Aristotle
Ancient Greek · Europe · 384 to 322 BCE
Student of Plato who studied nature and ethics. He taught that a good life means building good character and sound judgment.
What it is
Aristotle (384 to 322 BCE) was a Greek philosopher and scientist who studied with Plato, founded the first formal system of logic, observed living things in careful detail, and held that the good life consists in developing excellence of character and reason. Judged by his philosophical influence, only Plato is his equal, and his works shaped centuries of thought from the end of antiquity through the Renaissance.
He was born in the small city of Stagira, in the Macedonian region of northeastern Greece, and he spent many years as a student of Plato in Athens. He later tutored Alexander, the boy who became Alexander the Great, and he founded his own school in Athens, the Lyceum. His followers became known as Peripatetics. He wrote on a very wide range of subjects, perhaps two hundred works in all, of which about thirty-one survive.
The main ideas
- Logic. Aristotle was the first to work out a formal system of reasoning. He saw that an argument can be valid because of its structure and not because of what it is about.
- Observation first. His natural science rests on watching things closely. He studied plants and animals in detail, and he combined logic with observation to make general claims about causes. In this he was more empirically minded than Plato.
- Matter and form. He described natural things as made of matter and form together. A living thing, for instance, is a body and the form that makes it the kind of thing it is.
- Against Plato's Forms. He rejected the theory that eternal Forms exist apart from the things they explain, partly because he thought it could not account for change.
- An unchanging source. At the base of his metaphysics he argued for a separate and unchanging being that is the source of the movement and being of everything else.
- Happiness through excellence. In ethics he held that a person can reach the best kind of human life, called eudaimonia, only by becoming excellent in character and in reasoning. He treats happiness and life in a political community together, because we flourish among other people.
What it looks like in practice
Picture someone who wants to understand why a plant grows toward the light, or why a quarrel in their family keeps coming back. An Aristotelian begins by looking: gather what can be observed, sort it into kinds, and then ask what each thing is for and what it is made of. Only then does the explanation come. The habit is to start from how things actually are, and to ask what a good example of a thing would be like.
Works and moments
- The Lyceum was the school he founded in Athens. His followers there became known as Peripatetics.
- His surviving treatises number about thirty-one, out of perhaps two hundred he wrote.
- Teacher of Alexander. He tutored the young Alexander, who became Alexander the Great, at the Macedonian court.
Questions and criticism
- What did he really mean? The wide range of the works and the long history of readers who adapted them mean that even basic points of interpretation are disputed.
- Is the unmoved mover needed? It is fair to ask whether an argument for an unchanging first source of all motion succeeds, and whether the world needs one at all.
- Is excellence enough for a good life? If flourishing comes from excellent character and reasoning, it is fair to ask how far luck and circumstances matter.
Close neighbours
Aristotle was a student of Plato who rejected Plato's Forms. His ethics is the source of the tradition of virtue ethics, described on the page on Aristotelian virtue ethics. Over more than two thousand years, philosophers in many religious and secular traditions have interpreted and used his works.
Written by epchē in our own words, and checked against independent sources on 9 October 2026. The sources are listed below.
Where to start reading
Books by Aristotle or about them, from the easiest way in to the harder ones.
Covers belong to their publishers and are shown so you can recognise the book.
Philosophies they belong to or are close to
Who they connect to
Influenced
- Al-Farabi · Al-Farabi wrote commentaries on Aristotle's logic and was known as the second teacher.
- Alasdair MacIntyre · MacIntyre rebuilds ethics on an Aristotelian account of the virtues and human ends.
- Averroes (Ibn Rushd) · Averroes' commentaries on Aristotle earned him the title of the Commentator.
- Bernard Williams · Williams returned to Greek ethics as a model of morality tied to character and luck. (scholars disagree about this link)
- Boethius · Boethius planned to translate and comment on Aristotle's logic, which the Latin west then studied for centuries.
- Elizabeth Anscombe · Anscombe pointed to Aristotle for a moral psychology of intention, virtue and human flourishing.
- Franz Brentano · He wrote his first book on Aristotle and took up his account of the soul.
- Hannah Arendt · Arendt drew on Aristotle's distinction between action, making and labour.
- Ibn Miskawayh · His ethics follows Aristotle's account of virtue as a mean between extremes.
- Ibn Sina (Avicenna) · Ibn Sina built on Aristotle as read through earlier Arabic translators.
- John Duns Scotus · Scotus worked in the Aristotelian framework of medieval universities while departing from it on will and being.
- Moses Maimonides · The Guide for the Perplexed uses Aristotle's science and his ideas about the basic nature of reality as its background.
- Philippa Foot · Foot's natural goodness account is based on an Aristotelian view of living things.
- Plotinus · Plotinus used Aristotelian ideas of actuality and intellect inside a Platonic frame.
- Thomas Aquinas · Aquinas wrote commentaries on Aristotle and built his moral and natural philosophy on them.
Influenced by
- Plato · Aristotle studied in Plato's Academy for about twenty years before breaking with several of his teachings.
Reacted against
- Democritus · Aristotle argued against atoms and the void in his physics.
- Plato · Aristotle rejected Plato's separate realm of forms in favour of forms found in things.
Reacted against by
- Francis Bacon · Bacon's Novum Organum was written to replace the Aristotelian way of reasoning from first principles.
Other Ancient Greek thinkers
- Thales of Miletus · 624 to 546 BCE
- Anaximander · 610 to 546 BCE
- Anaximenes · 586 to 526 BCE
- Pythagoras · 570 to 495 BCE
- Xenophanes · 570 to 475 BCE
- Heraclitus · 535 to 475 BCE
- Parmenides · 515 to 450 BCE
- Anaxagoras · 500 to 428 BCE
- Empedocles · 494 to 434 BCE
- Zeno of Elea · 490 to 430 BCE