| Ancient | Confucius | Filial piety, humaneness, ritual | Moral philosophy, Chinese thought | Traditional Chinese beliefs | Ethicist, political philosopher | 551 BCE – 479 BCE |
| Ancient | Heraclitus | Unity of opposites, flux (change), Logos | Pre-Socratic thought, concept of change and impermanence | None (pre-Socratic philosopher) | Metaphysicist, materialist | 535 BCE – 475 BCE |
| Ancient | Socrates | Socratic method, ethics | Foundation of Western ethical philosophy | None (predecessor to Plato) | Ethicist, dialectician | 470 BCE – 399 BCE |
| Ancient | Plato | Theory of Forms, Platonic realism | Foundation of Western philosophy and science | Socrates | Metaphysicist, ethicist | 427 BCE – 347 BCE |
| Ancient | Aristotle | Golden mean, logic, metaphysics, ethics | Formal logic, empirical science basis | Plato | Empiricist, ethicist | 384 BCE – 322 BCE |
| Ancient | Epicurus | Atomism, hedonism, absence of pain (ataraxia) | Philosophy of pleasure, ethics | Democritus, Aristippus | Hedonist, materialist | 341 BCE – 270 BCE |
| Ancient | Zeno of Citium | Stoicism, living in accordance with nature | Founder of Stoicism, philosophy of virtue and reason | Socrates, Cynicism | Stoic philosopher | 334 BCE – 262 BCE |
| Ancient | Pyrrho | Skepticism, ataraxia (mental tranquility) | Founder of Pyrrhonism, skepticism | Democritus, Socratic philosophy | Skeptic, philosopher | 360 BCE – 270 BCE |
| Ancient | Diogenes | Cynicism, rejection of societal conventions | Development of Cynicism, influence on Stoicism | Socrates, Antisthenes | Cynic philosopher | 412 BCE – 323 BCE |
| Ancient | Seneca | Stoicism, ethics, practical wisdom | Stoic ethics, influence on Roman and modern thought | Zeno, Chrysippus | Stoic philosopher, ethicist | 4 BCE – 65 CE |
| Medieval | Augustine of Hippo | Original sin, City of God vs. City of Man | Christian doctrine, integration of philosophy & theology | Plato, Christianity | Theologian, philosopher | 354 CE – 430 CE |
| Medieval | Avicenna (Ibn Sina) | Islamic philosophy, metaphysics, medicine | Integration of Aristotelian philosophy with Islamic thought | Aristotle, Islamic philosophy | Metaphysicist, physician | 980 CE – 1037 CE |
| Medieval | Thomas Aquinas | Natural law, theology, and integration of Aristotelian philosophy with Christianity | Summa Theologica, bridging faith and reason | Aristotle, Augustine | Scholastic philosopher | 1225 – 1274 |
| Early Modern | Francis Bacon | Empiricism, scientific method | Development of the scientific method | Aristotle | Empiricist, scientist | 1561 – 1626 |
| Renaissance | René Descartes | Cogito, ergo sum; methodic doubt | Father of modern philosophy, Cartesian dualism | Aristotle, Aquinas | Rationalist | 1596 – 1650 |
| Early Modern | Thomas Hobbes | Social contract theory, materialism | Political philosophy, foundation of Western political thought | Bacon, Aristotle | Materialist, political philosopher | 1588 – 1679 |
| Early Modern | Baruch Spinoza | Pantheism, ethics, geometric method | Ethical philosophy, rationalism, metaphysics | Descartes, Jewish philosophical tradition | Rationalist, ethicist | 1632 – 1677 |
| Enlightenment | John Locke | Tabula rasa, natural rights, government by consent | Empiricism, political liberalism | Bacon, Hobbes | Empiricist, political philosopher | 1632 – 1704 |
| Enlightenment | Montesquieu | Separation of powers, classification of governments | Major influence on political theory, especially constitutional government | Locke, Aristotle | Political philosopher | 1689 – 1755 |
| Enlightenment | Voltaire | Critique of the Church, advocacy of freedom of speech, separation of church and state | Literature, history, advocacy for civil liberties | Locke, Newton | Writer, philosopher, historian | 1694 – 1778 |
| Enlightenment | David Hume | Empiricism, skepticism, naturalism | Empirical approach to human nature, theory of knowledge | Locke, Berkeley | Empiricist, skeptic | 1711 – 1776 |
| Enlightenment | Jean-Jacques Rousseau | Social contract, general will, noble savage | Political philosophy, education, and ethics | Hobbes, Montesquieu | Political philosopher, educator | 1712 – 1778 |
| Enlightenment | Immanuel Kant | Categorical imperative, Critique of Pure Reason | Deontological ethics, epistemology | Hume, Rousseau | Idealist, ethicist | 1724 – 1804 |
| 19th Century | Georg Wilhelm Friedrich Hegel | Dialectics, absolute idealism, master-slave dialectic | Development of dialectical idealism, influence on Marxism | Kant, Fichte | Idealist, dialectician | 1770 – 1831 |
| 19th Century | John Stuart Mill | Utilitarianism, liberty, freedom of speech | Ethical theory of utilitarianism, political liberalism | Bentham, Aristotle | Utilitarian, political philosopher | 1806 – 1873 |
| 19th Century | Karl Marx | Materialist conception of history, class struggle | Marxism, critique of political economy | Hegel, Feuerbach | Political philosopher, economist | 1818 – 1883 |
| 19th Century | Friedrich Nietzsche | Will to power, eternal recurrence, the Übermensch | Critique of morality, religion, and philosophy | Schopenhauer, Wagner | Existentialist, cultural critic | 1844 – 1900 |
| 20th Century | Ludwig Wittgenstein | Limits of language, picture theory of language | Analytic philosophy, philosophy of language | Russell, Frege | Analytic philosopher | 1889 – 1951 |
| 20th Century | Martin Heidegger | Being and Time, existential ontology | Development of existential phenomenology | Husserl, Nietzsche | Existentialist, phenomenologist | 1889 – 1976 |
| 20th Century | Jean-Paul Sartre | Existence precedes essence, freedom and responsibility | Existentialism, phenomenology | Husserl, Heidegger | Existentialist, phenomenologist | 1905 – 1980 |
