[adapted from Questions of Value, edited by Donald Wayne Viney, 1998, Kendall/Hunt Publishing Company.]
Birth and death dates for philosophers are given in parentheses. Dates running forward are CE (or AD); dates running backward are BCE (or BC). For example, "Socrates (470-399)" means that Socrates was born 470 years before Christ and died 399 years before Christ.
Abelard, Peter (1079-1142) - French philosopher and logician notorious for his love affair with Heloise while he was preparing to become a monk. After Heloise’s uncle found the two in flagrante delicto he had Abelard castrated. A skilled, if highly controversial teacher, Abelard made enemies by being ruthless in public debate. Abelard’s Sic et Non (Yes and No) pointed to numerous contradictions among the ancient authorities of the church, but his method of debate became standard in the later middle ages. He defended an Aristotelian view of universals. Abelard and Heloise are buried together in Père Lachaise cemetary in Paris. See Heloise and universals, problem of. Books
Albert the Great (1206-1280) - Known as “the universal doctor” Albert was the teacher of Thomas Aquinas and an important interpreter of Aristotle and Plato. A number of ideas promoted by Aquinas’ can be found in Albert’s work.
Al-Farabi (died ca. 950) - Islamic philosopher who attempted to reconcile Aristotelian teaching with Islamic belief, Al-Farabi believed that the universe is an eternal emanation from God and all should strive to become one with the divine.
Al-Ghazzali (1958-1111) - Islamic philosopher who opposed the philosophies of Al-Farabi and Avicenna. The Qur’an and mystical intuition are sources of truth; the universe was created in time ex nihilo.
Al-Kindi (813-873) - Islamic philosopher of wide ranging interests including astronomy, astrology, geometry, arithmetic, music, physics, medicine, psychology, meterology, and politics. Al-Kindi translated Plotinus’ Enneads into Arabic.
Anaxagoras (499-422) - Greek philosopher who believed that a cosmic Mind (Nous) is the source of all movement of the universe’s infinitely many, and infinitely divisible, particles.
Anaximander (610-547) - Milesian philosopher who held that the unbounded (apeiron) is the source of the universe.
Anaximenes (588-524) - Milesian philosopher who held that the condensation and rarefaction of an infinite air is the source of the changes in the universe.
Aquinas, Thomas (1225-1274) - Prolific writer and Christian apologist of towering significance who combined Aristotelian philosophy and Christian faith (called Thomism). Aquinas attempted to show that reason and faith are mutually supportive while each has its own domain. Reason can support faith by showing that faith's propositions are not contrary to reason. As an empiricist he advocated the via negativa to God. He also argued that analogical language about God is possible, steering a path between the false extremes of univocal language (where terms have the same meaning when applied to God and the creatures) and equivocal language (where terms have different meanings when applied to God and the creatures). Aquinas is the premier representative of classical theism,
according to which God is wholly immutable, impassible, eternal, simple (no parts); God is pure act, with no potentiality for change. See classical theism and five ways. Books
Arendt, Hannah (1906-1975) - Student and mistress of Martin Heidegger who applied the phenomenological method to politics. She commented on "the banality of evil," the way in which people refuse to take responsibility for the evil around them.
Aristotle (384-322) - With Plato and Socrates, one of the most influential philosophers of ancient times. Aristotle’s wide ranging interests included astronomy, biology, physics, psychology, and zoology. He single-handedly developed the first formal logic which remained virtually unquestioned and was without alternative until the nineteenth century. Aristotle built his metaphysics from empirical foundations arguing that substances undergo change when their potentialities are activated by an external cause. The objects of knowledge, according to Aristotle, are universal forms extracted from particular substances by an act of abstraction of the intellect. See causes and unmoved mover. Quotes | Books
Aspasia of Miletus (ca. 470-410) - Mistress of Pericles who led a circle of intellectuals in her home in Athens; she was known as a teacher of rhetoric.
Augustine of Hippo (354-430) - Raised by a Christian mother, Monica, and a pagan father, Augustine at first rejected the faith of his mother but later was converted. He became Bishop of Hippo (in modern day Libya) and was an important interpreter and defender of Christian orthodoxy and a prolific author. Against the Pelagians, he emphasized the necessity of divine grace and the futility of human freedom in achieving salvation. His Confessions is a frank autobiographical account of his spiritual journey. Philosophically, he married Neoplatonic categories to Christian beliefs. For example, he argued that Plato’s Forms are the divine intellect. Time, he maintained, begins with the beginning of the universe itself, which God creates ex nihilo. Quotes | Books
Averroes (1126-1198) - A Spanish philosopher and physician of Arabic descent. Criticized by Christians and Muslims alike, all of whom were in his debt for his commentaries on Aristotle, Averroes like Avicenna held the doctrine that both God and the world are eternal, but the world is dependent on God.
Avicenna (980-1037) - Arabic philosopher known as “the third Aristotle,” his Latin translations of Aristotle’s works initiated a renaissance of interest in the Greeks in the 12th and 13th centuries. Avicenna lays the foundation for later thinking in Islamic and Christian circles about the relation of essence and existence in God and in the relation of God to creation. In God, essence and existence coincide and God is through and through necessary. Individuals in the universe are necessary in relation to God but contingent in themselves. God eternally creates the world; hence, the world is eternal but dependent on God. Just prior to his death Avicenna freed his slaves.
Bacon, Francis (1561-1626) - English philosopher remembered for his defense of science as a collective and state supported enterprise that should work in the service of human needs. Bacon advocated an approach to science that balanced elements of empiricism and rationalism. See Idols of the Mind. Quotes
Beauvoir, Simone de (1908-1986) - French existentialist philosopher and novelist. Beauvoir's two volume work, The Second Sex, became a sort of feminist manifesto, although she refused to identify with feminism until the last years of her life. Beauvoir writes that "One is not born a woman, but one becomes a woman" to emphasize the idea that gender is a social construct rather than a mere biological fact. Beauvoir was the life-long companion of Jean-Paul Sartre. Quotes | Books
Bergson, Henri (1859-1941) - Once popular French philosopher (said to have caused the first traffic jam in New York City when crowds rushed to hear him speak). Remarkably diverse in his interests, Bergson wrote on evolution, the nature of dreams, the origins of morality and religion, laughter, free will and the concept of time. Reality, for Bergson, is la durée (duration), a flux of events that is only imperfectly captured in the static categories of the intellect—a series of photographs of Paris, he said, is not the same as a visit to Paris.
Berkeley, George (1685-1753) - Irish empiricist philosopher, famous for the phrase Esse est percipii (to be is to be perceived). Berkeley said that the being of ideas—sensory qualities—is in their being perceived by perceiving minds or spirits. He was critical of the distinction between primary and secondary qualities. Berkeley denied the existence of a material substrate to sensory qualities and argued that the universe is sustained in existence by the mind of God. Quotes
Boethius (475-525) - Roman senator and man of letters who made contributions to logic, theology, and music theory; he composed The Consolation of Philosophy while awaiting execution in prison. The book, which was influential throughout the middle ages, presents arguments that the universe is governed by a perfect God and that even the worst suffering has its compensation. He is remembered for his definition of eternity: the whole, complete, simultaneous possession of endless life. Books
Bonaventure (1221-1274) - Franciscan theologian who argued against Aquinas that Aristotle’s doctrine of the eternity of the world is contrary to reason. Bonaventure believed that the noneternity of the world can be proved by reason.
Bruno, Giordano (1548-1600) - Anti-Aristotelian who argued for an infinite universe with other inhabited planets. Bruno was imprisoned and burned at the stake for his unorthodox philosophy.
Buber, Martin (1878-1965) - Jewishexistentialist who distinguished two fundamental ways of relating to others, to nature, and to God. In I-It relationships the other is a mere thing; in I-Thou relationships, the other is encountered as a personality.
Calkins, Mary (1863-1930) - Student of William James whose distinguished career included becoming president of the American Philosophical Association and the American Psychological Association. Calkins argued for the primacy of the self in philosophy and psychology, not as an ethical end-in-itself, but as ontologically primary.
Calvin, John (1509-1564)- Protestant reformer who held to a strong version of predestination; God causes all things to come to pass but not in such a way as to contradict human freedom.
Camus, Albert (1913-1960) - French novelist and existentialist, won the Nobel Prize for literature in 1957. In The Myth of Sisyphus he defined the absurd as the clash between the human desire for meaning and the unreasonable silence of the universe. In later works he emphasized solidarity with others in the face of life's absurdity. Quotes
Carneades (214-129) - Head of Plato's Academy who emphasized the probable over the certain.
Chrysippus (280-207) - Stoic philosopher who invented a form of propositional logic in contrast to Aristotle's class logic.
Chuang Tzu (ca. 369-286) - The last great Taoist sage. The book bearing his name was probably written by him and his followers, finding its present form by the third century BCE. Quotes | Books
Cicero (106 BCE-43 CE) - Roman scholar who affirmed the equality of men under the natural law as discernable by reason.
Confucius (551-479) - Latinized name of Kung-Fu Tzu or Master Kung, a Chinese philosopher. Confucius gives his name to Confucianism, a social, political, and ethical philosophy-religion that stresses reciprocity (shu), “Do not do to others what you would not have done to yourself.” See Confucianism. Quotes | Books
Democritus (460-370) - Greek philosopher who defended the view that the universe is composed of uncuttable bits of substance (called atoms) swirling by laws of necessity in a void. Quotes
Descartes, René (1596-1650) - French philosopher and scientist known as the “father” or “Moses” of modern philosophy. His Meditations on First Philosophy advocate that philosophical knowledge be rebuilt from the foundations, using radical doubt to clear away the falsehoods and misconceptions of former times. See Cartesian doubt, Cartesian dualism, and cogito. Quotes | Books
Dewey, John (1859-1952) - American pragmatist whose ideas profoundly influenced public education. Children are active centers of experience rather than passive receptacles for knowledge, and the educational environment should be shaped accordingly.
Diotima of Mantinea (fl. 450 BCE) - In Plato's Symposium, the priestess from whom Socrates says he learned about eros (love); and whose views on the subject Socrates expounds.
Duns Scotus, John (1265-1308) - Scottish metaphysician known as “the subtle doctor” for his careful investigations into the nature of reality and God. His De Primo Principio gives a multi-layered argument for God's existence that is the most sophistocated of the middle ages, combining elements of the ontological, cosmological, and teleological arguments. His followers were ridiculed as pedantic and called “dunces.”
Elisabeth of Bohemia (1618-1680) - Princess and pen-pal of Descartes. Elisabeth raised the embarrasing question how mind-body interaction is possible on Cartesian priniciples.
Epictetus (55-135) - Stoic philosopher and one-time slave of Nero. He stressed an ethical philosophy of detachment (apatheia) from the cares of the world and acceptance of God's inexorable will.
Epicurus (341-270) - Greek founder of Epicureanism, which says that pleasure is the ultimate good of human life (hedonism) and that long lasting and deep pleasures are the ones we should seek. In time, the concept of Epicureanism took on connotations of a philosophy of life that says, “Eat, drink, and be merry”; but this is contrary to Epicurus’ thought.
Erasmus, Desiderius (1467-1536) - Catholic humanist philosopher who defended freedom of the will against the Protestant Martin Luther.
Frege, Gottlob (1848-1925) - German philosopher and logician who replaced Aristotle’s notion of classes with the mathematical notion of a function to produce a truth-functional logic.
Freud, Sigmund (1856-1939) - Austrian psychologist and founder of psychoanalysis. Freud argued that consciousness is only a small part of the mind. The rest of the mind, called the unconscious, controls our conscious activity by means of irrational forces. Hence, Freud was highly skeptical of traditional concepts of free will. Quotes
Gandhi, Mohandas (1869-1948) - Indian political leader and philosopher who advocated ahimsa (non-injury) as a method of political change.
Gorgias (483-380) - Greek sophist who poked fun at the pretentions of philosophers by arguing that nothing exists, if something exists then it cannot be known to exist, and if it can be known to exist then it cannot be communicated. Quotes
Hartshorne, Charles (b. 1897) - American philosopher and theologian who has also written on ornithology. For Hartshorne, metaphysics is the search for necessary existential truths. The key to metaphysics is the asymmetrial relations between ultimate contrasts. Thus, effects include causes but not vice versa—hence, indeterminism is true; or again, the relative includes the absolute but not vice versa—hence, God, as the all-inclusive being, is internally related to all that is. Hartshorne argues for God's existence using a "global argument" incorporating versions of the ontological, cosmological, design, epistemic, moral, and aesthetic arguments. See most and best moved mover. Quotes
Hegel, G. W. F. (1770-1831) - German philosopher. In Phenomenology of Spirit Hegel provides a history of consciousness. Humans seek self-knowledge, but discover that the "truth" of the self is only found in recognition from others. We seek to liberate ourselves through domination of nature and of others. Only universal human rights resolves the "contradiction." History itself is the process of the Absolute spirit coming to awareness of itself in time and human culture. Quotes | Books
Heidegger, Martin (1889-1976) - German philosopher, student of Husserl, whose Being and Time (1927) became a foundational work for twentieth century existentialism. Identifying Dasein as being-in-the-world, Heidegger finds no transempirical self rising above time. Human existence, which is an instance of dasein, is a being-towards-death whose very authenticity depends upon full recognition of this fact. Heidegger's later work stressed the importance of language for being-in- the-world. Language is "the house of being." Books
Héloïse (1101-1164) - Mistress of Peter Abelard, with whom she bore a son. Héloïse's letters to Abelard after their affair are literary and philosophic classics. She became abbess of a convent called the Paraclete. See Abelard.
Heraclitus (540-475) - Greek philosopher who said, “You cannot step into the same river twice,” thus emphasizing the primacy of change, movement, and time. He added, however, that all change is governed by a rational principle called the logos. Quotes
Hildegard of Bingen (1098-1179) - German mystic, medical writer, and composer.
Hobbes, Thomas (1588-1679) - English philosopher and author of Leviathan who developed a thoroughgoing materialistic account of experience; even God is made of matter. In political philosophy, Hobbes argues that the goal of reason is long-term preservation. Citizens in a stable society ought to give up their rights (except the right of self-defense) to a sovereign to decide what is best for the long term. Quotes | Books
Hsun Tzu (3rd century BCE) - Confucian philosopher who emphasized the essential waywardness of human beings.
Hume, David (1711-1776) - Scottish empiricist philosopher who traced all knowledge to sense impressions and the ideas derived from them. Hume's empiricism does not support belief in an enduring self or necessary connections between causes and effects. Hume's skepticism of miracles, the afterlife, and traditional arguments for the existence of God continues to be influential. Quotes | Books
Husserl, Edmund (1859-1938) - German founder of phenomenology. For Husserl, phenomenology is the science whose job it is to uncover essences through the method of eidetic variation. Traditional philosophical questions about the nature of the self, the world, and God are bracketed or set aside in order to examine experience, the only thing-in-itself. Science begins with sensory experience; but the foundation of phenomenology is imagination. See intentionality. Quotes | Books
Hypatia of Alexandria (c. 370-415) - Neoplatonist philosopher-mathematician who, as head of the Library in Alexandria, Egypt, lectured on Plato and Aristotle. Hypatia was murdered by a mob of thugs loyal to St. Cyril, the Christian Bishop of Alexandria.
James, William (1842-1910) - Brother of the novelist Henry James and founder of American psychology and promoter of pragmatism, radical empiricism, and pluralism. James rebeled against all-emcompasing systems that impose unity on the universe and explain away the disunities. His defenses of chance, indeterminism, free will, and a limited God are aspects of this pluralism. Quotes | Books
Jesus of Nazareth (ca. 4 BCE - 30 CE) - A Jewish itinerate teacher, considered by Christians to be the Messiah, the Christ—hence, followers of Jesus are called Christians. He left behind no writings, but according to those who wrote about him, he advocated an ethic of unqualified love of God and of others. The New Testament of the Bible reports that three days after he was killed by crucifixion he rose from the dead (here the New Testament and the Muslim Qur'an contradict one another). See agape.
Kant, Immanuel (1724-1804) - German philosopher who, in metaphysics and epistemology, tried to steer a course between empiricism and rationalism. Rather than the mind conforming itself to the conditions of experience, experience is possible only because its objects must conform to the structure of the mind. This makes synthetic a priori judgments possible. However, things-in-themselves (the noumena) are unknowable; we know only things as they appear to the mind (the phenomena). In ethics, Kant advocated the categorical imperative as the basis of all ethical judgment. In one of its forms the categorical imperative says, "Act so as to treat others, yourself included, always as an end-in-itself, and never as a means to an end only."
Quotes | Books
Kierkegaard, Søren (1813-1855) - Danish Chrisitian existentialist philosopher. Using Hegel's philosophy as a foil, Kierkegaard distinguished objective truth and subjective truth, the later having to do with the degree of passion with which one holds a belief. Subjective truth, and the individual who possesses it, can never be captured in the objective truths of philosophy and science. Subjective truth is what matters most in religion. Quotes | Books
King, Martin Luther (Jr.) (1929-1968) - Christian civil rights leader who advocated nonviolent passive resistance as a method of changing unjust laws.
Langer, Suzanne (1895-1985) - American student of A. N. Whitehead known for her work in aesthetics based on a distinction between signs (which are tied to specific stimuli, as in a warning call) and symbols (not tied to specific stimuli), which are central to human awareness.
Lao Tzu - Li Tan by birth; a contemporary of Confucius, born ca. 604 BCE; legendary author of the Tao Te Ching (although scholars acknowledge that Lao Tzu, even if he existed—some debate his existence—could not have written the entire book). Quotes | Books
Leibniz, Gottfried (1646-1716) - Prussian philosopher, logician, and co-inventor of the calculus (Isaac Newton invented the calculus before Leibniz but Leibniz was the first to publish his work). According to Leibniz the universe is composed of immaterial and indestructible monads with the inner characteristics of perception and appetition. The monads do not interact with each other but only appear to interact due to the pre-established harmony imposed by God. Leibniz's Theodicy is parodied in Voltaire's Candide. Books
Lequyer, Jules (1814-1862) - French Breton philosopher who influenced Charles Renouvier and William James on the subject of free will. A person is a "dependent-independence" in the sense that much of life is deterministic but there are arenas in which free will operates. Deeply religious, Lequyer proclaimed his faith in "God, who created me creator of myself." Quotes
Locke, John (1632-1704) - English empiricist philosopher. There are no innate ideas; all ideas in the mind come from the senses, the only world we know is the world as it presents itself to us in representations before the mind. Hence, substance, not being given in the senses, is “something I know not what” that underlies what one perceives as an object. In Locke's influential political philosophy, he argued that the rights to life, liberty and property are God-given to all men. Quotes
Madhva (1197-1276) - Vedantan philosopher who upheld the position of extremem dualism--Brahman and Atman are ontologically distinct but the individual may become one with Brahman in ethical purpose.
Mahavira (599-527) - Indian sage and founder of Jainism whose name means “Great Hero.” Mahavira wore no clothes and, in accord with the doctrine of ahisma, died of ritual starvation. See ahisma, Jainsim, karma.
Maimonides, Moses (1135-1204) - Jewish Spanish philosopher who relied heavily on the via negativa (we know what God is not) and Aristotelian theistic arguments to argue that there is no final conflict between faith and reason. Books
Mani (216-277) - Self-proclaimed saoshyant, or savior, founder of Manicheism; a heresy for orthodox Zoroastrians because of its doctrine of the evilness of the world.
Marcel, Gabriel (1189-1973) - French existentialist and convert to Catholicism who argued that life is less a problem to be solved than a mystery to be lived.
Marx, Karl (1818-1883) - German philosopher and economist who argued against capitalism and for communism. Capitalism is dehumanizing since it entails an alienation of the worker from the products of his or her labor. The capitalist uses “surplus value” to expand business and keep worker's wages low. By this process, the rich get richer and the poor get poorer; the economic gap between bourgeois and proletariat grows ever wider. Marx believed that this process is self-destructive and would eventually lead to a communist form of government in which private property would be abolished. Marx's Communist Manifesto (1847), co-authored with Fredrich Engels, is a call to workers to unite against those who control the means of production of material life. Marx's well-known atheism involves an analysis of the conditions under which people resort to religioius beliefs.
According to Marx, religion is an opiate, that is to say, a drug, that people take to escape the intolerable conditions of material life. In a communist society, religion would no longer be necessary. Quotes | Books
McTaggart, John E. (1866-1925) - British Hegelian best remembered for his advocacy of the unreality of time. There are two ways of marking positions in time which McTaggart calls an A-series (past, present, future) and a B-series (earlier, later). Time, considered as a movement or change, exists only if the A-series is real. But the A-series entails that any particular event has the contradictory properties of being past, present, and future.
Mencius (372-289) - Latinized form of Meng-tzu; Confucian philosopher known for emphasizing the essential goodness of human beings.
Mill, John Stuart (1806-1873) - English ethicist, political philosopher, and logician. Mill advocated utilitarianism in ethics and in his political thought emphasized the role of government in protecting liberty. He has the happy distinction of being one of the few male philosophers who advocated for women's rights. Mill's wife, Harriet Taylor (1808-1858), also wrote on this subject. Mill's contributions to logic are in a careful analysis of the forms of inductive reasoning. Quotes | Books
Montaigne, Michel de (1533-1592) - French philosopher who stressed human fallibility. Carved into the beams of his study was the motto, “Que sais je?” (What do I know?). He argued that skepticism about our ability to know is most consistent with the Christian religion and leads to greater tolerance of people with whom one disagrees. Montaigne is also known as the inventor of the essay form of writing. Quotes | Books
Muhammad (570-632) - Born Ubu'l Kassim, the main prophet of Islam, believed by Muslims to be the last and greatest of Allah's prophets. See Islam.
Mo Tzu (479-381) - Rival of Confucian thought who taught universal love and mutual benevolence.
Nietzsche, Friedrich (1844-1900) - German iconoclast philosopher who advocated a philosophy of will-to-power. Nietzsche proclaimed the death of God, and with it, the nonexistence of objective values. Humans create their own world. The only permanence is the eternal recurrence of all that has ever been in exactly the order and sequence in which it occurred; although Nietzsche rejected determinism, the doctrine of the eternal recurrence insures that there is no genuine novelty. The ideal man, the Overman, is the one who loves his fate and rejoices in his will-to-power. Although Nietzsche associated with women of great intellectual power, he held a less than flattering view of their abilities. See Salomé, Lou. Quotes | Books
Parmenides (515-450) - Greek philosopher and defender of extreme monism. All time, plurality, and change are unreal.
Pascal, Blaise (1623-1662) - French philosopher, mathematician, and inventor. Pascal contributed to probability theory and thought of the idea of the bus. Pascal experienced a dramatic conversion to Christianity in 1654, expressed in his “memorial,” a brief written statement of the experience, which he sewed into the hem of his jacket. In the “memorial” he distinguishes the God of the philosophers and the God of Abraham, Isaac, and Jacob and of Jesus Christ. He died before completing his Pensées (Thoughts), a Christian apologetic work. For Pascal, human existence is caught between the infinitely great and the infinitely small; the human dilemma is to be unable to prove what one believes and to be unwilling to succumb to extreme skepticism. The way out of this dilemma is through faith. See fideism and
Pascal's wager. Quotes | Books
Paul (died ca. 64 CE) - A convert from Judaism to Christianity who, in the years following Jesus' death, was a moving force behind Christianity. His writings comprise about a third of the New Testament. His ministry was mainly to non-Jews (i.e. Gentiles).
Peirce, Charles Sanders (1839-1914) - American philosopher and logician, and founder of pragmatism. Peirce's metaphysics is based on three categories: Firstness, or quality and independence; Secondness, or reaction and dependence; and Thirdness, or generality and relation. Using these categories Peirce argued for the reality of time, chance, and laws of nature (as against the nominalists). Peirce maintained contrary to Darwin that evolution, which involves increasing complexity, requires indeterminism, rather than determinism. With Frege, Peirce is the co-founder of modern propositional logic. Quotes | Books
Plato (427-347) - Student of Socrates, teacher of Aristotle, and founder of the first university, the Academy (because it was in the grove of Academus). Plato emphasized education since he believed that knowing the true, the good, the beautiful, leads to doing the good and creating the beautiful. The objects of knowledge are the unchanging and eternal Ideas or Forms. The senses distract us from this knowledge. The soul's intellectual power, in concert with its spiritedness, must discipline the wayward senses to achieve true virtue. Learning is a type of remembering what we have forgotten--the reality of Forms. For Plato, the soul is immortal and undergoes successive incarnations until it finally achieves release from the physical world.
Plato also held that the soul alone is self-moving (as opposed to receiving all movement from another); the world-soul, according to one interpretation, shaped the universe by weaving the self-movement of finite souls into the skein of Forms. Quotes | Books
Plotinus (205-270) - Neoplatonic philosopher who argued that the universe comes into existence by successive emanations from the divine.
Popper, Karl (1902-1994) - Austrian-British philosopher of science most noted for his anti-positivist criterion of falsifiability. A scientific theory is good, not to the extent that evidence verifies it, but to the extent that it can be shown to be false, but withstands the challenges to it. Popper also opposed determinism and he is a strong advocate of the “open society” as against closed totalitarian states.
Pythagoras (570-490) - Greek philosopher and founder of the Pythagorean school which heavily influence Plato. The Pythagorean theorem is associated with Pythagoras, but he also laid the foundations of music theory. Pythagoreans believed in reincarnation, vegetarianism, and the importance of numbers in understanding the cosmos.
Quine, Willard Van Orman (b. 1908) - American philosopher and logician who argues that philosophy has no province apart from science. His essay “Two Dogmas of Empiricism” attacks the interrelated ideas that there is a strict dichotomy between analytic and synthetic truths and that scientific statements can be reduce to statements about sensory input. Quine views scientific knowledge less as an edifice built on sensory input than as a web of beliefs, no strand of which is immune to revision. Quotes
Ramanuja (1017-1137) - Vedantan philosopher who upheld the position of qualified nondualism--the universe is Brahman's body and individual souls are parts of Brahman, though distinct from it.
Rand, Ayn (1905-1982) - Russian novelist and philosopher who became popular for defending ethical egoism: one's sole duty is to oneself. Rand criticized traditional ethics for being excessively other-directed thereby devaluing self.
Renouvier, Charles (1815-1903) - Tireless and prolific French personalist whom William James called “the great Renouvier.” Like James, Renouvier was a pluralist and indeterminist who believed in the reality of free will and chance in nature. He spoke of uchronie, the idea that small alterations in history could have vast and important effects. To his dying days (he dictated a book on his deathbed) he referred to Jules Lequyer as his “master” in philosophy.
Rorty, Richard (b. 1931) - As a postmodernist Rorty questions the metaphysical pretensions of modern philosophy, adopts cultural relativism and nominalism. Argument, Rorty claims, is not a method of finding truth but an exercise in rhetoric, redescription, and persuasion. He advocates an attitude of irony since no system of beliefs--including beliefs in the dignity of human beings and the abhorrence of tyranny which Rorty holds--can claim to be true. See postmodernism, relativism, nominalism.
Rousseau, Jean-Jacques (1712-1778) - Swiss-French political theorist who believed unjust social conditions corrupt a basically good human nature. Ideal government is found in the general will for the common good which, given liberty, eventually arises as human excesses cancel each other out. Quotes
Royce, Josiah (1855-1916) - American Idealist who held that reality is the actual content of an immutable Absolute. In ethics, Royce argued that interest in others is more basic than self-love, making community possible.
Russell, Bertrand (1872-1970) - English philosopher, logician, and political activist. Russell was initially attracted to Idealism, but he abandoned it in favor of a philosophy that stresses mathematics, logic, and sense experience. Russell developed a theory of descriptions according to which names are disguised descriptions. This solves the puzzle of how nonreferring expressions are possible, as in Russell's example: The present king of France is dead. According to Russell's theory, the sentence means “There is one and only one person who is the present king of France and that person is dead.” Since the first part of the sentence is false--there is no present king of France--the sentence is false. Russell is also famous for his distinction between knowledge by acquaintance and knowledge by description. To know by acquaintance is to have personal knowledge, as when one knows a person.
To know by description is to know truths about a thing, as when one knows that person is honest. Russell was an atheist who argued that, on balance, religion does more harm than good. See Russell's paradox. Quotes | Books (with A. N. Whitehead)
Salomé, Lou Andreus (1861-1937) - Friend of Nietzsche and author of the first book on his thought entitled Nietzsche in seinen Werken (1894).
Sankara (788-820) - Vedantan philosopher who upheld the position of unqualified nondualism--Atman is indistinguishable from Brahman, for Brahman is wholly without duality.
Sartre, Jean-Paul (1905-1980) - French existentialist philosopher whose classic, Being and Nothingness, develops a dualistic ontology between en-soi (in-itself; things) and pour-soi (for-itself; consciousness). The self is a creation of consciousness and hence transcends consciousness and classifies as en-soi, although in bad faith consciousness continually treats itself as a mere thing. The result is that we are “condemned to be free.” Sartre says that “existence precedes essence,” meaning that there is no essence predetermined by God or nature that decides our existence--indeed, Sartre was an atheist. Quotes | Books
Socrates (470-399) - Teacher of Plato and often considered the father of the dialectical method in philosophy--a question and answer method of finding truth. Socrates wrote nothing and spent his later years urging the people of Athens to seek wisdom above all else. He was accused of impiety and of corrupting the youth, found guilty, and put to death by drinking hemlock. His defense at his trial, as recorded by Plate in The Apology, humorously turns the tables on his accusers by making them the defendants against the charge of injustice. According to Socrates, “The unexamined life is not worth living.” Quotes
Spinoza, Baruch (1632-1677) - Jewish philosopher of Portuguese descent who resided in the Netherlands and made his living as a lens grinder. Spinoza questioned the Mosaic authorship of the Torah and was skeptical that the miracles in the Bible occured as described. He was excommunicated from the synagogue. Nevertheless, he argued for an “intellectual love of God,” which God he identified as the entire universe. Spinoza contributed to modern psychology and medicine by denying supernatural causes of afflictions and advocating the search for naturalistic explanations of illness and disease. Quotes | Books
Teilhard de Chardin, Pierre (1881-1955) - French priest and paleontologist who worked to reconcile Catholicism with belief in evolution. Teilhard found direction in evolutionary processes towards ever increasing physical complexity and a corresponding augmentation of consciousness. Projecting this process into the future, Teilhard foresaw a noosphere, a collective global consciousness that eventually converges at the “Omega Point,” the Christosphere, which is creation consummated in the being of God. Quotes
Thales (640-546) - Milesian philosopher who believed water is the source of all existence and that “everything is full of gods.”
Voltaire (1694-1778) - Philosopher, man of letters and science, and humorist. Voltaire's ideas paved the way for the French Revolution, although he would have disapproved of the direction it tool. Taking as his motto, “Écrasez l'infâme” (Wipe out infamy), Voltaire defended freedom of thought and conscience against the political and religious tyranny of his day. An early deist, he used a version of the design argument to support his belief in God. Quotes
Weil, Simone (1909-1943) - French philosopher-mystic who contrasted the weight of worldly concerns (gravity) with the love of God (grace). Weil actively identified with those less fortunate by volunteering for manual labor and participating in the laborer's daily life, a life to which her frail constitution was not suited. Quotes
Whitehead, Alfred North (1861-1947) - English philosopher who spent the last twenty-three years of his life at Harvard. He was co-author with Bertrand Russell of Principia Mathematica (1910-13) but later shifted emphasis to metaphysics. His magnum opus, entitled Process and Reality (1929), inspired the movements known as process philosophy and theology. Whitehead offered as a working hypothesis that reality, from the smallest bits of matter to God, is composed of processive centers of experiential activity entering into dynamic relations with each other. Quotes | Books (with Bertrand Russell) | Books
Wittgenstein, Ludwig (1889-1951) - Austrian philosopher, educated in England, whose Tractatus Logico-Philosophicus (1921) influenced the logicial positivists by its stress on the importance of logic as providing the limits within which meaningful statements can be made. Wittgentstein was not, however, a logical positivist, and his later philosophy, particularly in Philosophical Investigations (1953), emphasized the varieties of uses to which language is put. Quotes | Books
Wollstonecraft, Mary (1759-1797) - English political philosopher who argued for equal rights for women. Equality between the sexes is impossible unless there is equal access to education.
Xenophanes (570-500) - Greek skeptical philosopher who criticized anthropomorphism in religion. Xenophanes argued that if lions and giraffes had religions, their gods would be lion-like and giraffe-like. Quotes
Yang Chu (ca. 4th century BCE) - Considered the forerunner of Taoism. Stressed the hedonistic, reclusive life. His philosophy could be described as egoistic utilitarianism.
