Ancient Philosophy

Can we know anything? Skepticism is the current that takes this question seriously — and, in its most radical versions, answers no, or at least that we have no way of knowing. More than an attitude of casual doubt, it is a position (and, in antiquity, a way of life) that became the great engine of epistemology: much of the theory of knowledge was born of the attempt to answer the skeptical challenge. This article surveys its ancient and modern forms and the main responses it has received. ...

With Plotinus (c. 204/5–270 CE), Neoplatonism gave ancient philosophy its last great synthesis: the ineffable One, from which all things emanate and to which all things return. But the story did not end there. In the following generations, disciples and successors transformed that vision into an ever vaster and more articulated system — and, at the same time, one ever more bound to religion and ritual. This late Neoplatonism, from Porphyry to Proclus, was the form in which Platonism reached the Latin, Arabic, and Byzantine Middle Ages. This article traces its three great names. (For the starting point, see the article on Plotinus and the emanation of the One.) ...

Probably no philosophical text, in twenty-five centuries of Western tradition, has been more commented, paraphrased, glossed, and reinterpreted than the passage that opens Book VII of Plato’s Republic. In three pages of translation, Socrates asks Glaucon to imagine men chained from birth at the bottom of a cave, seeing only shadows projected on a wall — and proposes that this scene describes, with startling fidelity, the common condition of human beings. This is the Allegory of the Cave, and it is at once one of the most famous pieces of philosophy and one of the most systematically misunderstood. To read it rigorously, it must be situated in its context: it is the third of three articulated images — following the metaphor of the sun and the divided line — that constitute the core of Plato’s mature thought. ...

At the turn of the third century CE, when the philosophical schools of Antiquity seemed to have exhausted their possibilities, a thinker born in Roman Egypt undertook the most ambitious metaphysical synthesis the ancient world had ever seen. Plotinus (c. 205–270 CE) did more than comment on Plato: he transformed Platonism into a complete ontological architecture centered on the idea that all of reality emanates from an absolute principle — the One — and that the destiny of the human soul is to return to that primordial unity. ...

Imagine a world where everything that happens — a storm, a failed harvest, a child being born — is explained by the will of some god. For millennia, humanity lived within this mythical vision of the cosmos. Then, around the 6th century BC, in a small coastal city of Asia Minor called Miletus, something extraordinary happened: a group of thinkers decided to ask why without appealing to the gods. This shift — from mythos to logos, from myth to reason — is one of the most decisive moments in human intellectual history. The men who played a leading role in this transformation are called pre-Socratics: the philosophers who preceded Socrates and founded, with their bold questions, the Western philosophical tradition. ...

Anaxagoras Born in Clazomenae, in Ionia, around 500 BCE, Anaxagoras was the first philosopher to bring the Ionian tradition to Athens, where he lived for some thirty years and became a friend and adviser of the statesman Pericles. His intellectual boldness cost him dearly: accused of impiety for holding that the Sun was not a god but an incandescent stone, he was put on trial and had to leave the city, taking refuge in Lampsacus. ...

Anaximander A fellow citizen and disciple of Thales of Miletus, Anaximander (c. 610–546 BCE) was one of the boldest minds of the Milesian school and perhaps the first thinker to write a prose treatise on nature. Tradition credits him with the pioneering use of the term arché (“principle”), as well as remarkable achievements: drawing the first map of the inhabited world and introducing the gnomon (sundial) into Greece. Dissatisfied with Thales’s water, Anaximander proposed as the principle the apeiron — the boundless, indeterminate, and imperishable. No particular element could give rise to all the others without being consumed by them; only something indefinite and inexhaustible could be the eternal source of everything. From the apeiron, eternal and divine, the opposites (hot and cold, wet and dry) separate out, and from this separation worlds are born — which, in due time, return to it. The only surviving verbatim fragment, transmitted by Simplicius, speaks of this cosmology in moral terms: things “pay one another penalty and retribution for their injustice, according to the order of time.” ...

Anaxímenes The third great name of the Milesian school, Anaximenes (c. 585–525 BCE) was a disciple of Anaximander. At first glance he took a step back, rejecting his master’s indeterminate apeiron and returning to a concrete element as the principle: air (aēr). But his choice carried a decisive advantage — air, being determinate, allowed him to explain how the single principle transforms into all things, something that neither Thales’s water nor the apeiron explained clearly. ...

Aristotle Born in Stagira, in Macedonia, around 384 BCE, the son of Nicomachus — physician to the Macedonian court — Aristotle entered Plato’s Academy at the age of seventeen, where he remained for some twenty years, until his master’s death. He later tutored Alexander the Great and, in 335 BCE, founded the Lyceum in Athens, a school whose members became known as Peripatetics (from their habit of discussing while walking). With Alexander’s death and the wave of anti-Macedonian feeling, he left Athens in 323 BCE — so that the city, according to ancient tradition, “might not sin twice against philosophy” — and died the following year in Chalcis. The body of texts we have inherited from him is the largest and most systematic of antiquity, spanning logic, physics, biology, psychology, metaphysics, ethics, politics, rhetoric, and poetics. ...

Carneades of Cyrene Carneades of Cyrene (c. 214/213–129/128 BC) was the most prominent head (scholarch) of the New Academy in Athens and the central figure of Academic Skepticism. Born in Cyrene in North Africa, he emigrated to Athens and remained there for his entire philosophical career, leading an Academy that had taken a radically skeptical turn since Arcesilaus. Carneades left no writings — an apparently deliberate choice consistent with his position that no thesis should be held dogmatically. His thought reaches us primarily through three mediations: his disciple Clitomachus of Carthage, who recorded his lectures in more than four hundred books; Cicero, who in the Academica and De Natura Deorum presents and debates Academic positions; and Sextus Empiricus, who preserved several of his arguments against the Stoics. ...

Confucius (Chinese: Kǒngzǐ 孔子, “Master Kong”; Jesuit Latinisation: Confucius) was born in the state of Lu (present-day Shandong province, China) in 551 BCE and died in 479 BCE. He was a teacher, public official, and moral reformer who, after a life of frustrated political efforts, devoted himself to teaching and to the study of the ancient Chinese classics. His thought is known principally through the Lunyu (Analects 論語), a compilation of sayings and dialogues made by his disciples and the later tradition — the historicity of individual passages is a matter of debate among specialists. ...

Democritus Born in Abdera, in Thrace, and active around 430 BCE, Democritus was one of the most erudite minds of antiquity — he traveled widely and wrote on almost everything, though none of his works has reached us. Tradition nicknamed him “the laughing philosopher,” in contrast to the melancholy Heraclitus. Together with his teacher Leucippus, he is the founder of atomism, the first fully materialist and mechanistic philosophy in history. His thesis is as simple as it is audacious: reality reduces to two principles — atoms and the void. Atoms (from the Greek atomon, “indivisible”) are eternal, solid, imperceptible particles that differ only in shape, size, position, and arrangement. The void is the space in which they move. Everything that exists — things, the world, and even the soul (made of finer, subtler atoms) — results from the collisions and combinations of these atoms in eternal motion. In Democritus’s cosmos there is neither purpose nor ordering intelligence: everything is explained mechanically, by necessity. ...

Empedocles Empedocles (c. 494–434 BCE) was one of the most extraordinary figures of Greek philosophy: at once philosopher, physician, poet, orator, and political leader in his native city of Akragas, in Sicily. A legendary aura formed around him — he presented himself almost as a god among men, and tradition holds that he leapt into the crater of Mount Etna to confirm his divinity. He expounded his ideas in two poems, On Nature and Purifications. ...

Gorgias A native of Leontini, in Sicily, Gorgias lived, according to tradition, more than a hundred years (c. 483–375 BCE). He came to Athens in 427 BCE as ambassador of his city and dazzled the Athenians with a new oratorical style, full of figures and rhythms — becoming the most celebrated and highly paid master of rhetoric of Antiquity. Alongside Protagoras, he is the great figure of the first generation of the Sophists. ...

Heraclitus Born in Ephesus, in Ionia, and active around 500 BCE, Heraclitus belonged to an ancient aristocratic family. Proud and solitary in temperament, he wrote in a style of enigmatic aphorisms that earned him, already in antiquity, the epithet “the Obscure.” Some 126 fragments survive — dense, paradoxical, and of extraordinary poetic force. His central intuition is that of universal becoming: nothing remains, everything transforms ceaselessly — “panta rhei,” “everything flows.” Hence his most famous image: one cannot step into the same river twice, for fresh waters are ever flowing upon those who enter it. As the symbol of this perpetual flux, Heraclitus chose fire as the principle (arché): reality is like a flame that endures precisely because it is always consuming and renewing itself. ...

Laozi (老子) Essential historical note: The existence of Laozi as an individual historical figure is debated among specialists. The historian Sima Qian (c. 145–86 BCE), in the Shiji, records several traditions about Laozi without being able to decide between them — an indication that the uncertainty is ancient. The text attributed to him, the Dàodéjīng (道德經, “Classic of the Way and Virtue”, also called the Laozi), may be a compilation of material from different sources; modern scholarship places the current form of the text in the 4th or 3rd century BCE. The figure of Laozi as an ancient sage who supposedly met Confucius and then left China westward is probably legendary. ...

Mencio Note on sources: The dates of Mencius (孟子 Mèngzǐ, “Master Meng”; personal name Kē 軻) are conventional estimates — c. 372–289 BCE — based on traditional historical chronologies. The text Mèngzǐ (孟子), compiled in 7 books (piān), is considered more unified than Confucius’s Analects, although it also involved contributions from disciples in its final redaction. Mencius is honored in the Confucian tradition as the “Second Sage” (Yàshèng 亞聖), immediately below Confucius. ...

Nāgārjuna Nāgārjuna (c. 150–c. 250 CE) is the founder of the Mādhyamaka school of Mahāyāna Buddhism and is regarded in many Buddhist traditions as the second Buddha. His work exercised decisive influence on Tibetan, Chinese (and thence Japanese and Korean) Buddhism, as well as on subsequent Indian philosophy. His principal work, the Mūlamadhyamakakārikā (MMK — Fundamental Verses on the Middle Way), is one of the most commented and debated texts in the history of philosophy. ...

Parmenides Born in Elea, a Greek colony in southern Italy, and active in the first half of the fifth century BCE, Parmenides is the founder of ontology — the inquiry into being as being — and the greatest figure of the so-called Eleatic school. He expounded his thought in a philosophical poem, On Nature, of which fragments survive: in it, a young man is carried in a chariot to a goddess who reveals the truth to him. ...

Philo of Alexandria Note on dating: Philo’s dates are not known with precision; his life is estimated between c. 25/15 BCE and c. 45/50 CE, with the firmly dated embassy he led to Caligula in 39/40 CE — recounted in Legatio ad Gaium — serving as the principal point of reference. Philo of Alexandria — in Latin Philo Iudaeus, “Philo the Jew” — was a Hellenistic Jewish thinker from one of the wealthiest and most influential families of the Jewish diaspora in Alexandria. A Roman citizen, a contemporary of Jesus, Seneca, and the early Julio-Claudian emperors, he wrote entirely in Greek and stood at the crossroads of two traditions: biblical Judaism and Greek philosophy — especially Middle Platonism, Stoicism, and Pythagoreanism. In 38 CE Alexandria was the scene of violent anti-Jewish attacks under the governor Aulus Avillius Flaccus (narrated in In Flaccum), and in 39/40 CE Philo led the delegation of Alexandrian Jews that travelled to Rome to lay their grievances before Caligula. A caveat: Philo is often imprecisely labelled “Neoplatonist.” Strictly speaking, he is pre-Neoplatonist — earlier than Plotinus by more than two centuries — and is best situated within Middle Platonism. ...