rtha Gautama is commonly known as the Buddha which means “the enlightened one.” Born in India, his teachings became the foundations of Buddhism, one of the world’s major religions.Here are brief sketches, listed chronologically, of some of the thinkers mentioned in this book. These thinkers are the inspiration for many of the ideas in the foregoing chapters, as well as in our civilization. You should also look at the References beginning on page 221 below.
Buddha (around 563–483 B.C.E.)
Siddhrtha Gautama is commonly known as the Buddha which means “the enlightened one.” Born in India, his teachings became the foundations of Buddhism, one of the world’s major religions.
The core of these teachings is the Four Noble Truths: the existence of suffering, the cause of suffering, the possibility of restoring well-being, and the Noble Eightfold Path for the ending of suffering and the attainment of Enlightenment.
Unlike Abrahamic religions, Buddhism is primarily concerned with the individual’s enlightenment. The Buddha did not endorse belief in any gods or other supernatural phenomena.
Plato (427–347 B.C.E.)
Plato is the most influential and best known philosopher of the Western tradition. According to the outstanding twentieth-century philosopher Afred North Whitehead, “the safest general characterization of the European philosophical tradition is that it consists of a series of footnotes to Plato.”
Plato wrote dialogues—discussions between his teacher Socrates and various other Greeks with a range of different opinions. These dialogues present Plato’s views on the nature of reality, knowledge, art, ethics, and the state. The most famous of these are the Republic (about the ideal form of government) and the Apology (about Socrates’s trial for impiety).
Plato is what philosophers call an idealist—he argues that reality consists in abstract ideas or forms and that the world we perceive and live in is but a reflection of this true reality. This conception is memorably presented in Plato’s celebrated Allegory of the Cave.
Aristotle (384–322 B.C.E.)
A student of Plato, Aristotle is sometimes referred to simply as “The Philosopher.” He was the first to formalize reasoning into the discipline of logic. More empirically minded than Plato, Aristotle rejected Plato’s idealism, arguing instead that true reality is in the concrete, particulars, not abstract ideas.
Aristotle wrote treatises spanning many areas of knowledge, including biology, art, psychology, ethics, politics, physics, and mathematics. His ideas dominated medieval European thinking and are still influential today.
St. Thomas Aquinas (1225–1274)
Aquinas is the most famous and influential of the Scholastic philosophers. Aquinas drew directly upon Aristotle, and upon the Muslim writer Averroes (ibn Rushd) and the Jewish writer Maimonides (Moshe ben Maimon), both of whom worked to integrate Aristotle into their respective religious traditions.
Aquinas’s ideas (known as ‘Thomism’) were not recognized by the Church when he was alive, and were sometimes condemned. His insistence on logic—for example that God could not perform the logically contradictory, and that the existence of God could be proved by reason alone—was felt to be dangerous. But Aquinas was made a saint fifty years after his death and later became completely respectable, and then the single officially approved philosophy of the Church.
Among Aquinas’s achievements were his Five Ways (of proving the existence of God), his analysis of just and unjust wars, and his development of ‘natural law’ as the basis for human community life, law, and ethics. Politically, he favored monarchy, defended slavery, and endorsed the use of violence against heretics. His most important writings are Summa Theologica, Summa contra Gentiles, and his commentaries on Aristotle.
Much philosophical thinking after the fifteenth century is a critical reaction against the Scholasticism embodied in the writings of Aquinas.
Thomas Hobbes (1588–1679)
Although writing in the seventeenth century, English philosopher Thomas Hobbes’s thought is decidedly modern in many ways. He is best known for his political philosophy expounded in Leviathan (though he also developed a materialist theory of the physical world).
Hobbes’s political philosophy is focused on creating and maintaining social and political order. In order to avoid the chaos and insecurity of what he called the state of nature, Hobbes argued that we ought to submit to the power of an absolute sovereign who will make all political decisions.
Although few today accept Hobbes’s conclusions, his arguments are still widely influential in contemporary political philosophy.
René Descartes (1596–1650)
The seventeenth-century French philosopher René Descartes challenged Scholasticism, the dominant philosophy of medieval Europe, and introduced methods and concepts that still frame contemporary philosophy.
Descartes is best known for his argument for certainty based on The Cogito. The Cogito, “Cogito ergo sum,” is the proposition that translates as “I think, therefore I am.” Descartes decided, as an exercise, to try to doubt everything he believed. He argued that there was just one thing he could not doubt: his own existence, since he was continually aware of his thoughts. From this, by an extended process of reasoning, he derived the existence of the physical world and of God.
Descartes is also known for mind-body dualism: the theory that the mental and the physical are entirely distinct and dissimilar substances. So, subjective mental events such as thoughts and feelings are not physical and belong to the soul.
His most important works are his Discourse on the Method and Meditations.
John Locke (1632–1704)
John Locke’s life was bound up with the revolutions in England in the seventeenth century and his writings helped form the thinking of the American revolutionaries. Locke is generally regarded as the key figure in the foundation of classical liberalism: private property, limited government, and the free market. He argued against the theory of absolute monarchy and in favor of religious toleration. His influence can easily be seen in such documents as the US Declaration of Independence. Thomas Jefferson considered Locke one of the three greatest men of all time (the other two being Francis Bacon and Isaac Newton).
In his Second Treatise of Government (1689), Locke maintained that the true function of government is to protect individuals’ rights, notably their property rights.
His greatest work, An Essay concerning Human Understanding, argues for the philosophical theory known as empiricism: that knowledge is based on the evidence of our senses.
David Hume was a Scottish philosopher renowned for his work in epistemology and ethics. His Treatise of Human Nature (1740) is generally acknowledged to be the most brilliant work of pure philosophy ever written in English.
Skeptical of our ability to know anything for certain, Hume challenged the standard accounts of perception, knowledge, causality, and ethics. He questioned the assumption that ethics could be derived from factual descriptions of the world; no set of affairs in the world can by itself entail any particular moral judgment—this is the famous problem of ‘ought’ and ‘is’. Instead, he maintained that we are motivated to act by our emotional responses, in particular, sympathy.
Like his English predecessor Locke, Hume was a classical liberal whose ideas on morality, law, government, and economic life influenced the American Founders.
Adam Smith (1723–1790)
Although best known as the father of economics, Adam Smith was first and foremost a moral philosopher. In his Theory of Moral Sentiments, Smith defended a view of human virtue grounded in sympathy and pleasure. He argued that it is through seeing, even experiencing, the painful or pleasurable effects of our actions on others that we develop the virtues necessary both for living well with others and for leading a happy life of our own.
In An Inquiry into the Nature and Causes of the Wealth of Nations, Smith founded ‘political economy’ (now called economics) by bringing together and developing everything that was then known about the theory of economic life. Smith outlined the social and political requirements necessary for a free and prosperous society, and argued for free trade.
Together, these two great works of Smith present a systematic understanding of human nature and peaceful social interaction.
Immanuel Kant was a German philosopher who revolutionized modern philosophy. His work in metaphysics and epistemology made previous philosophical points of view seemingly irrelevant. Rather than seeing our knowledge and minds as passively conforming to external reality, Kant argued that our minds must play an active role in creating our picture of reality. He advanced the highly controversial view that such basic categories as space, time, and causation are not derived from experience, but are inherent in the mind, so that we are unable to think outside of them.
Kant’s ethics has also been influential. His ethics is called ‘deontological’, meaning that it is not based on evaluating the consequences of actions, but rather on whether actions conform to basic moral rules and whether a person adopts those rules with a good will. He formulated the Categorical Imperative that prescribes the only appropriate reason for acting: “Act only according to that maxim by which you can at the same time will that it should become a universal law.”
Politically, Kant was a liberal who argued for the freedom of the autonomous individual to decide upon his own beliefs and actions without being subject to any authority.
Jeremy Bentham (1748–1832)
Jeremy Bentham was an English philosopher and reformer best known for his formulation of the principle of the utility: the greatest happiness for the greatest number. One of the founders of Utilitarianism, Bentham argued that the test of right or wrong was whether an action or policy produced greater happiness for more people than the alternative.
As a radical reformer in eighteenth- and nineteenth-century England, Bentham advocated social policies such as freedom of expression, equal rights for women, and economic freedom because he claimed they would produce the greatest happiness for the greatest number.
Georg Wilhelm Friedrich Hegel (1770–1831)
Notoriously hard to understand, Georg W.F. Hegel was a German philosopher who developed a comprehensive philosophical system that explained civilization in terms of the historical developments of ideas. His absolute idealism attempted to make sense of reality as a whole that included both subject and object. He also developed a kind of dialectical reasoning that sought to make sense of oppositional ideas as new unified concepts. His views influenced Karl Marx and generations of Continental philosophers.
Ralph Waldo Emerson (1803–1882)
A uniquely American thinker, Ralph Waldo Emerson was a popular and influential essayist and lecturer in the nineteenth century. The leader of the Transcendentalist Movement, he spoke out against slavery and criticized popular religion. His essays put forward an optimistic and romantic vision of the individual. His essay “Self-Reliance” is still widely read and anthologized.
John Stuart Mill (1806–1873)
Like his mentor and contemporary Jeremy Bentham, John Stuart Mill was an English philosopher and reformer. He articulated his version of ethical philosophy in his famous work Utilitarianism. Unlike Bentham who treated all pleasures as equal, Mill distinguishes between different kinds of pleasure. This meant that some pleasures could count more when subjecting one’s actions to the principle of utility.
In his On Liberty Mill presented a robust defense of individual freedom and his The Subjection of Women provided one of the first calls for full legal and moral equality of women.
Søren Kierkegaard (1813–1855)
One of the fathers of Existentialism, the Danish philosopher Søren Kierkegaard wrote largely on questions of religion and human freedom. Kierkegaard focused on the individual and the choices and commitments the individual made, in particular regarding one’s faith. He explored the nature of emotions, such as despair, angst, and love.
Kierkegaard is also well-known for his three stages of individual development: the aesthetic, the ethical, and the religious.
Karl Marx (1818–1883)
Best known as the co-author, with Friedrich Engels, of the Communist Manifesto (1848), Karl Marx developed an influential theory of political economy that called for radical changes to the structure of economic and political life. According to Marx, different classes in society have different and conflicting interests. He argued that history is best understood as a history of these class conflicts.
Although trained as a philosopher, Marx’s great four-volume work, Capital, is a work of economic theory, in which he criticizes apologists for capitalism and looks forward to its replacement by communism. Marx tried to show that the workers create all economic value, and that the employer’s or investor’s profit is due to a part of the workers’ labor that is not recompensed. Because of capitalism’s inherent instability, increasing monopolization, and the growing power of the workers, Marx expected that capitalism would be abolished and replaced by communism, a system in which there would be no private property and in which the state would gradually cease to exist.
Marx is well-known for the theory called ‘historical materialism’: that changes in technology give rise to changes in the economy, which then gives rise to changes in the whole culture.
Marx’s ideas have had little impact on economics or philosophy, but considerable impact on history and sociology.
William James (1842–1910)
William James was an influential professor of psychology and philosophy at Harvard University.
A central figure in American Pragmatism, James articulated a radical view of knowledge and truth. An idea was true, he argued, if we could both incorporate it into our current manner of thinking and show its usefulness in our lives.
He is also well known for his examination and explanation of religious experience in The Varieties of Religious Experience.
Friedrich Nietzsche (1844–1900)
Friedrich Nietzsche was a German philosopher whose writings challenged, and continue to challenge, the philosophic mainstream. He famously declared that “God is dead” and criticized religion, Christianity in particular, at its core. His ethics can either be read as a kind of nihilism or as a radical call for self-realization and self-affirmation. Considered by some to be one of the fathers of Existentialism, Nietzsche’s writings were more literary than those of other philosophers.
Nietzsche was deeply concerned with authenticity and meaning in one’s life and less concerned about a consistent and systemic approach to knowledge.
His most famous works are Thus Spoke Zarathustra, The Gay Science, and Beyond Good and Evil.
Maria Montessori (1870–1952)
One of the most influential thinkers on education, the Italian-born physician and educator developed a systematic method and curriculum based on her close observations and study of children learning. She argued that children naturally learn in reaction to their environment. The role of the educator is thus first to remove obstacles to this process and second to fashion the child’s environment to facilitate his or her development.
Her method is still widely used in many schools throughout the world.
Joseph Schumpeter declared that his ambitions had been to become the greatest economist in the world, the greatest horseman in Austria, and the greatest lover in Vienna––and that he had fulfilled two of these three (he did not specify which).
Schumpeter is best known to the general public for his book Capitalism, Socialism, and Democracy and to economists for his two-volume Business Cycles. He argued that capitalism would be so successful it would lead to the creation of an intellectual class that would seek capitalism’s destruction, and a culture which would be unfavorable to entrepreneurship, capitalism’s driving force.
Though he was pessimistic about the future of capitalism because of his dim view of the intellectuals, Schumpeter argued that through constant innovation and entrepreneurship, capitalism, if it were allowed to, could continue to flourish and improve everyone’s lives indefinitely.
Schumpeter famously invented the term “creative destruction” to characterize the ceaseless process of innovation and entrepreneurship which drives progress.
Martin Heidegger (1889–1976)
One of the most controversial and influential philosophers of the twentieth century, Martin Heidegger is a key figure in the philosophical movements known as phenomenology and existentialism.
Heidegger’s most famous work, Being and Time, is an attempt to explain human beings in terms of their fundamental existence in time. He was also concerned with what would make one’s life truly authentic. His philosophy is often challenging and frequently confounding, but Heidegger’s notorious support of Nazism remains his most disturbing legacy.
Jean-Paul Sartre (1905–1980)
Jean-Paul Sartre was a leading French existentialist and phenomenologist, whose work primarily focused on the individual’s radical freedom of action and the correlative responsibility that comes with that freedom.
Sartre maintained that freedom is inescapable—we are “condemned to be free,” but most people deceive themselves in an attempt to evade this freedom and responsibility, so that they end up living inauthentic lives. His most important philosophical work, Being and Nothingness, is an attempt to explain human beings in terms of the relationship between consciousness and reality.
Sartre was also an outstanding novelist and playwright. His greatest works are Nausea, The Age of Reason, and No Exit.
Ayn Rand (1905–1982)
The Russian-born novelist-philosopher was the author of two of the best-selling books of all time, the novels The Fountainhead and Atlas Shrugged. Her fiction and non-fiction writings present her philosophical views which are broadly based in the Aristotelian tradition.
Atlas Shrugged describes what happens when the small number of creative geniuses—entrepreneurs, engineers, scientists, and artists—decide to withdraw from society, in effect going on strike.
Rand argued for realism and reason in metaphysics and epistemology, moral individualism in ethics, and libertarianism in political philosophy.
Philippa Foot (1920–2010)
Philippa Foot was a British philosopher best known for her work in ethics. She helped to revive interest in Aristotle’s ethics as part of contemporary Virtue Ethics. In Natural Goodness, her last published work, she sets out a defense of morality that is grounded on human nature and practical reason. Her influence in contemporary ethics is largely based on her enduring critiques of dominant ethical viewpoints, namely non-cognitivism and consequentialism.
The English-born economist is an emeritus professor of economics at New York University. He is best known for his work on entrepreneurship.
The entrepreneur in Kirzner’s view plays an essential role in markets by discovering and developing untapped opportunities. Kirzner is critical of dominant viewpoints in more mainstream economics that often rely on static mathematical models and ignore the indispensable role of the entrepreneur.
John R. Searle (1932)
The American philosopher, John Searle, teaches at UC Berkeley and is best known for his contributions to philosophy of language and philosophy of mind. He made his reputation with his theory of speech acts; speech acts are utterances (such as saying “I do” at the appropriate time in a wedding ceremony) that are actions doing something in the world (making you married).
His Chinese Room thought experiment, first published in the early 1980s, spawned a cottage industry in philosophy, with thousands of publications attacking and defending it. The thought experiment is intended to counter various claims made about artificial intelligence. So-called “Strong AI” holds that, with sophisticated enough programming, computers would be able to achieve real understanding.
The Chinese Room thought experiment shows that one might be able to manipulate symbols and produce meaningful statements (by following a set of defined rules) without actually understanding the symbols or the statements. Searle does not rule out the possibility that it might one day be feasible to construct machines which could attain consciousness, thus being able to understand and to think, but insists that this has not yet happened, and cannot happen merely by any amount of increase in information-processing capability.
Peter Singer is one of the best known and most influential contemporary philosophers. He is most famous for his 1975 book, Animal Liberation, which argues that we have no rational basis for excluding non-human animals from our moral considerations.
Using utilitarianism as his ethical foundation, Singer’s work focuses primarily on applied ethics issues like abortion, euthanasia, and world poverty. He is widely criticized for many of his views, including his view that human infants lack personhood.
Singer maintains, in The Life You Can Save and other works, that comfortably off individuals in affluent societies are morally obliged to cut their living expenses down to subsistence and to donate most of their incomes to the relief of poverty. In the volume Singer Under Fire, Peter Singer responds to various attacks by critics.
Slavoj Žižek (1949)
A cultural critic, Marxist philosopher, and popularizer of philosophy, Slavoj Žižek garners a wide popular following and broad influence. His work focuses on ideology and argues that our unconscious motives are active in constructing reality.
Žižek writes widely and entertainingly on topics ranging from movies and pop culture to psychoanalysis and religion.