A B C D E F G H I J K L M N O P R S T U V W X Z

-- A --
• Agnosticism
• Ammonius Sakkas (c. 175 – 242)
• Ampère, André-Marie (1775 – 1836)
• Anaxagoras (c. 500 B.C.)
• Anaximander (611 – 550 B.C.)
• Anaximenes (c. 600 B.C.)
• Angelus Silesius (Johann Scheffler, 1624 – 1677)
• Anselm of Canterbury (1033 – 1109)
• Anthropomorphism
• Apollonius of Tyana (c. 50 A.D.)
• Archytas (c. 400 – 365 B.C.)
• Aristophanes (c. 450 – 385 B.C.)
• Aristotle (384 – 322 B.C.)
• Asmus, Paul (1842 – 1876)
• Atomists
• Augustine, St. Aurelius (354 – 430)
• Averroës (1126 – 1198)

-- B --
• Baader, Franz Xaver Benedikt von (1765 – 1841)
• Bacon, Francis (1561 – 1626)
• Baer, Carl Ernst von (1792 – 1876)
• Bain, Alexander, (1818 – 1903)
• Balfour, Arthur James (1848 – 1930)
• Basilides (c. 130 A.D.)
• Bauer, Bruno (1809 – 1882)
• Beck, Jakob Sigismund (1761 – 1840)
• Bergson, Henri (1859 – 1941)
• Berkeley, George (1684 – 1753)
• Bernardinus Telesius, see Telesius
• Boehme, Jakob (1575 – 1624)
• Boutroux, Emile (1845 – 1921)
• Brentano, Franz (1838 – 1917)
• Bruno, Giordano (1548 – 1600)
• Buechner, Ludwig (1824 – 1899)
• Burdach, Karl Friedrich (1776 – 1847)

-- C --
• Cabanis, Pierre Jean Georges (1757 – 1808)
• Cardanus, Hieronymus (1501 – 1576)
• Carneri, Bartholomäus von (1821 – 1909)
• Cassirer, Ernst (1874 – 1945)
• Chalybäs, Heinrich Moritz (1796 – 1862)
• Chrysippus (280 – 208 B.C.)
• Clemens of Alexandria (died 211 A.D.)
• Cohen, Hermann (1842 – 1918)
• Comte, Auguste (1798 – 1857)
• Condillac, Etienne Bonnot de Mably de (1715 – 1780)
• Copernicus, Nicholas (1473 – 1543)
• Cousin, Victor (1792 – 1067)
• Cratylus (Plato's teacher)
• Critias (Pupil of Socrates)
• Cusanus, Nicolaus
• Cuvier, Georges Baron de (1769 – 1832)
• Czolbe, Heinrich (1819 – 1873)

-- D --
• Dante Alighieri (1265 – 1321)
• Darwin, Charles (1809 – 1882)
• Democritus (c. 460 – 371 B.C.)
• Descartes, René (1596 – 1650)
• Destutt de Tracy, Antoine Louis Claude (1754 – 1836)
• Deutinger, Martin van (1815 – 1864)
• Diderot, Denis (1713 – 1784)
• Dilthey, Wilhelm (1833 – 1911)
• Dionysius the Areopagite
• Dubois, Eugen (1858 – 1940)
• Du Bois-Reymond, Emil (1815 – 1896)
• Dühring, Eugen (1833 – 1921)

-- E --
• Echtermeyer, Ernst Theodor (1805 – 1844)
• Eckhardt, Meister, see Meister Eckhardt
• Einstein, Albert (1879 – 1955)
• Eleatics
• Empedocles (483 – 424 B.C.)
• Encyclopedists
• Epicureans
• Epicurus (342 – 270 B.C.)
• Erdmann, Benno (1851 – 1921)
• Erdmann, Johann Eduard (1805 – 1892)
• Eucken, Rudolf (1846 – 1926)

-- F --
• Faraday, Michael (1791 – 1867)
• Fechner, Gustav Theodor (1801 – 1887)
• Feuerbach, Ludwig (1804 – 1872)
• Fichte, Immanuel Hermann (1797 – 1879)
• Fichte, Johann Gottlieb (1762 – 1814)
• Fischer, Karl Philip (1824 – 1908)
• Flechsig, Paul (born 1847)
• Forberg, Friedrich (1770 – 1848)
• Frantz, Constantin (1817 – 1891)
• Fries, Jakob Friedrich (1773 – 1843)

-- G --
• Galilei, Galileo (1564 – 1642)
• Gegenbaur, Karl (1826 – 1903)
• Geoffroy de St. Hilaire, Etienne (1772 – 1844)
• Gladstone, William Ewart (1809 – 1898)
• Gnosis
• Goethe, Johann Wolfgang von (1749 – 1832)
• Gompertz, Theodor (1832 – 1912)
• Gorgias (died after 399 B.C.)
• Grillparzer, Franz (1791 – 1872)
• Guenther, Anton (1783 – 1863)

-- H --
• Haeckel, Ernst (1834 – 1919)
• Hailer, Albrecht von (1708 – 1777)
• Hamann, Johann Georg (1730 – 1788)
• Hamerling, Robert (1830 – 1889)
• Hamilton, William (1788 – 1856)
• Hartmann, Eduard van (1842 – 1906)
• Harvey, William (1578 – 1657)
• Hegel, Georg Wilhelm Frederich (1770 – 1831)
• Heinroth, Johann Christian (1773 – 1843)
• Helmholtz, Hermann von (1821 – 1894)
• Helvetius, Claude Adrien (1715 – 1771)
• Hemsterhuis, Franz (1721 – 1790)
• Henle, Jakob (1809 – 1885)
• Heraclitus (c. 540 – 480 B.C.)
• Herbart, Johann Friedrich (1776 – 1841)
• Herder, Johann Gottfried (1744 – 1803)
• Herschel, John (1792 – 1871)
• Hippias (c. 400 B.C.)
• Hobbes, Thomas (1588 – 1679)
• Hoff, Karl von (1771 – 1837)
• Hoffman, Franz (1804 – 1881)
• Holbach, Paul Heinrich Dietrich von (1723 – 1789)
• Humboldt, Alexander von (1769 – 1859)
• Humboldt, Wilhelm von (1767 – 1835)
• Hume, David (1711 – 1776)
• Huxley, Thomas Henry (1825 – 1895)

-- I --
• Iamblichus (c. 330 A.D.)

-- J --
• Jacobi, Friedrich Heinrich (1743 – 1819)
• James, William (1842 – 1910)
• Jean Paul, see Richter

-- K --
• Kant, Immanuel (1724 – 1804)
• Kepler, Johannes (1571 – 1630)
• Key, Ellen (1849 – 1926)
• Kinkel, Walter (born 1871)
• Kirchhoff, Gustav Robert (1824 – 1887)
• Kirchmann, Julius Heinrich (1807 – 1884)
• Kleanthes
• Kräpelin, Emil (1856 – 1926)
• Krause, Karl Christian Friedrich (1781 – 1832)

-- L --
• Laas, Ernst (1837 – 1885)
• Lamarck, Jean (1749 – 1829)
• La Mettrie, Julien de (1709 – 1751)
• Lang, Arnold
• Lange, Friedrich Albert (1828 – 1875)
• Laplace, Pierre Simone (1749 – 1827)
• Lassalle, Ferdinand (1825 – 1864)
• Lavoisier, Antoine Laurent (1743 – 1794)
• Leclair, Anton von (born 1845)
• Leibniz, Gottfried Wilhelm von (1646 – 1716)
• Leonardo da Vinci (1452 – 1519)
• Lessing, Gotthold Ephraim (1729 – 1781)
• Leucippus (c. 450 B.C.)
• Lichtenberg, Georg Christoph (1742 – 1799)
• Liebmann, Otto (1840 – 1912)
• Linnaeus, Karl von (Linné, Carl von) (1707 – 1778)
• Locke, John (1632 – 1704)
• Lotze, Hermann (1817 – 1881)
• Lucretius Carus, Titus (96 – 55 B.C.)
• Lyell, Charles (1797 – 1875)

-- M --
• Mackay, John Henry (1864 – 1933)
• Maimon, Salomon (1753 – 1800)
• Maimonides (1135 – 1204)
• Mainländer, Philipp (1841 – 1876)
• Maine de Biran, François Pierre Gauthier (1766 – 1824)
• Malthus, Thomas Robert (1766 – 1834)
• Mansel, Henry (1820 – 1871)
• Marcion (died c. 170 A.D.)
• Marsch (Marsh, Othniel Charles? (1831 – 1899))
• Marx, Karl (1818 – 1883)
• Mayer, Julius Robert (1814 – 1878)
• Meister Eckhardt (1260 – 1327)
• Melissos (c. 450 B.C.)
• Mendelssohn, Moses (1729 – 1786)
• Mettrie, see La Mettrie
• Michelet, Carl Ludwig (1801 – 1893)
• Mill, James (1773 – 1836)
• Mill, John Stuart (1806 – 1873)
• Moderatus (1st Century A.D.)
• Moleschott, Jacob (1822 – 1893)
• Mueller, Johannes (1801 – 1858)
• Müller, Fritz

-- N --
• Natorp, Paul (1854 – 1924)
• Naville, Jules Ernest (1816 – 1909)
• Nehring, Alfred (1845 – 1904)
• Neo-Platonism
• Newton, Isaac (1642 – 1727)
• Nietzsche, Friedrich (1844 – 1900)
• Nigidius Figulus (c. 95 – 45 B.C.)
• Nominalism
• Novalis (Friedrich Georg van Hardenberg) (1772 – 1801)

-- O --
• Oken, Lorenz (1779 – 1851)
• Oersted, Hans Christian (1777 – 1851)
• Origenes (Origen) (c. 183 – 252)
• Orphics

-- P --
• Paracelsus (1493 – 1541)
• Parmenides (born c. 540 B.C.)
• Pierce, Charles (1839 – 1914)
• Pherekydes of Syros (6th Century B.C.)
• Philo of Alexandria (20 – 50 A.D.)
• Philolaus (c. 450 B.C.)
• Planck, Karl Christian (1819 – 1880)
• Plato (427 – 347 B.C.)
• Plotinus (205 – 270)
• Porphyrius (232 – 304)
• Post-Kantians
• Pragmatism
• Prel, Carl du (1839 – 1899)
• Preuss, Wilhelm Heinrich (born 1809)
• Prodicus (contemporary of Socrates)
• Proclus (410 – 485)
• Protagoras (c. 480 – 410 B.C.)
• Pyrrho (360 – 270 B.C.)
• Pythagoras (582 – 493 B.C.)

-- R --
• Realism
• Rehmke, Johannes (1848 – 1930)
• Reid, Thomas (1710 – 1756)
• Reinhold, Karl Leonhard (1758 – 1823)
• Relativity, Theory of
• Reuschle, Karl Gustav
• Rickert, Heinrich (1863 – 1936)
• Richter, Jean Paul Friedrich (1763 – 1825)
• Riehl, Alois (1844 – 1924)
• Rolph, W. H.
• Romanticism
• Roscellin, Johannes (c. 1050 – 1123)
• Rosenkranz, Johann Karl Friedrich (1805 – 1879)
• Rosenthal, Isidor (1836 – 1915)
• Rousseau, Jean Jacques (1712 – 1778)
• Ruge, Arnold (1802 – 1880)

-- S --
• Saint-Simon, Claude-Henri de (1760 – 1825)
• Schelling, Friedrich Wilhelm Josef (1775 – 1854)
• Schiller, Ferdinand Canning Scult (1864 – 1937)
• Schiller, Friedrich (1759 – 1805)
• Schlegel, Friedrich (1772 – 1829)
• Schleiden, Matthias Jacob (1804 – 1881)
• Schleiermacher, Friedrich Ernst (1768 – 1834)
• Schopenhauer, Arthur (1788 – 1860)
• Schubert-Soldern, Richard von (born 1852)
• Schulze, Gottlob Ernst (1761 – 1833)
• Schuppe, Wilhelm (1836 – 1913)
• Schwann, Theodore (1810 – 1882)
• Scotus Erigena (c. 810 – 877)
• Seiling, Max
• Sengler, Jacob (1799 – 1878)
• Shaftesbury, Anthony Ashley Cooper (1671 – 1713)
• Shakespeare (1564 – 1616)
• Scepticism
• Socrates (469 – 399 B.C.)
• Solger, Karl Wilhelm Ferdinand (1780 – 1819)
• Sophists
• Soret, Friedrich Jacob (1795 – 1865)
• Spencer, Herbert (1820 – 1903)
• Spicker, Gideon (1840 – 1912)
• Spinoza, Baruch (1632 – 1677)
• Stadler, August (1850 – 1910)
• Steffens, Henrik (1773 – 1845)
• Stirner, Max (1806 – 1856)
• Stoics
• Strauss, David Friedrich (1808 – 1874)
• Suso, Heinrich (c. 1300 – 1366)

-- T --
• Taine, Hippolyte (1828 – 1893)
• Tauler, Johannes (c. 1300 – 1361)
• Telesius, Bernardinus (1509 – 1588)
• Tetens, Johann Nikolaus (1736 – 1807)
• Thales (c. 625 – 545 B.C.)
• Theology, German
• Thomas Aquinas (1227 – 1274)
• Thrahndorff, Karl Friedrich Eusebius (1782 – 1863)
• Thrasymachus (contemporary of Socrates)
• Tolstoi, Leo (1828 – 1910)
• Treitschke, Heinrich von (1834 – 1896)
• Trendelenburg, Friedrich Adolf (1802 – 1872)
• Troxler, Ignaz Paul Vitalis (1780 – 1866)
• Tyndall, John (1820 – 1893)

-- U --
• Ulrici, Hermann (1806 – 1884)

-- V --
• Vaihinger, Hans (1852 – 1933)
• Valentinus (died c. 160 A.D.)
• Virchow, Rudolf (1821 – 1903)
• Vischer, Friedrich Theodor (1807 – 1887)
• Vogt, Karl (1817 – 1895)
• Volkelt, Johannes Immanuel (1848 – 1930)
• Volta, Alessandro (1743 – 1827)
• Voltaire, Jean Marie Aroriet (1694 – 1778)

-- W --
• Wackernagel, Wilhelm (1806 – 1869)
• Wagner, Richard (1813 – 1883)
• Wagner, Rudolf (1805 – 1864)
• Wahle, Richard (died 1857)
• Weber, Ernst Heinrich (1795 – 1878)
• Weisse, Christian Hermann (1801 – 1866)
• Whewell, William (1794 – 1866)
• Wieland, Christoph Martin (1733 – 1813)
• Winckler, Johann Heinrich (1703 – 1770)
• Windelband, Wilhelm (1848 – 1915)
• Windischmann, Karl Joseph Hieronymus (1775 – 1839)
• Wirth
• Woehler, Friedrich (1800 – 1882)
• Wolff, Casper Friedrich (1733 – 1794)
• Wolff, Christian (1679 – 1754)
• Wundt, Wilhelm (1832 – 1920)

-- X --
• Xenophon (c. 500 B.C.)
• Xenophanes (born c. 580 B.C.)

-- Z --
• Zeller, Eduard (1814 – 1908)
• Zeno (Zenon) of Elea (c. 500 B.C.)
• Zeno of Kition (342 – 270 B.C.)
• Zimmerman, Robert (1824 – 1898)