Aristotelianism

Introduction

Aristotelianism is the tradition founded by Plato's most consequential student — who took the framework and then disagreed with it on the deepest point. Forms are real, but they are in things, not separate from them. The fix was small and the consequences were enormous.

Founding moment

Founded by Aristotle (384 – 322 BCE), who studied with Plato in the Academy for nearly twenty years before founding his own school, the Lyceum, in 335 BCE. The students were called peripatetics — those who walk around — supposedly because Aristotle lectured while walking the school's covered walkway.

Aristotle had also tutored a young Alexander the Great, who would shortly conquer most of the known world and disseminate Greek learning across it. The accident of timing matters: Aristotelian thought traveled on Alexander's roads, was preserved in Alexandria, and became the inheritance of the Hellenistic and then Islamic worlds.

Core doctrines

1. Forms are immanent. Against Plato, Aristotle insisted forms exist in the particular things that have them, not in a separate realm. The form of horse exists in actual horses; there is no transcendent Horse over and above them. This is the hylomorphic position: every substance is a unity of matter (hyle) and form (morphe).
2. The four causes. Every change or thing has four kinds of explanation — material (what it's made of), formal (what it is), efficient (what brought it about), and final (what it's for). To understand anything is to grasp all four causes.
3. Teleology pervades nature. Everything in nature has a telos, an end toward which it tends. An acorn aims at being an oak. A knife aims at cutting. A human aims at the activity of the rational soul in accordance with virtue.
4. Eudaimonia is the human telos. The good life is rational activity in accordance with virtue, across a complete life, with sufficient external goods. This is the canonical statement of virtue ethics.
5. Virtue is a mean between two extremes. Every virtue lies between a deficiency and an excess: courage between cowardice and rashness, generosity between miserliness and prodigality. Practical wisdom (phronesis) finds the mean in the situation.
6. Knowledge starts with sense experience. Against Platonic recollection, Aristotle argued the intellect begins as a blank slate (tabula rasa) and acquires knowledge through abstraction from observed particulars. This is the seed of empiricism.
7. The unmoved mover. Aristotle's metaphysics requires a first cause — something that moves without itself being moved, the source of all motion. Aquinas would later identify this with God.

Major figures

• Aristotle himself — the founder. The surviving works are mostly lecture notes, not polished dialogues, which makes them harder to read than Plato but more substantive.
• Theophrastus — immediate successor at the Lyceum.
• Alexander of Aphrodisias (~200 CE) — the most important ancient commentator.
• Avicenna and Averroes (11th–12th centuries) — the great Islamic Aristotelians; transmitted Aristotle back to the Latin West through their commentaries.
• Thomas Aquinas (1225 – 1274) — the supreme Christian Aristotelian; baptized the system into Catholic theology.
• Alasdair MacIntyre (1929 – ) — the most important modern Aristotelian; After Virtue (1981) reignited virtue ethics by recovering the Aristotelian framework.

Major texts

• Nicomachean Ethics — the foundational text in virtue ethics. Probably the single most-read philosophical work after Plato's Republic.
• Metaphysics — the analysis of being qua being, substance, causation, and the unmoved mover.
• Politics — humans as political animals; analysis of regime types.
• Physics — the study of nature, motion, change, causation.
• De Anima — the soul as the form of a living body; the cognitive faculties.
• Organon — the collected logical works that grounded Western formal logic for two millennia.

Internal tensions and rival schools

Aristotle's most acute internal tension is between the empiricist strand (knowledge from sense experience) and the rationalist demands (the first principles of demonstration must be self-evident). How the mind gets from particulars to universals — the famous abstraction problem — is never fully resolved.

The main rival has always been Platonism. The Platonism–Aristotelianism debate runs through every era: in the Hellenistic period the Stoics borrowed from both; in late antiquity Plotinus tried to synthesize them; in the Middle Ages Aquinas Aristotelianized Christian theology while Augustinians remained Platonist; the Renaissance had Florentine Platonists arguing against scholastic Aristotelians; the early modern period saw both eclipsed (and then partially recovered).

Legacy

Aristotle's legacy is staggering. He effectively invented Western formal logic — the syllogistic system in the Organon was the only logical system anyone used until the 19th century. He founded the empirical study of biology with careful observations that were still being cited centuries later.

He became the central authority of medieval scholarship through the Islamic world (Avicenna, Averroes) and then through Latin Christianity (Aquinas). For centuries he was called simply the Philosopher. To cite the Philosopher said was to cite a settled question.

The Scientific Revolution was, in significant part, a revolt against Aristotelian physics. But the methodological insistence on observation, the demand for explanations in terms of causes, and the empirical temperament — these survived and underwrite modern science.

In the 20th century, virtue ethics returned through Anscombe, Foot, MacIntyre, and Nussbaum, all working within or developing the Aristotelian framework. MacIntyre's After Virtue is the most influential single revival, arguing that ethics without an Aristotelian conception of human telos cannot ground itself.

Contemporary Aristotelianism is unusually active. Neo-Aristotelian virtue ethics (Anscombe, Foot, MacIntyre, Hursthouse, Nussbaum) is one of the major positions in normative ethics. Aristotelian metaphysics has been recovered in contemporary analytic work on substance, essence, and powers (E.J. Lowe, Kit Fine, Tuomas Tahko). Aristotelian philosophy of biology continues through the work of Marjorie Grene, James Lennox, and Allan Gotthelf. The recovery of phronesis as a model for practical reasoning is active in philosophy of action and applied ethics.

Foundational tradition. The empirical, immanent counter-pole to Platonic transcendence.