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- Charles Maurras (1868–1952)
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- Charles Taylor (1931–)
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- Cheung Kam Ching
- Ching-Lai Sheng[5]: 553–554
- Chris Cuomo
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- Chrysippus (Greece, c. 280 BC – c. 207 BC)
- Cicero
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- Claude Adrien Helvétius
- Claude Adrien Helvétius[10]
- Claude Lefort
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- Colin Wilson
- Confucius
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- Constantin Rădulescu-Motru (Romania, 1868–1957)
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- Cornelius Castoriadis (1922–1997)
- Cressida Heyes
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- D
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- Dag Prawitz (Sweden, born 1936)
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- Dale Jamieson
- Damascius
- Dan Goldstick[41]
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- David George Ritchie[5]: 483–484
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- David Lewis
- David Makinson (Australia, UK, born 1941)
- David Malet Armstrong
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- David Olivier[52]
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- David Schmidtz
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- Dylan Matthews[49]
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- Edmund Gettier
- Edmund Husserl
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- Eduard Bernstein (1850–1932)
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- Edward Burnett Tylor
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- Edward Livingston[5]: 313–315
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- Edward Said (1935–2003)
- Edwin Chadwick[5]: 75–77
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- Empedocles
- Enrique Dussel
- Epicurus
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- Esperanza Guisán[28]
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- Eugen Rosenstock-Huessy
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- F
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- Félicité de La Mennais (1782–1854)
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- Félix Guattari (1930–1992)
- Félix Guattari[29]
- Felix Kaufmann
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- Francisco de Vitoria
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- Francisco Suárez
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- Fyodor Shcherbatskoy (Russia, 1866–1942)
- G
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- G. E. Moore
- G. E. Moore[5]: 356–359
- G. K. Chesterton
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- Gareth Evans
- Garlandus Compotista (France, c. 11th century)
- Gary R. Mar (US, born 1952)
- Gaston Bachelard
- Gautama Buddha
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- Gene Youngblood
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- George Bentham[5]: 44–46
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- H
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- H. L. A. Hart[5]: 216–221
- H. Richard Niebuhr
- Hai Gaon
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- Haskell Curry (US, 1900–1982)
- Hasok Chang
- Hastings Rashdall[5]: 463–465
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- Henry Fawcett[5]: 161–163
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- Henry Sidgwick[5]: 531–534
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- Hsun Tzu
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- Hugo Grotius
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- Hui Shi (China, fl. 4th century BC)
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- Hypatia
- I
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- Israr Ahmed
- Ivan Ilyin (1883–1954)
- Ivan Orlov (Russia, 1886–1936)
- J
- J. Baird Callicott, University of North Texas
- J. Barkley Rosser (US, 1907–1989)
- J. Howard Moore[26]
- J. J. C. Smart
- J. J. C. Smart[33]
- J. L. Austin
- J. L. Mackie
- J.P. Moreland
- Jaakko Hintikka
- Jaakko Hintikka (Finland, 1929–2015)
- Jack Copeland (UK, born 1950)
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- Jacob Abendana
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- Jacopo Zabarella (Italy, 1533–1589)
- Jacques Bouveresse
- Jacques Derrida
- Jacques Derrida (1930–2004)
- Jacques Derrida[24]
- Jacques Herbrand (France, 1908–1931)
- Jacques Lacan
- Jacques Lacan[34]
- Jacques Maritain
- Jacques Maritain (1882–1973)
- Jacques Rancière
- Jacques Rancière (1940–)
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- Jacques-Bénigne Bossuet (1627–1704)
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- James Hatley, Salisbury University
- James Hinton
- James Lovelock
- James M. Edie
- James MacKaye[24]
- James Madison
- James Madison (1751–1836)
- James Martineau
- James Mill
- James Mill (1773–1836)
- James Mill[14]
- James Rachels
- Jan Deckers, Newcastle University
- Jan Łukasiewicz (Poland, 1878–1956)
- Jason Stanley
- Jaun Elia
- Jawaharlal Nehru
- Jawaharlal Nehru (1889–1964)
- Jay Rosenberg
- Jayanta Bhatta (India, 850–910)
- Jayatirtha
- Jean Anthelme Brillat-Savarin
- Jean Baptiste Say[5]: 497–499
- Jean Baudrillard
- Jean Baudrillard[16]
- Jean Bodin
- Jean Bodin (1530–1596)
- Jean Buridan
- Jean Buridan (France, c. 1300–post 1358)
- Jean Capréolus
- Jean Curthoys
- Jean Gerson (1363–1429)
- Jean Grondin
- Jean Nicod (France, 1893–1924)
- Jean Paul Van Bendegem (Belgium, born 1953)
- Jean Piaget
- Jean Van Heijenoort (France/US, 1912–1986)
- Jean-François Lyotard
- Jean-François Lyotard[37]
- Jean-Jacques Rousseau
- Jean-Jacques Rousseau (1712–1788)
- Jean-Luc Marion
- Jean-Luc Nancy[41]
- Jean-Marie Guyau
- Jean-Paul Sartre
- Jean-Paul Sartre (1905–1980)
- Jean-Yves Béziau (Switzerland, born 1965)
- Jean-Yves Girard (France, born 1947)
- Jedaiah ben Abraham Bedersi
- Jeff Paris (UK, born 1944)
- Jeffrey A. Barrett
- Jeffrey Sachs
- Jeffrey Stout
- Jeremy Bentham
- Jeremy Bentham (1748–1832)
- Jeremy Bentham[8]
- Jeroen Groenendijk
- Jeroen Groenendijk (Netherlands, 1949–2023)
- Jerome Bruner
- Jerrold Katz
- Jerry Fodor
- Jerzy Łoś (Poland, 1920–1998)
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- Joachim Jungius (Germany, 1587–1657)
- Joachim Lambek (Canada, 1922–2014)
- Jodi Dean[22]
- Joe L. Kincheloe
- Johan van Benthem (Netherlands, born 1949)
- Johann Albert Fabricius
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- Johann Georg Hamann
- Johann Georg Sulzer
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- Johann Gottlieb Fichte (1762–1814)
- Johann Heinrich Lambert (France/Germany, 1728–1777)
- John Arthur
- John Austin
- John Austin[17]
- John B. Watson
- John Brown[5]: 502
- John Cage
- John Calvin (1509–1564)
- John Collier[20]
- John Corcoran (US, 1937–2021)
- John Daniel Wild
- John Dewey
- John Dewey (1859–1952)
- John Dumbleton (England, died c. 1349)
- John Duns Scotus
- John Duns Scotus (UK, France, c. 1266–1308)
- John Dupré
- John E. Murdoch
- John Earman
- John Etchemendy
- John Etchemendy (US, born 1952)
- John Finnis
- John Fiske[26]
- John Gay[5]: 179–181
- John Gray (1948–)
- John Harsanyi
- John Harsanyi[30]
- John Hawthorne
- John Henry Newman (1801–1890)
- John Henry Newman (1801–1890) (see Grammar of Assent)
- John Hick
- John Hospers
- John Howard Yoder
- John Joseph O'Connor
- John L. O'Sullivan[5]: 384–385
- John Lane Bell (UK and Canada, born 1945)
- John Lennox
- John Locke
- John Locke (1632–1704)
- John M. Cooper
- John Mair (Scotland, 1467–1550)
- John McDowell
- John McTaggart
- John Milton
- John Neal[5]: 367–369
- John O'Neill, University of Manchester
- John of St. Thomas
- John of St. Thomas (John Poinsot)
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- John of St. Thomas/John Poinsot (Portugal/Spain, 1589–1644)
- John Pagus (France, fl. 1220–1229)
- John Passmore
- John Paul II
- John Peckham
- John Perry
- John Peters Humphrey - author of UN Declaration of Universal Human Rights
- John Philoponus
- John Polkinghorne
- John R. Steel (US, born 1948)
- John Ralston Saul
- John Rawls
- John Rawls (1921–2002)
- John Roberts (philosopher)
- John Rodman, Claremont College
- John Ruskin
- John Scotus Eriugena
- John Searle
- John Shelby Spong
- John Stevens Cabot Abbott
- John Stuart Mill
- John Stuart Mill (1806–1873)
- John Stuart Mill (England, 1806–1873)
- John Stuart Mill[25]
- John Venn (England, 1834–1923)
- John von Neumann (Hungary, US, 1903–1957)
- John Wippel
- John Wisdom
- John Woods (Canada, 1937–2024)
- John Worrall
- John Zerzan
- Jon Barwise (US, 1942–2000)
- Jon Michael Dunn (US, 1941–2021)
- Jonathan Baron[37]
- Jonathan Bennett
- Jonathan Dancy
- Jonathan Edwards
- Jonathan Glover
- José Faur
- José Medina
- José Ortega y Gasset
- Joseph Bankman[35]
- Joseph ben Abraham
- Joseph de Maistre
- Joseph de Maistre (1753–1821)
- Joseph Diaz Gergonne (France, 1771–1859)
- Joseph Fins
- Joseph Fletcher
- Joseph ibn Tzaddik
- Joseph Kleutgen
- Joseph Kosuth
- Joseph Owens (Redemptorist)
- Joseph Priestley
- Joseph Priestley[16]
- Joseph Raz
- Joseph Schumpeter
- Joseph Solomon Delmedigo
- Joshua Greene
- Joxe Azurmendi
- Joxe Azurmendi (1941–)
- Józef Maria Bocheński (Poland, 1902–1995)
- Juan Donoso Cortés
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- Jurij Moskvitin
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- K
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- Karl-Otto Apel
- Karol Wojtyła
- Katarzyna de Lazari-Radek[47]
- Kazimierz Ajdukiewicz (Poland, 1890–1963)
- Kazimierz Twardowski (Poland, 1866–1938)
- Keith DeRose
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- Ken Taylor
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- Kent Bach
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- Kundakunda
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- L
- L. T. F. Gamut (collective pseudonym used by a group of Dutch logicians, fl. 1980s–1990s)
- L. W. Sumner[59]
- L.A. Paul
- Lao Tzu
- Larry Laudan
- Larry Temkin
- Late modern
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- Laurence Bonjour
- Lauri Ingman
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- Lawrence Krauss[44]
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- Leopold Kronecker (Germany, 1823–1891)
- Leopold Löwenheim (Germany, 1878–1957)
- Leslie Stephen
- Leslie Stephen[5]: 535–538
- Leszek Kołakowski
- Leucippus
- Lewis Carroll (UK, 1832–1898)
- Lewis H. Morgan
- Lewis White Beck
- Lionel Robbins[5]: 484–486
- Liu Xie
- Living
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- Lorraine Code
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- Luitzen Egbertus Jan Brouwer (Netherlands, 1881–1966)
- Lynne Tirrell
- Lysander Spooner
- M
- Maarten Boudry
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- Matthew Foreman (US, born 1957)
- Maurice Blanchot
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- Mazdak
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- Michael A. E. Dummett (UK, 1925–2011)
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- N
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- Numenius
- O
- Octave Mirbeau
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- Oscar Horta
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- Otto Bauer (1881–1938)
- Otto Kirchheimer
- Otto Neurath
- Otto Weininger
- Owen Flanagan
- P
- P. F. Strawson
- Pakṣilasvāmin Vātsyāyana wrote the first known commentary on Goutama's Nyaya Sutras (5th century CE)
- Pamela Sue Anderson
- Paolo Barbò da Soncino
- Paolo da Pergola (Italy, died 1455)
- Parmenides
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- Paul Benacerraf
- Paul Benacerraf (US, 1931-2025)
- Paul Bernays (Switzerland, 1888–1977)
- Paul Boghossian
- Paul Churchland
- Paul Feyerabend
- Paul Grice
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- Paul Hoyningen-Huene
- Paul Janet
- Paul Joseph Cohen (US, 1934–2007)
- Paul Lorenzen
- Paul Lorenzen (Germany, 1915–1994)
- Paul of Venice (Italy, 1368–1428)
- Paul of Venice (Italy, 1369–1429)
- Paul Oppenheim
- Paul R. Ehrlich
- Paul Shepard, Claremont McKenna College
- Paul Tillich
- Paul Virilio
- Paul W. Taylor
- Paul Ziff
- Paulo Freire
- Pavel Florensky
- Pavel Materna (Czech Republic, born 1930)
- Pavel Tichý (Czechoslovakia, New Zealand, 1936–1994)
- Peg Birmingham
- Pekka Himanen
- Penelope Maddy (US, born 1950)
- Per Lindström (Sweden, 1936–2009)
- Per Martin-Löf (Sweden, born 1942)
- Peregrine Bingham the Younger[5]: 57
- Peter Abelard
- Peter Abelard (France, 1079–1142)
- Peter Achinstein
- Peter B. Andrews (US, 1938–2025)
- Peter Carruthers
- Peter D. Klein
- Peter F. Strawson
- Peter Geach
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- Peter Lamborn Wilson
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- Peter Medawar
- Peter of Spain (13th century, usually assumed to be Pope John XXI)
- Peter of Spain (13th century)
- Peter Pagin
- Peter Railton
- Peter Singer
- Peter Singer, Princeton University
- Peter Singer[57]
- Peter Sloterdijk
- Peter Unger
- Peter van Inwagen
- Petr Hájek (Czech Republic, 1941–2016)
- Petrus Aureoli
- Petrus de Ibernia
- Petrus Ramus (France, 1515–1572)
- Philip Doddridge
- Philip Jourdain (UK, 1879–1919)
- Philip Kitcher
- Philip Pettit
- Philip the Chancellor
- Philip Wicksteed
- Philippa Foot
- Philippe Lacoue-Labarthe[35]
- Philippe Van Parijs
- Phillip H. Wiebe
- Philo of Alexandria
- Philo the Dialectician (Greece, 4th–3rd century BC)
- Piergiorgio Odifreddi (Italy, born 1950)
- Pierre Bayle
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- Pierre-Joseph Proudhon
- Pierre-Joseph Proudhon (1809–1865)
- Plato
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- Pliny the Younger (63–113 CE)
- Plotinus
- Polybius
- Polybius (c.200-118 BCE)
- Porphyry
- Porphyry (c. 234–c. 305)
- Prabhat Ranjan Sarkar
- Prabhat Ranjan Sarkar (1921–1990)
- Proclus
- Prodicus
- Protagoras
- Pseudo-Dionysius the Areopagite
- Pyotr Novikov (Russia/Soviet Union, 1901–1975)
- Pyrrho
- Pythagoras
- Q
- Quentin Meillassoux
- Quentin Smith
- Quintilian
- R
- R. B. Braithwaite
- R. Edward Freeman
- R. G. Collingwood
- R. G. Frey
- R. M. Hare
- R. M. Hare[29]
- Rabindranath Tagore (1861–1941)
- Radhakamal Mukerjee
- Rae Helen Langton
- Raghunatha Siromani (India, 1470s–1550s)
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- Ramanuja
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- Randy Cohen
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- Raphael M. Robinson (US, 1911–1995)
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- Raymond Aron
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- Reginald Garrigou-Lagrange
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- Reginald Garrigou-Lagrange, OP
- Reinhold Niebuhr
- Renaissance and early modern
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- René Descartes
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- René Girard
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- René Guénon
- René Guénon (1886–1951)
- Reuben Louis Goodstein (England, 1912–1985)
- Rey Chow[20]
- Ricardo Rozzi, University of North Texas and Omora Ethnobotanical Park (Universidad de Magallanes & IEB, Chile)
- Richard Boyd
- Richard Brandt[27]
- Richard Brinkley (England, died c. 1379)
- Richard Clyde Taylor
- Richard Clyde Taylor[1][2][3]
- Richard Cumberland[5]: 104–106
- Richard Ferrybridge (England, 14th century)
- Richard Fumerton
- Richard Hildreth[5]: 234–240
- Richard Hönigswald
- Richard Hooker (1554–1600)
- Richard Jeffrey (US, 1926–2002)
- Richard Kilvington (England, c. 1305–1361)
- Richard Layard[46]
- Richard M. Weaver
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- Richard Montague
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- Richard of Saint Victor
- Richard Price
- Richard Rorty
- Richard Rorty (1931–2007)
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- Richard Swinburne
- Richard Swineshead (England, fl. c. 1340–1354)
- Richard Sylvan (originally published as Richard Routley)
- Richard Sylvan, born Richard Routley (New Zealand, 1935–1996)
- Richard the Sophister (fl. late 13th century)
- Richard Whately (England, 1787–1863)
- Richard Wollheim
- Richard Yetter Chappell [39]
- Right Hegelians
- Robert Anton Wilson
- Robert Audi
- Robert Bellarmine
- Robert Bellarmine (1542–1621)
- Robert Brandom
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- Robert D. Putnam
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- Robert Filmer
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- Robert K. Merton
- Robert Kilwardby (England, c. 1215–1279)
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- Robert Maximilian de Gaynesford
- Robert Merrihew Adams
- Robert Nozick
- Robert Nozick (1938–2002)
- Robert P. George
- Robert Rynasiewicz
- Robert S. Hartman
- Robert S. Hartman (Germany/US, 1910–1973)
- Robert Stalnaker
- Robert W. Cox
- Robert Wright[61]
- Roberto Esposito
- Roberto Mangabeira Unger
- Roberto Mangabeira Unger (1947–)
- Roberto Torretti
- Robin Attfield
- Robin Gandy (UK, 1919–1995)
- Roderick Chisholm
- Rodolphus Agricola (Germany, 1443/1444–1485)
- Roger Bacon
- Roger Bacon[3][4]
- Roger Chao
- Roger Crisp
- Roger Scruton
- Roger Scruton (1944–2020)
- Roland Barthes
- Roland Barthes[17]
- Roland Fraïssé (France, 1920–2008)
- Rolf Schock (US, Sweden, 1933–1986)
- Roman Ingarden
- Ron McClamrock
- Ronald Dworkin
- Ronald Dworkin (1931–2013)
- Ronald Giere
- Ronald Jensen (US, Europe, 1936–2025)
- Roscellinus
- Ross Cameron
- Roy Bhaskar
- Roy Harrod[5]: 212–213
- Rózsa Péter (Hungary, 1905–1977)
- Rudolf Arnheim
- Rudolf Carnap
- Rudolf Carnap (Germany, 1891–1970)
- Rudolf Christoph Eucken
- Rudolf Rocker (1873–1958)
- Rudolf Steiner
- Ruhollah Khomeini
- Ruhollah Khomeini (1906–1989)
- Rushworth Kidder
- Russ Shafer-Landau
- Russell Kirk
- Russell Kirk (1918–1994)
- Ryan Osmun (florence, 1984-present)
- S
- S. Barry Cooper (UK, 1943–2015)
- S. Morris Engel
- Saadia Gaon
- Saharon Shelah (Israel, born 1945)
- Sahotra Sarkar
- Said Nursi
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- Saint Robert Bellarmine, S.J.
- Saint Thomas Aquinas
- Saint Thomas Aquinas, OP
- Salomon Maimon
- Sam Bankman-Fried[36]
- Sam Harris
- Samantha Brennan
- Samuel Bailey
- Samuel Bailey[18]
- Samuel Edward Konkin III
- Samuel Eilenberg (Poland, 1913–1998)
- Samuel Guttenplan
- Samuel ibn Tibbon
- Samuel P. Huntington (1927–2008)
- Samuel Scheffler
- Samuel Taylor Coleridge
- Samuel Taylor Coleridge (1772–1834)
- Samuel von Pufendorf
- Sana Ahmad
- Saul Kripke
- Saul Kripke (US, 1940–2022)
- Saunders Mac Lane (US, 1909–2005)
- Sayyid Qutb
- Sayyid Qutb (1906–1966)
- Scott Soames
- Scott Sumner[58]
- Sedulius Scottus (Ireland/France, fl. 840–860)
- Semyon Frank
- Serenella Iovino
- Serge Moscovici
- Sergei Adian (Russia/Soviet Union/Armenia, 1931–2020)
- Sergei Bulgakov
- Sextus Empiricus
- Seyla Benhabib
- Seyyed Hossein Nasr
- Shadworth Hodgson
- Shannon Sullivan
- Shaun Gallagher
- Shelbi Nahwilet Meissner
- Shelly Kagan
- Shelly Kagan[5]: 300–301
- Shem-Tov ibn Falaquera
- Sherrilyn Roush
- Shulamith Firestone
- Siegfried Gottwald (Germany, 1943–2015)
- Siegfried Kracauer
- Simcha Zissel Ziv
- Simon Critchley
- Simplicius of Cilicia
- Simplicius of Cilicia (Turkey/Iran, c. 490–c. 560)
- Sir Francis Bacon
- Sir Karl Popper
- Sir Syed Ahmad Khan (1818–1898)
- Siri Hustvedt
- Slavoj Žižek
- Slavoj Žižek (1947–)
- Soame Jenyns[9]
- Socrates
- Socrates (470–399 BCE)
- Sojourner Truth
- Sol Garfunkel (US, born 1943)
- Solomon
- Solomon Feferman (US, 1928–2016)
- Solomon ibn Gabirol
- Solomon Passy (Bulgaria, born 1956)
- Søren Kierkegaard
- Speusippus
- Sri Aurobindo
- St. Thomas Aquinas
- Stanisław Jaśkowski (Poland, 1906–1965)
- Stanisław Leśniewski (Poland, 1886–1939)
- Stanley Cavell
- Stanley Grenz
- Stanley Hauerwas
- Stathis Psillos
- Stephen Bronner
- Stephen Cole Kleene (US, 1909–1994)
- Stephen Greenblatt
- Stephen Hetherington
- Stephen Laurence
- Stephen Neale
- Stephen R. L. Clark, University of Liverpool
- Stephen R.L. Clark
- Stephen Schiffer
- Stephen Stich
- Stephen Toulmin
- Stephen Yablo
- Steven Pinker
- Steven Pinker[54]
- Stewart Shapiro (US, born 1951)
- Stobaeus
- Stuart Hall
- Stuart Rachels[55]
- Stuart Wilde
- Sun Tzu
- Sun Yat-sen
- Sun Yat-sen (1866–1925)
- Susanne Langer
- Susanne Sreedhar
- Sut Jhally
- Swami Vivekananda
- Swami Vivekananda (1863-1903)
- Sydney Shoemaker
- Syrianus
- T
- T. M. Scanlon
- Tad Schmaltz
- Tadeusz Czeżowski (Poland, 1889–1981)
- Tadeusz Kotarbiński
- Tadeusz Kotarbiński (Poland, 1886–1981)
- Taketani Mitsuo
- Takis Fotopoulos
- Talcott Parsons
- Tamar Gendler
- Tan Sitong
- Tariq Ali
- Tenzin Gyatso, the 14th Dalai Lama
- Terence Parsons
- Tess Posner
- Thales
- Thales Of Miletus (Turkey, 626 BC – 545 BC)
- Theodor Adorno
- Theodor Adorno (1903–1969)
- Theodor Herzl
- Theodor W. Adorno
- Theodor Zwinger
- Theodore Sider
- Théodore Simon Jouffroy
- Theodore Slaman (US, born 1954)
- Theodorus the Atheist
- Theophrastus
- Theophrastus (Greece, 371–c. 287 BC)
- Thierry Coquand (France, born 1961)
- Thierry of Chartres
- Thiruvalluvar
- Thomas Aquinas
- Thomas Aquinas (Italy/France, 1225–1274)
- Thomas Aquinas, OP (1225–1274)
- Thomas Baldwin
- Thomas Bayes
- Thomas Berry
- Thomas Bradwardine (England, c. 1290–26 August 1349)
- Thomas Brown
- Thomas Cajetan
- Thomas Cajetan, OP (1469–1534)
- Thomas Carlyle
- Thomas Carlyle (1795–1881)
- Thomas Cooper[5]: 100–103
- Thomas Fowler[5]: 172
- Thomas Henry Huxley
- Thomas Hill Green
- Thomas Hill Green (1836–1882)
- Thomas Hobbes
- Thomas Hobbes (1588–1679)
- Thomas Huxley
- Thomas Jefferson (1743–1826)
- Thomas Kuhn
- Thomas Metzinger
- Thomas More
- Thomas Muntzer (1490–1525)
- Thomas Nagel
- Thomas Nagel (1937–)
- Thomas Paine
- Thomas Paine (1737–1809)
- Thomas Perronet Thompson[5]: 545–547
- Thomas Reid
- Thomas Robert Malthus (1766–1834)
- Thomas Rutherforth[13]
- Thomas Southwood Smith[5]: 525–527
- Thomas Sowell
- Thoralf Skolem (Norway 1887–1963)
- Thorstein Veblen (1857–1929)
- Thucydides
- Tim Maudlin
- Timon of Phlius
- Timothy Leary
- Timothy Luke
- Timothy Morton
- Timothy Sprigge
- Timothy Sprigge[34]
- Timothy Williamson
- Toby Ord[48]
- Todd May[39]
- Tom Beauchamp
- Tom Regan
- Tom Regan, North Carolina State University
- Tommy J. Curry
- Torbjörn Tännsjö[60]
- Trenton Merricks
- Trinh T. Minh-ha
- Tyagaraja
- Tyler Burge
- Tyler Cowen[40]
- U
- U to Z
- Udayana, author of Nyayakusumanjali (rational theology to prove the existence of God using logic) (India, 10th century)
- Udyotakara (India, c. 6th century CE)
- Ullin Place
- Uma Narayan
- Umar ibn Al-Khattab
- Umberto Eco
- Umberto Eco[25]
- V
- Vācaspati Miśra
- Vāchaspati Misra
- Valentin Goranko (Bulgaria/Sweden, born 1959)
- Vallabha
- Vallabhbhai Patel (1875–1950)
- Vasily Rozanov
- Veda Vyasa
- Victor Cousin
- Victor Gollancz
- Vidyaranya
- Viktor Shklovsky
- Vilfredo Pareto
- Vilfredo Pareto (1848–1923)
- Vinayak Damodar Savarkar
- Virgil Aldrich
- Vissarion Belinsky
- Vladimir Lenin
- Vladimir Lenin (1870–1924)
- Vladimir Solovyov
- Vladimir Uspensky (Soviet Union/Russia, 1930–2018)
- Voltaire
- Voltaire (1694–1778)
- Vyasatirtha
- W
- W. D. Ross
- W. Hugh Woodin (US, born 1955)
- W.V. Quine
- W.V.O. Quine
- Walter Benjamin
- Walter Benjamin (1892–1940)
- Walter Burley
- Walter Burley (England, c. 1275–1344/5)
- Walter Mignolo
- Walter Pater
- Walter Pitts (US, 1923–1969)
- Walter Terence Stace
- Ward Jones
- Wau Holland
- Werner Heisenberg
- Wesley C. Salmon
- Wesley J. Smith
- Wesley Newcomb Hohfeld
- Wesley Wildman
- Whitall Perry
- Wilfrid Sellars
- Wilhelm Ackermann (Germany, 1896–1962)
- Wilhelm Dilthey
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