of a more physical reading see Anaxagoras as offering an early theory of material composition; others emphasize the logical and explanatory role of seeds in accounting for persistence and change under Parmenidean constraints.

9. Nous (Mind) as Cosmic Cause

9.1 Character of Nous

Anaxagoras’ most distinctive innovation is his concept of Nous:

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“Mind is infinite and self‑ruling, and it has been mixed with no thing, but is alone itself by itself.”

— Anaxagoras, fragment B12 (via Simplicius, Physics commentary)

He attributes to Nous several key features:

• Purity and unmixedness: unlike seeds, it is not mixed with anything else.
• Autonomy: it is “self‑ruling” (autokrates), not determined by other things.
• Cognitive power: it “knows all things that are mixed together and separated apart” (B12–13).
• Causal efficacy: it initiates motion and governs the process of cosmic separation.

These properties distinguish Nous from all material constituents, introducing a form of metaphysical dualism between mind and matter.

9.2 Nous and the Origin of Motion

According to fragment B13:

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“Mind, having power over the whole revolution, began to make it revolve from the beginning. First it set in motion that mass which was mixed together and separated off.”

Here Nous functions as the first cause of motion, starting a vortex‑like rotation in the primordial mixture. This motion drives the gradual segregation of lighter and heavier constituents and underpins the entire cosmological development of the world.

Interpreters debate whether Nous acts once and for all at the beginning or continues to operate throughout cosmic history. Some infer from Anaxagoras’ remarks that Mind remains present wherever there is life and order, suggesting ongoing involvement; others emphasize the initial impulse and see later processes as largely determined by the nature of the mixture and the mechanics of rotation.

9.3 Teleology or Mere Efficiency?

A central question is whether Anaxagoras’ Nous is teleological—ordering things “for the best”—or merely an efficient cause of motion. Ancient and modern views diverge:

Many contemporary scholars adopt intermediate positions, suggesting that Anaxagoras introduced intelligence as a causal factor without fully articulating a theory of ends or purposes, leaving later thinkers (especially Plato and Aristotle) to develop explicit teleology.

9.4 Presence of Nous in Living Beings

Anaxagoras also states that while everything except Nous is mixed with everything, “there are some things in which Mind too is present” (B11). Ancient interpreters commonly identify these as living beings, and some infer an early theory in which human cognition partakes of the cosmic Nous.

Debate continues over how literally this participation should be understood:

• Some read it as a shared substance: human minds are locally present manifestations of the same universal Nous.
• Others view it as an analogy explaining how rational order in organisms reflects the broader intelligible structure of the cosmos.

In either case, the doctrine links cosmic causation and psychology, making Nous central not only to cosmology but also to Anaxagoras’ understanding of life and cognition.

10. Cosmology and Astronomy

10.1 Structure of the Cosmos

Building on his theory of mixture and Nous, Anaxagoras presents a layered cosmology. The initial cosmic rotation causes:

• Finer, lighter constituents to move outward, forming aether and the upper regions.
• Heavier, denser constituents to gather at the center, producing earth.

The universe is thus conceived as a rotating system with concentric regions, differentiated by density and composition. However, because complete separation never occurs, every region still contains traces of all seeds.

10.2 Heavenly Bodies

Anaxagoras offers naturalistic accounts of the sun, moon, and stars that diverge from traditional religious conceptions:

He also reportedly held that the moon has mountains and ravines, implying a surface similar in some respects to earth’s. These claims are preserved mainly through Aristotle and later doxographers and are often cited as early examples of physical astronomy.

10.3 Eclipses, Meteors, and Other Phenomena

Anaxagoras explained eclipses as the interposition of one body between another and the observer:

• Solar eclipses occur when the moon passes in front of the sun.
• Lunar eclipses result when the earth blocks sunlight from reaching the moon.

He interpreted meteors—notably a large meteorite that reportedly fell at Aegospotami—as stones torn from heavenly bodies or the aether and drawn to earth. Winds, clouds, thunder, lightning, and rainbows were likewise given mechanical or physical explanations, often in terms of the interaction of hot and cold, rare and dense.

10.4 Relation to Contemporary Thought

Anaxagoras’ cosmology and astronomy are frequently compared to those of earlier and later Greeks:

• Relative to earlier Ionian thinkers, his accounts are more systematically tied to a general theory of mixture and cosmic rotation.
• Later critics, especially Aristotle, sometimes fault him for lack of precision or for invoking Nous without detailed mechanical accounts of specific motions.

Modern scholars differ on how close his views come to scientific explanation in a modern sense. Some emphasize the observational basis and predictive potential of his eclipse theory; others stress the speculative nature of his claims and their dependence on broader metaphysical assumptions about mixture, density, and motion. In any case, his work marks a significant step toward treating the heavens as subject to the same rational principles as the terrestrial world.

11. Epistemology and Method of Inquiry

11.1 The Status of Perception

Anaxagoras’ explicit remarks on knowledge are sparse, but several themes can be extracted from fragments and testimonies. He is often credited with a nuanced view of perception:

• Perception provides access to appearances, which must be interpreted with care.
• The underlying reality consists of infinitesimal seeds and mixtures not directly visible.

Some later reports attribute to him the dictum that “appearances are a glimpse of the unseen”, suggesting that perceptual data need to be supplemented by reasoned theory to reveal the true structure of things.

11.2 Explaining Beyond Appearances

His theory that “everything is in everything” implies that many genuine constituents are present in quantities too small to be detected. This leads to an implicit reliance on inference:

• From observable changes (e.g., growth from food), he infers the presence of corresponding seeds in what is eaten.
• From celestial phenomena (e.g., phases and eclipses), he infers the shapes, compositions, and motions of heavenly bodies.

This method combines empirical observation with theoretical reasoning grounded in his metaphysical commitments. Some scholars see in this a precursor to scientific theorizing; others emphasize its dependence on a priori principles such as the impossibility of generation from nothing.

11.3 Limits of Human Knowledge

There are indications that Anaxagoras recognized limits to human cognition. Ancient sources attribute to him reflections on the smallness and remoteness of things, which make exact knowledge difficult or impossible. The infinite divisibility of seeds, in particular, implies that the full detail of mixture and composition cannot be directly apprehended.

Rather than abandoning inquiry, however, his approach appears to accept that knowledge will be approximate and inferential, relying on what can be gleaned from the interaction of sense and mind. The presence of Nous in living beings, especially humans, is sometimes interpreted as providing a link between finite cognition and the cosmic intelligence that truly knows all things, though the fragments leave the nature of this relationship underdetermined.

11.4 Method in Natural Philosophy

In practice, Anaxagoras’ method in natural philosophy combines:

• General principles (no coming‑to‑be from nothing; everything in everything; infinite divisibility).
• Qualitative reasoning about density, heat, and motion.
• Analogical arguments, for example from small‑scale separation processes (e.g., spinning or vortex motions) to large‑scale cosmology.

Later critics, particularly Aristotle, sometimes fault him for using broad principles without detailed demonstrations. Contemporary scholars are divided between viewing his method as proto‑scientific and seeing it mainly as a metaphysical framework within which empirical observations are interpreted.

12. Ethical and Religious Implications

12.1 Implications for Traditional Religion

Although Anaxagoras does not appear to have written a systematic theology, his naturalistic explanations of sun, moon, and meteorological events had clear religious implications in the Greek context:

• Heavenly bodies traditionally regarded as divine were reinterpreted as fiery or earthy masses behaving according to natural laws.
• Phenomena often taken as portents or signs from the gods were explained mechanistically.

Critics in antiquity saw such explanations as undermining traditional piety, contributing to the impiety charges brought against him. Defenders, ancient and modern, have suggested that Anaxagoras may have conceived Nous itself as a kind of divine intelligence, compatible with a more philosophical conception of deity, though explicit statements are scarce.

12.2 Human Life and the Role of Mind

Anaxagoras reportedly remarked that humans are distinguished by having Mind (Nous) to the highest degree. Later anecdotes credit him with saying that he lived to contemplate the heavens or to study the sun and moon, presenting philosophical contemplation as a central human aim. While such stories are difficult to verify, they suggest that ancient readers inferred an ethical orientation from his emphasis on Nous:

• Human excellence might be linked to the exercise of intelligence and understanding of nature.
• The presence of Nous in living beings could imply that aligning one’s life with rational order has a distinctive value.

There is little direct evidence of ethical precepts or prescriptions in the surviving fragments, so reconstructions often rely on biographical traditions and the extrapolation of ethical significance from his metaphysics.

12.3 Attitudes toward Fate and Providence

The status of fate or providence in Anaxagoras’ system is debated. Possibilities discussed in scholarship include:

Ancient critics, especially Plato’s Socrates in the Phaedo, famously complain that Anaxagoras failed to develop the ethical and teleological implications of Nous, using it instead as a primarily mechanical explainer of cosmic motion. This has influenced much later interpretation, with some readers seeing unrealized ethical potential in his concept of Mind and others maintaining that ethical and religious concerns remain peripheral in his surviving thought.

13. Reception in Plato and Aristotle

13.1 Plato’s Engagement

Plato refers to Anaxagoras in several dialogues, most notably in the ** Phaedo (96a–99c)**, where Socrates recounts his youthful enthusiasm upon hearing that Anaxagoras posited Mind as the cause of all things. Socrates expected an explanation of the world “for the best,” but reports disappointment when Anaxagoras instead explains things in terms of air, aether, water, and other physical factors.

Plato’s portrayal has been influential:

• It praises Anaxagoras for introducing Nous as a principle distinct from matter.
• It criticizes him for not fully exploiting this principle to provide a teleological account.

In other dialogues (e.g., Apology 26d, Laws 967b–c), Anaxagoras is associated with naturalistic explanations that challenge traditional views of the gods, reinforcing his image as a transitional figure between mythic and rational accounts.

Some scholars argue that Plato’s own development of teleological cosmology in the Timaeus can be read as a response to what he saw as the unfulfilled promise of Anaxagoras’ Nous.

13.2 Aristotle’s Critiques and Appropriations

Aristotle engages extensively with Anaxagoras across several works, including Physics, Metaphysics, and On the Heavens. His reception is multifaceted:

• In metaphysics, Aristotle groups Anaxagoras with other pluralists and credits him with denying absolute generation and destruction. He regards the doctrine of homoeomeries (Aristotle’s term) as a significant attempt to explain substance and change.
• Regarding Nous, Aristotle calls Anaxagoras “like a sober man among the random talkers” for positing an intelligent cause, but he also contends that Anaxagoras uses Mind sparingly, “as a deus ex machina,” turning to it mainly when he cannot account for phenomena otherwise.
• In natural philosophy, Aristotle frequently revisits Anaxagoras’ views on celestial bodies, meteorology, and biology, sometimes preserving valuable details, sometimes recasting them to serve his own argumentative purposes.

Aristotle’s assessments shaped later perception in two main ways:

13.3 Later Ancient Reception via Plato and Aristotle

Because both Plato and Aristotle used Anaxagoras as a foil for their own developments, later philosophers and commentators (Stoics, Middle Platonists, Neoplatonists) often encountered him through their interpretations. Simplicius, for example, preserves long extracts of Anaxagoras’ fragments while commenting on Aristotle, explicitly framing Anaxagoras’ ideas within Aristotelian categories.

As a result, modern scholarship must carefully distinguish between Anaxagoras’ own doctrines and the ways they are refracted through Platonic and Aristotelian critiques. Debates continue over whether Plato and Aristotle fairly represent his intentions, especially regarding the teleological potential of Nous and the systematic coherence of his metaphysics.

14. Comparisons with Other Pre‑Socratics

14.1 Ionian Monists

Compared to early Ionian “monists” like Thales, Anaximander, and Anaximenes, who sought a single archē (water, the indefinite, air), Anaxagoras posits an indefinite plurality of seeds. Key contrasts include:

Some interpreters see Anaxagoras as extending Ionian concerns with natural explanation while abandoning their monistic ambition.

14.2 Parmenides and Eleatic Thought

Anaxagoras shares with Parmenides the denial of genuine coming‑to‑be and perishing, but he rejects Eleatic monism. Where Parmenides posits a single, unchanging Being, Anaxagoras maintains an eternal plurality of seeds whose recombination yields the phenomena of change.

He, like other pluralists, can be seen as mediating between Eleatic arguments about non‑being and the evident diversity of the world, offering a way to reconcile ontological permanence with empirical change.

14.3 Empedocles and the Atomists

Anaxagoras is often compared with Empedocles and with Leucippus and Democritus:

Some scholars emphasize that, unlike Empedocles and the atomists, Anaxagoras denies qualitative change at the fundamental level: seeds retain their nature; only their arrangements and relative predominance alter.

14.4 Other Presocratics and the Sophists

Compared to Heraclitus, Anaxagoras places less emphasis on flux and oppositions, focusing instead on stable constituents within changing mixtures. Relative to early sophists, he shares an interest in argument and explanation, but his surviving work is oriented toward natural philosophy rather than rhetoric or human affairs.

Debates among historians concern how far to group Anaxagoras with other pluralists as part of a single movement, and how far his introduction of Nous and infinite seeds warrants treating him as a distinctive figure whose system cannot easily be assimilated to those of Empedocles or the atomists. Different typologies emphasize either shared responses to Eleatic challenges or the divergent metaphysical strategies that emerged among Presocratic thinkers.

15. Legacy and Historical Significance

15.1 Impact on Ancient Philosophy

Anaxagoras’ introduction of Nous as a distinct, unmixed, intelligent principle and his doctrine of mixture and seeds had enduring effects on subsequent Greek thought:

• Plato and Aristotle took his concept of Mind as a starting point for more elaborate theories of intelligible order and teleology, even while criticizing his execution.
• Later Platonists and Aristotelians revisited Anaxagoras when discussing the nature of divine intellect, the relationship between mind and matter, and the origins of cosmic order.
• Hellenistic schools (Stoics, Epicureans) engaged indirectly with his ideas through debates about determinism, providence, and materialism, often via Aristotelian reports.

Through these channels, Anaxagoras contributed to the long‑term development of central categories in ancient metaphysics, cosmology, and philosophy of mind.

15.2 Role in the History of Science

His naturalistic accounts of eclipses, meteors, and the nature of the sun and moon are frequently cited in histories of science as early examples of rational, law‑like explanations of celestial phenomena. Historians differ on how to characterize this contribution:

Both perspectives agree that his work marks a significant move toward treating the heavens and earth as governed by common natural principles.

15.3 Symbol of Conflict between Philosophy and the Polis

The story of Anaxagoras’ trial for impiety became an emblematic narrative about tensions between intellectual inquiry and civic religion in democratic Athens. Later authors used his case alongside those of Socrates and others to illustrate:

• The vulnerability of philosophers in politically charged environments.
• The potential subversiveness of naturalistic explanations of traditional religious phenomena.

Modern scholarship remains cautious about the historical details but generally acknowledges the symbolic significance of his trial in discussions of free thought in antiquity.

15.4 Modern Interpretations and Ongoing Debates

Contemporary philosophers and historians continue to debate central aspects of Anaxagoras’ legacy:

• The precise nature of Nous: whether it is best understood as a proto‑theological deity, a metaphysical principle, or an abstract explanatory posit.
• The status of his theory as pluralist metaphysics, continuum physics, or both.
• The degree to which he anticipated later dualist views of mind and matter or whether such readings project anachronistic categories onto his thought.

Despite the fragmentary state of the evidence, Anaxagoras is widely regarded as a transitional figure who helped reorient Greek thought toward explanations that combine material plurality with intelligent order, shaping the trajectory of ancient philosophy and influencing conceptions of reason and nature that extend far beyond his own era.