This list of thinkers is a placeholder for future visualizations and advanced search interfaces for our thinker database. Use the searchbox to the left to perform searches over the entire InPhO knowledge base.
1776 total Thinkers in database.
- Firmin Abauzit
- Nicola Abbagnano
- Muhammad Abduh
- Jacob Friedrich von Abel
- Peter Abelard
- John Abercrombie
- Abhinavagupta
- Johann Heinrich Abicht
- Abner of Burgos
- Isaac ben Judah Abravanel
- Judah ben Isaac Abravanel
- Alessandro Achillini
- Uriel Acosta
- H. B. Acton
- Adam Parvipontanus
- Marilyn McCord Adams
- Robert Adams
- Robert Adamson
- Adelard of Bath
- Mortimer Adler
- Theodor Adorno
- Aedesius
- Aenesidemus
- Sediq Afghan
- Jamal al-Din al-Afghani
- Giorgio Agamben
- Rodolphus Agricola
- Agrippa the Sceptic
- Heinrich Cornelius Agrippa
- Pierre d'Ailly
- Kazimierz Ajdukiewicz
- Konstantin Sergeyevich Aksakov
- Alain de Lille
- Albert of Saxony
- Leone Battista Alberti
- Albertus Magnus
- Albinus
- Joseph Albo
- Rogers Albritton
- Alcibiades
- Alcinous
- Alcmaeon
- Virgil Aldrich
- Yohanan ben Isaac Alemanno
- Aleksandr Danilovich Aleksandrov
- Alexander of Aphrodisias
- Alexander of Hales
- Gerda Alexander
- Samuel Alexander
- Robert Alexy
- Francesco Algarotti
- Dante Alighieri
- Archibald Alison
- Henry Allison
- William Alston
- Louis Althusser
- Robert Alyngton
- Bhimrao Ambedkar
- Ambrose
- Henri-Frédéric Amiel
- Abu'l Hasan Muhammad Ibn Yusuf al-'Amiri
- Ammonius Hermiae
- Ammonius Saccas
- Anton Wilhelm Amo
- Anacharsis
- Anandavardhana
- Anaxagoras
- Anaxarchus
- Anaxilaus
- Anaximander
- Anaximenes of Miletus
- Alan Ross Anderson
- John Anderson
- Andronicus of Rhodes
- Anniceris
- G. E. M. Anscombe
- Saint Anselm
- Antiochus of Ascalon
- Antiphon
- Antisthenes
- Karl-Otto Apel
- Apollonius of Tyana
- Anthony Appiah
- Apuleius
- Saint Thomas Aquinas
- Isaac ben Moses Arama
- Arcesilaus
- Archimedes
- Archytas
- Roberto Ardigo
- Hannah Arendt
- Aristides
- Aristippus the Elder of Cyrene
- Ariston of Chios
- Aristotle
- Aristoxenus
- Arius
- Jacobus Arminius
- David Malet Armstrong
- Antoine Arnauld
- Raymond Aron
- Kenneth Arrow
- Asclepiades
- Valentin Ferdinandovich Asmus
- Aspasius
- Georg Anton Friedrich Ast
- Mary Astell
- Athanasius of Alexandria
- Titus Pomponius Atticus
- Robert Audi
- Augustine of Hippo
- Marcus Aurelius
- Peter Aureol
- Sri Aurobindo
- John Austin
- John Langshaw Austin
- Richard Avenarius
- Averroes
- Avicenna
- Alfred Jules Ayer
- Pierre Hyacinthe Azais
- Franz Xaver von Baader
- Charles Babbage
- Gaston Bachelard
- Francis Bacon
- Roger Bacon
- Alain Badiou
- Hibat Allah Abu'l-Barakat al-Baghdaadi
- Annette Baier
- Kurt Baier
- Alexander Bain
- Mikhail Bakhtin
- Mikhail Bakunin
- James Mark Baldwin
- John Balguy
- Étienne Balibar
- Pierre-Simon Ballanche
- Domingo Báñez
- Abraham bar Hiyya Ha-Nasi
- Yehoshua Bar-Hillel
- Christoph Gottfried Bardili
- Stephen Barker
- Jonathan Barnes
- Brian Barry
- Karl Barth
- Jules Barthélemy-Saint-Hilaire
- Roland Barthes
- Bartolus de Saxoferrato
- Jon Barwise
- Jacques Barzun
- Basilides
- Sébastien Basson
- Georges Bataille
- Jean Baudrillard
- Bruno Bauer
- David Baumgardt
- Alexander Gottlieb Baumgarten
- Pierre Bayle
- Monroe Beardsley
- James Beattie
- Jean Beaufret
- Cesare
- Jacob Sigismund Beck
- William Bechtel
- Oskar Becker
- Hamdija Begovic
- Vissarion Belinsky
- Nuel Belnap
- Paul Benacerraf
- Julien Benda
- Friedrich Eduard Beneke
- Walter Benjamin
- Jonathan Bennett
- Geoffrey Bennington
- Jeremy Bentham
- Richard Bentley
- Nikolai Berdyaev
- Gustav Bergmann
- Henri Bergson
- George Berkeley
- Isaiah Berlin
- Bernard of Chartres
- Bernard of Clairvaux
- Bernard Silvestris
- François Bernier
- Eduard Bernstein
- Basil Bessarion
- Homi Bhabha
- Bhartrhari
- Roy Bhaskar
- Gabriel Biel
- Hugh Binning
- Harry Binswanger
- Nathan Birnbaum
- Max Black
- Simon Blackburn
- William Blackstone
- Hugh Blair
- Maurice Blanchot
- Brand Blanshard
- Blasius of Parma
- David Blitz
- Ernst Bloch
- Ned Block
- Maurice Blondel
- Benjamin Paul Blood
- Allan Bloom
- Gaius Blossius
- Hermann Blumenau
- Norberto Bobbio
- Jozef Maria Bochenski
- Jean Bodin
- Anicius Manlius Severinus Boethius
- Boëthius of Dacia
- Alexander Bogdanov
- Jakob Boehme
- Niels Bohr
- Samuel Bold
- Ludwig Boltzmann
- Bernard Bolzano
- Louis Gabriel Ambroise de Bonald
- Bonaventure
- Dietrich Bonhoeffer
- Laurence BonJour
- Charles Bonnet
- John Elof Boodin
- George Boole
- George Boolos
- Bernard Bosanquet
- Rudjer Boscovich
- Pierre Bourdieu
- Emile Boutroux
- Oets Kolk Bouwsma
- Borden Parker Bowne
- Robert Boyle
- Francis Herbert Bradley
- Thomas Bradwardine
- Richard-Bevan Braithwaite
- Robert Brandom
- Richard Brandt
- Franz Brentano
- Percy Williams Bridgman
- Edgar Brightman
- Jean Anthelme Brillat-Savarin
- Richard Brinkley
- Radulphus Brito
- Charlie Dunbar Broad
- Stephen Bronner
- Luitzen Egbertus Jan Brouwer
- Thomas Brown
- Bryn Browne
- Peter Browne
- Thomas Browne
- Orestes Brownson
- Constantin Brunner
- Emil Brunner
- Giordano Bruno
- Leon Brunschvicg
- James Bryce
- Martin Buber
- Justus Buchler
- Ludwig Buechner
- Malcolm Budd
- Buddhaghosa
- Claude Buffier
- Georges-Louis Leclerc
- Sergei Nikolaevich Bulgakov
- Rudolf Bultmann
- Mario Bunge
- Jacob Burckhardt
- Tyler Burge
- Jean Buridan
- Edmund Burke
- Walter Burley
- John Burnheim
- Myles Frederic Burnyeat
- Richard Burthogge
- Panayot Butchvarov
- Joseph Butler
- Judith Butler
- Samuel Butler
- Pierre Jean George Cabanis
- Amílcar Cabral
- Cai Yuanpei
- Edward Caird
- Thomas Cajetan
- Calcidius
- Mary Whiton Calkins
- Callicles
- John Calvin
- Tommaso Campanella
- George Campbell
- John Campbell
- Norman Robert Campbell
- Albert Camus
- Georges Canguilhem
- Georg Cantor
- Johannes Capreolus
- John D. Caputo
- Gerolamo Cardano
- Thomas Carlyle
- Gershom Carmichael
- Rudolf Carnap
- Carneades
- Lewis Carroll
- Nancy Cartwright
- Paul Carus
- Ernst Cassirer
- Hector-Neri Castañeda
- Cornelius Castoriadis
- Carlo Cattaneo
- Cavalcante de' Cavalcanti
- Stanley Cavell
- Margaret Cavendish
- Cebes
- Celsus of Alexandria
- Michel de Certeau
- Andrea Cesalpino
- Petr Iakovlevich Chaadev
- Chaerephon
- David Chalmers
- Heinrich Moritz Chalybaeus
- Timothy Chambers
- Rafe Champion
- Chanakya
- Candrakirti
- Zhang Xuecheng
- Chang Tsai
- Walter Charleton
- Pierre Charron
- Emile Auguste Chartier
- Walter Chatton
- Haridas Chaudhuri
- Ch'en Hsien-chang
- Cheng Hao
- Cheng Hsuan
- Cheng Yi
- Nikolai Chernyshevsky
- Chia Yi
- Chiao Hung
- Ch'ien Mu
- Chih Tun
- William Chillingworth
- Roderick Chisholm
- Noam Chomsky
- Tasan Chông Yagyong
- Chou Tun-Yi
- Christine de Pizan
- Andrea Christofidou
- Chrysanthius
- Chrysippus
- Manuel Chrysoloras
- Alonzo Church
- Patricia Churchland
- Paul Churchland
- Leon Chwistek
- Cicero
- August Cieszkowski
- Hélène Cixous
- Clarembald of Arras
- Andy Clark
- Samuel Clarke
- Johannes Clauberg
- Cleanthes
- Clement of Alexandria
- Cleobulus
- Cleomedes
- William Kingdon Clifford
- Catherine Trotter Cockburn
- David Cockburn
- G.A. Cohen
- Hermann Cohen
- L. Jonathan Cohen
- Samuel Taylor Coleridge
- Lucio Colletti
- Arthur Collier
- R. G. Collingwood
- Anthony Collins
- John Comenius
- Auguste Comte
- André Comte-Sponville
- Marcel Conche
- Gerhard Anna Concic-Kaucic
- Etienne Bonnot de Condillac
- Marquis de Condorcet
- Confucius
- Benjamin Constant
- Lady Anne Finch Conway
- Josephus Flavius Cook
- Ananda Kentish Coomaraswamy
- Nicolaus Copernicus
- Frederick Copleston
- Geraud de Cordemoy
- Hans Cornelius
- Antoine Augustin Cournot
- Victor Cousin
- Louis Couturat
- Chris Cowan
- William Lane Craig
- Johann Ulrich von Cramer
- Crantor
- Crates of Thebes
- William Crathorn
- Cratylus of Athens
- James Edwin Creighton
- Johannes Crellius
- Hasdai Crescas
- Benedetto Croce
- Jean-Pierre de Crousaz
- Christian August Crusius
- Ralph Cudworth
- Nathaniel Culverwel
- Richard Cumberland
- Cyril of Alexandria
- Tadeusz Czezowski
- Heinrich Czolbe
- Jean le Rond d'Alembert
- Damascius
- Peter Damian
- Nikolay Danilevsky
- Arthur Danto
- Charles Darwin
- David of Dinant
- David the Invincible
- Donald Davidson
- Michael Davis
- Jalal al-Din al-Dawani
- Simone de Beauvoir
- Bruno de Finetti
- Joseph de Maistre
- Paul de Man
- Augustus De Morgan
- Francesco De Sanctis
- Emerich de Vattel
- Guy Debord
- Richard Dedekind
- Gilles Deleuze
- Galvano Della Volpe
- Elijah Delmedigo
- Joseph Solomon Delmedigo
- Demetrius the Cynic
- Democritus
- Daniel Dennett
- Denys the Carthusian
- Jacques Derrida
- John Theophilus Desaguliers
- René Descartes
- Vincent Descombes
- Robert Desgabets
- Paul Deussen
- John Dewey
- Dharmakirti
- Diagoras
- Sousa Dias
- Albert Venn Dicey
- Denis Diderot
- Dietrich of Freiberg
- Kenelm Digby
- Dignaga
- Wilhelm Dilthey
- Hugo Dingler
- Diodorus Cronos
- Diogenes Laertius
- Diogenes Apolloniates
- Diogenes of Oenoanda
- Diogenes the Cynic of Sinope
- Humphry Ditton
- Dogen Zenji
- Daniel Dombrowski
- Dong Zhongshu
- Keith Donnellan
- Herman Dooyeweerd
- Elliot N. Dorff
- Fyodor Dostoevsky
- Fred Dretske
- Hubert Dreyfus
- Hans Adolf Eduard Driesch
- Emil du Bois-Reymond
- Émilie du Châtelet
- Guillaume du Vair
- Curt Ducasse
- Pierre Duhem
- Eugen Duehring
- Michael Dummett
- Duns Scotus
- Profiat Duran
- Simeon ben Zemah Duran
- Durandus of St. Pourçain
- Émile Durkheim
- Ronald Dworkin
- Miroslaw Dzielski
- Julius Ebbinghaus
- Johann Augustus Eberhard
- Meister Eckhart
- Umberto Eco
- Dorothy Edgington
- Jonathan Edwards
- Paul Edwards
- Christian von Ehrenfels
- Albert Einstein
- Mircea Eliade
- Elias
- George Eliot
- Elisabeth of Bohemia
- Jacques Ellul
- Jon Elster
- Ralph Waldo Emerson
- Empedocles
- Friedrich Engels
- Epicharmus
- Epictetus
- Epicurus
- Epimenides
- Desiderius Erasmus
- Johannes Scotus Erigina
- Eubulides of Miletus
- Rudolf Christoph Eucken
- Euclid of Alexandria
- Euclid of Megara
- Eudoxus of Cnidus
- Eusebius of Caesarea
- Gareth Evans
- Julius Evola
- Emil Fackenheim
- Thome H. Fang
- Frantz Fanon
- Al-Farabi
- Michelangelo Fardella
- Austin Marsden Farrer
- Favorinus
- Fazang
- Gustav Fechner
- Herbert Feigl
- Joel Feinberg
- François de Salignac de la Mothe-Fénelon
- Feng Youlan
- Ernest Fenollosa
- Adam Ferguson
- Giuseppe Ferrari
- Jose Ferrater-Mora
- James Frederick Ferrier
- Ludwig Feuerbach
- Paul Feyerabend
- Johann Gottlieb Fichte
- Immanuel Hermann Fichte
- Marsilio Ficino
- Hartry Field
- Robert Filmer
- John Finnis
- Kuno Fischer
- John Fiske
- Franciszek Fiszer
- Antony Flew
- Pavel Aleksandrovich Florenskii
- Georges Florovsky
- Robert Fludd
- Vilém Flusser
- Jerry Fodor
- Robert J. Fogelin
- Dagfinn Føllesdal
- Pedro da Fonseca
- Bernard le Bovier de Fontenelle
- Philippa Foot
- David Fordyce
- Eckart Forster
- Michel Foucault
- Simon Foucher
- Charles Fourier
- Francis of Assisi
- Francis of Marchia
- Francis of Meyronnes
- Jerome Frank
- Philipp Frank
- Semën Liudvigovich Frank
- William K. Frankena
- Harry Gordon Frankfurt
- Benjamin Franklin
- Oliver Shewell Franks
- Michael Frede
- Gottlob Frege
- Hans Frei
- Jakob Friedrich Fries
- Sigmund Freud
- Hans Freyer
- Northrop Frye
- Fujiwara Seika
- Lon L. Fuller
- Casey Fulton
- Nikolai Fyodorovich Fyodorov
- Gadadhara Bhattacharya
- Hans-Georg Gadamer
- Gaius
- Galen
- Galileo Galilei
- Mahatma Gandhi
- Gangeśa
- Martin Gardner
- Réginald Garrigou-Lagrange
- Pierre Gassendi
- Aksapada Gautama
- Nārāyana Guru
- Buddha
- David Gauthier
- John Gay
- Peter Geach
- Ernest Gellner
- Geminus
- Gennadius Scholarius
- Giovanni Gentile
- Gerhard Gentzen
- George of Trebizond
- Gerard of Cremona
- Gerard of Odo
- Alexander Gerard
- Gerbert of Aurillac
- Giacinto Cardinal Sigismondo Gerdil
- Jean Gerson
- Gersonides
- Bernard Gert
- Edmund Gettier
- Arnold Geulincx
- Raymond Geuss
- Alan Gewirth
- Al-Ghazali
- Allan Gibbard
- Otto von Gierke
- Bishop Gilbert of Poitiers
- Giles of Rome
- Neil Gillman
- Charlotte Perkins Gilman
- Étienne Gilson
- Asher Ginsberg
- Vincenzo Gioberti
- René Girard
- Thomas Gisbourne
- Joseph Glanvill
- Ernst von Glasersfeld
- Jonathan Glover
- Clark Glymour
- Arthur de Gobineau
- Rudolph Goclenius
- Kurt Goedel
- Godfrey of Fontaines
- William Godwin
- Johann Wolfgang von Goethe
- Alvin Ira Goldman
- Lucien Goldmann
- Gongsun Longzi
- Nelson Goodman
- Gorgias
- Wawrzyniec Grzymala Goslicki
- Baltasar Gracián y Morales
- Antonio Gramsci
- Guido Grandi
- D. Granosalis
- George Grant
- Richard Grathoff
- Clare W. Graves
- John Gray
- A. C. Grayling
- Celia Green
- Thomas Hill Green
- Pope Gregory
- Gregory of Nyssa
- Gregory of Rimini
- Kurt Grelling
- Alex Grey
- Herbert Paul Grice
- Germain Grisez
- Robert Grosseteste
- Reinhardt Grossman
- George Grote
- John Grote
- Hugo Grotius
- Adolf Grunbaum
- Guan Zhong
- Félix Guattari
- D. V. Gundappa
- Dominicus Gundissalinus
- Gotthard Guenther
- G. I. Gurdjieff
- Edmund Gurney
- Kwame Gyekye
- Susan Haack
- Juergen Habermas
- Ian Hacking
- Paul Haeberlin
- Ernst Haeckel
- Axel Anders Theodor Hagerstrom
- Yehuda Halevi
- Werner Hamacher
- Johann Georg Hamann
- Charles Hamblin
- Sir William Hamilton
- David Walter Hamlyn
- Stuart Hampshire
- Béla Hamvas
- Han Feizi
- Han Wonjin
- Han Yu
- Alastair Hannay
- Eduard Hanslick
- Norwood Russell Hanson
- John Hare
- R. M. Hare
- Gilbert Harman
- Friedrich Harms
- James Harrington
- William Torrey Harris
- H. L. A. Hart
- David Hartley
- Eduard Von Hartmann
- Nicolai Hartmann
- Charles Hartshorne
- John Haugeland
- Friedrich Hayek
- Rudolf Haym
- Hecato of Rhodes
- Friedrich Hegel
- Hegesias of Magnesia
- Martin Heidegger
- Werner Heisenberg
- Hermann von Helmholtz
- Franciscus Mercurius van Helmont
- Claude Adrien Helvétius
- Carl Gustav Hempel
- Henricus Regius
- Henry of Ghent
- Henry of Harclay
- Michel Henry
- Ronald William Hepburn
- Heraclides Ponticus
- Heraclitus of Ephesus
- Johann Friedrich Herbart
- Johann Gottfried Herder
- Herman of Carinthia
- Abraham Cohen de Herrera
- Heinrich Rudolf Hertz
- Hervaeus Natalis
- Alexander Herzen
- Abraham Joshua Heschel
- Hesiod
- Moses Hess
- Mary Hesse
- Sergei Iosifovich Hessen
- William of Heytesbury
- Hicetas
- John Hick
- Laurens Perseus Hickok
- Hierocles the Stoic
- David Hilbert
- Alice von Hildebrand
- Dietrich von Hildebrand
- Hildegard of Bingen
- Hillel ben Samuel of Verona
- Al-Hilli
- Himerius
- Hermann Friedrich Wilhelm Hinrichs
- Jaakko Hintikka
- Hipparchia
- Hippasus
- Hippias
- Hippocrates
- Ho Yen
- Thomas Hobbes
- Leonard Trelawny Hobhouse
- William Ernest Hocking
- Shadworth Hodgson
- Josef Hoëné-Wronski
- Harald Høffding
- Douglas Hofstadter
- Wesley Newcomb Hohfeld
- Baron Holbach
- Robert Holcot
- Friedrich Hoelderlin
- Oliver Wendell Holmes
- Homer
- Ted Honderich
- Sidney Hook
- Richard Hooker
- Max Horkheimer
- Jennifer Hornsby
- Paul Horwich
- Paulin J. Hountondji
- Hsi K'ang
- Hsiung Shih-li
- Hsu Fu-kuan
- Hsu Hsing
- Hu Hung
- Hu Shih
- Huai Nun Tzu
- Huang Zongxi
- Elbert Hubbard
- Pierre Daniel Huet
- Hugh of St Victor
- Hui Shih
- Wilhelm von Humboldt
- David Hume
- Edward M. Hundert
- Rosalind Hursthouse
- Jan Hus
- Edmund Husserl
- Francis Hutcheson
- Thomas Henry Huxley
- Christiaan Huygens
- Hypatia of Alexandria
- Jean Hyppolite
- Iamblichus
- Yahya ibn Adi
- Ibn al-Arabi
- Ibn ar-Rawandi
- Ibn Bajjah
- Ibn Daud
- Abraham ibn Ezra
- Moses ibn Ezra
- Ibn Falaquera
- Solomon Ibn Gabirol
- Ibn Hazm
- Hunein Ibn Ishak
- Ibn Kammuna
- Ibn Khaldun
- Ibn Masarra
- Ibn Miskawayh
- Bahya ibn Paquda
- Ibn Sab'in
- Ibn Taymiya
- Samuel Ibn Tibbon
- Ibn Tufail
- Ibn Tzaddik
- Michael Ignatieff
- Don Ihde
- Ivan Aleksandrovich Il'in
- Evald Vassilievich Ilyenkov
- Immanuel the Roman
- Roman Ingarden
- William Ralph Inge
- Muhammad Iqbal
- Luce Irigaray
- Terence Irwin
- Isocrates
- Isaac Israeli of Stella
- Issac Ben Solomon Israeli
- Isvarakrsna
- Ito Jinsai
- Frank Jackson
- Friedrich Heinrich Jacobi
- James of Viterbo
- Henry James Sr.
- William James
- Erich Jantsch
- Karl Jaspers
- Thomas Jefferson
- Richard C. Jeffrey
- Jesus Christ
- William Stanley Jevons
- Rudolf von Jhering
- Jinul
- Joachim of Fiore
- C.E.M. Joad
- John of Damascus
- John of Jandun
- John of La Rochelle
- John of Mirecourt
- John of Paris
- John of Salisbury
- John of St. Thomas
- John the Scot
- Alexander Bryan Johnson
- Samuel Johnson
- Dr. Samuel Johnson
- William Ernest Johnson
- Hans Jonas
- Jørgen Jørgensen
- Théodore Simon Jouffroy
- Juan Chi
- Judah ben Moses of Rome
- Judah Ben Samuel of Regensburg
- Carl Jung
- Ernst Juenger
- Joachim Jungius
- Justinian I
- Abul Maali al-Juwayni
- Kaibara Ekiken
- Lord Kames
- Robert Kane
- Kang Youwei
- Immanuel Kant
- Kao Tzu
- David Kaplan
- Mordecai Kaplan
- Joseph Kaspi
- Walter Kaufmann
- Karl Kautsky
- Kaydrup glek belsangbo
- Konstantin Kavelin
- Aleksey Khomyakov
- Bartholomew Keckermann
- David Kelley
- Hans Kelsen
- Norman Kemp Smith
- Anthony Kenny
- Johannes Kepler
- John Maynard Keynes
- Omar Khayyám
- Søren Kierkegaard
- Richard Kilvington
- Robert Kilwardby
- Jaegwon Kim
- Al-Kindi
- Martin Luther King
- Peter J. King
- Mark Kingwell
- Richard Kirkham
- Abu al-Hakam al-Kirmani
- Philip Kitcher
- Martha Klein
- Heinrich von Kleist
- Kleitomachos
- William Calvant Kneale
- Richard Payne Knight
- Martin Knutzen
- Ko Hung
- Arthur Koestler
- Wolfgang Koehler
- Alexandre Kojève
- Leszek Kolakowski
- Hugo Kollataj
- Alejandro Korn
- Hilary Kornblith
- Christine Korsgaard
- Tadeusz Kotarbiński
- Greg Koukl
- Alexandre Koyre
- Karl Kraus
- Karl Christian Friedrich Krause
- Georg Kreisel
- Saul Kripke
- Jiddu Krishnamurti
- Julia Kristeva
- Nachman Krochmal
- Leopold Kronecker
- Richard Kroner
- Peter Kropotkin
- Wilhelm Traugott Krug
- Erik von Kuehnelt-Leddihn
- Thomas Samuel Kuhn
- Kukai
- Kuki Shuzo
- Kumazawa Banzan
- Kuo Hsiang
- Will Kymlicka
- Louis de La Forge
- Julien Offray de La Mettrie
- Isaac La Peyrère
- Antonio Labriola
- Jacques Lacan
- Jules Lachelier
- Philippe Lacoue-Labarthe
- Pierre Laffitte
- Imre Lakatos
- Jean-Baptiste Lamarck
- Johann Heinrich Lambert
- Lamennais
- Friedrich Albert Lange
- Susanne Langer
- William Lankin
- Lao Zi
- Pierre-Simon Laplace
- Pierre Laromiguière
- Ferdinand Lassalle
- Anton LaVey
- Peter Lavrovitch Lavrov
- William Law
- Moritz Lazarus
- Jean Le Clerc
- Michèle Le Dœuff
- Antoine Le Grand
- Edouard Louis Emmanuel Julien Le Roy
- Henri Lefebvre
- Keith Lehrer
- Gottfried Leibniz
- Yeshayahu Leibowitz
- Vladimir Lenin
- Konstantin Nikolaevich Leont'ev
- Jules Lequier
- Pierre Leroux
- Stanisław Leśniewski
- Gotthold Ephraim Lessing
- Leucippus
- Emmanuel Levinas
- Claude Lévi-Strauss
- Bernard-Henri Lévy
- Lucien Lévy-Bruhl
- George Henry Lewes
- Kurt Lewin
- Clarence Irving Lewis
- C. S. Lewis
- David Kellogg Lewis
- John Lewis
- Li Ao
- Li Si
- Liang Qichao
- Liang Sou-ming
- Karol Libelt
- Georg Christoph Lichtenberg
- Lie Zi
- Alphonso Lingis
- Linji
- Carolus Linnaeus
- Israel Lipkin
- Arthur Lipsett
- Justus Lipsius
- Émile Littré
- Liu Shaoqi
- Liu Tsung-chou
- Karl Nickerson Llywelyn
- Ramon Llull
- John Locke
- Knud Ejler Løgstrup
- Alfred Loisy
- Peter Lombard
- Bernard Lonergan
- Longinus
- Cassius Dionysius Longinus
- Jakob Lorber
- Paul Lorenzen
- Aleksei Fedorovich Losev
- Nicholas Onufrievich Lossky
- Rudolf Hermann Lotze
- Arthur O. Lovejoy
- Lu Hsiang-shan
- John R. Lucas
- Lucian
- Lucius Annaeus Cornutus
- Lucretius
- Georg Lukács
- Jan Lukasiewicz
- Martin Luther
- Rosa Luxemburg
- William G. Lycan
- Jean-François Lyotard
- Gabriel Bonnet de Mably
- Ernst Mach
- Machiavelli
- Alasdair MacIntyre
- John Leslie Mackie
- John Macmurray
- Ambrosius Theodosius Macrobius
- Madhava
- Shri Madhvacharya
- Mahavira
- Salomon Maimon
- Moses Maimonides
- Maine de Biran
- Philipp Mainlaender
- John Major
- Norman Malcolm
- Nicolas Malebranche
- Mostafa Malekian
- Ernst Mally
- Merab Mamardashvili
- Bernard de Mandeville
- Karl Mannheim
- Henry Longueville Mansel
- Mao Zedong
- Gabriel Marcel
- Ruth Barcan Marcus
- Herbert Marcuse
- Juan de Mariana
- Julián Marías
- Jacques Maritain
- Gaius Marius Victorinus
- Marsilius of Inghen
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