Philosophy | Definition, Systems, Fields, Schools, & Biographies | Britannica (2025)

philosophy, (from Greek, by way of Latin, philosophia, “love of wisdom”) the rational, abstract, and methodical consideration of reality as a whole or of fundamental dimensions of human existence and experience. Philosophical inquiry is a central element in the intellectual history of many civilizations.

The subject of philosophy is treated in a number of articles. For discussion of major systems of Eastern philosophy, see Buddhism; Chinese philosophy; Confucianism; Daoism; Hinduism; Indian philosophy; Jainism; Japanese philosophy; Shintō; Sikhism.

For biographies of major Eastern philosophers, see Buddha; Confucius; Dai Zhen; Han Feizi; Laozi; Mencius; Mozi; Nichiren; Nishida Kitarō; Wang Yangming; Xunzi; Zhu Xi.

For historical coverage of Western philosophy, see Western philosophy. For discussion of philosophies associated with the major religious traditions of the West, see Christianity: Christian philosophy; Islam: Islamic philosophy; Judaism: Jewish philosophy.

For discussion of major Western schools, movements, and systems, see atomism; analytic philosophy; Continental philosophy; deconstruction Eleaticism; empiricism; existentialism; idealism; materialism; phenomenology; positivism; postmodernism; pragmatism; rationalism; realism; Scholasticism; skepticism; Stoicism; utilitarianism.

For biographies of major Western philosophers and treatment of their associated movements, see Aristotle and Aristotelianism; René Descartes and Cartesianism; Epicurus and Epicureanism; Georg Wilhelm Friedrich Hegel and Hegelianism; Immanuel Kant and Kantianism; Karl Marx and Marxism; Plato and Platonism; Pythagoras and Pythagoreanism.

For discussion of other major Western philosophers, see Peter Abelard; St. Anselm; St. Thomas Aquinas; St. Augustine; Noam Chomsky; Jacques Derrida; Duns Scotus; Michel Foucault; Jürgen Habermas; Martin Heidegger; David Hume; William James; Saul Kripke; Gottfried Wilhelm Leibniz; John Locke; John Stuart Mill; Friedrich Nietzsche; Hilary Putnam; Jean-Jacques Rousseau; Bertrand Russell; Jean-Paul Sartre; Socrates; Benedict de Spinoza; Bernard Williams; Ludwig Wittgenstein.

For coverage of the particular branches of Western philosophy, see aesthetics; epistemology; ethics; ideology; logic; metaphysics; philosophical anthropology; philosophy of biology; philosophy of education; philosophy of history; philosophy of language; philosophy of law; philosophy of logic; philosophy of mathematics; philosophy of mind ; philosophy of physics; philosophy of religion; philosophy of science.