Analytic Philosophy

Analytic philosophy is the tradition that grew out of new work in logic and mathematics in Germany and Britain around 1900 and went on to dominate university philosophy in the English-speaking world. Its founders believed that many old philosophical problems arose from confusion about language and logic, and that careful analysis of what sentences mean, and of how arguments work, could either solve those problems or show them to be empty. The tradition has never had a single doctrine. What its members have shared is a style: short, precise arguments, attention to logic and to the sciences, and a habit of stating a thesis plainly enough that someone else can try to refute it.

The movement began in a handful of places, the small German university town of Jena, Cambridge, Vienna and the Polish universities of Lviv and Warsaw, and it was scattered across the Atlantic by the rise of Nazi Germany. By the 1950s it was the normal way of doing philosophy in Britain, the United States, Australia and Scandinavia, and today it is practised worldwide. It follows on from nineteenth-century philosophy, partly as a revolt against it, and it grew up alongside continental philosophy, the other great twentieth-century tradition, from which it gradually drew apart.

The story usually begins with Gottlob Frege, a mathematician who taught at Jena from 1874 until 1918 and was little read in his lifetime. In the Begriffsschrift of 1879, whose title means roughly concept-script, he invented modern symbolic logic. The logic inherited from Aristotle dealt well with sentences such as "all men are mortal" but could not handle sentences that combine several generalities, such as "every number has a successor". Frege's notation, with its quantifiers for "all" and "some", could express such claims and make every step of a mathematical proof explicit.

His aim was to show that arithmetic is nothing but logic: that numbers and their laws can be defined from purely logical notions. In doing so he developed a philosophy of language that still frames the subject. In On Sense and Reference (1892) he observed that "the Morning Star is the Evening Star" tells us something new, while "the Morning Star is the Morning Star" does not, although both names pick out the same object, the planet Venus. He concluded that a name has both a reference, the thing it stands for, and a sense, the way it presents that thing. He also insisted that the meaning of a word should be sought in its contribution to the sentences in which it occurs, and that logic concerns objective thoughts, not the psychology of individual minds.

In 1902, as the second volume of his Basic Laws of Arithmetic went to press, Frege received a letter from a young Englishman pointing out that one of his axioms led to a contradiction. The project as he had designed it could not be saved, and Frege, by his own account, was deeply shaken.

The Englishman was Bertrand Russell, a fellow of Trinity College, Cambridge. His paradox concerns the set of all sets that are not members of themselves: if it is a member of itself, it is not, and if it is not, it is. Russell spent the next decade trying to rebuild the foundations of mathematics without such contradictions, and with Alfred North Whitehead he produced the three volumes of Principia Mathematica (1910–1913), a monument of formal logic that proves, after hundreds of pages, that one plus one equals two.

At the time British philosophy was dominated by idealists, followers of Hegel such as F. H. Bradley, who held that reality is ultimately a single spiritual whole and that ordinary distinctions between things are partial and misleading. Russell's Cambridge friend G. E. Moore led the rebellion. In The Refutation of Idealism (1903) and later essays he defended common sense, arguing that he knew with more certainty that he had two hands than he could ever know any philosophical premise that implied otherwise. His Principia Ethica, also of 1903, argued that goodness is a simple property that cannot be defined in terms of anything natural, such as pleasure, and it became a sacred text for the Bloomsbury group of writers and artists in London.

Russell's paper On Denoting (1905) became the model of what analysis could do. A sentence such as "the present King of France is bald" seems to be about something that does not exist. Russell showed that it can be rewritten as a claim that there is exactly one present King of France and that this person is bald, a claim that is simply false. The puzzle disappears once the hidden logical form of the sentence is revealed beneath its grammar. This idea, that ordinary grammar can mislead and that logic shows what a sentence really says, guided the movement for decades.

Ludwig Wittgenstein, the youngest son of one of the richest industrial families in Austria-Hungary, came to Cambridge in 1911 to study with Russell after training as an engineer in Berlin and Manchester. Within a year Russell regarded him as his successor. Wittgenstein served in the Austro-Hungarian army in the First World War, and by the end of the war he had completed the only book of his published in his lifetime, the Tractatus Logico-Philosophicus, whose manuscript he carried into an Italian prisoner-of-war camp.

The Tractatus is a sequence of numbered remarks. It argues that the world consists of facts, that a meaningful sentence is a kind of logical picture of a possible fact, and that the propositions of logic are tautologies that say nothing about the world. From this it follows that ethics, aesthetics, religion and philosophy itself cannot be put into meaningful sentences at all. The book ends with the instruction that what cannot be spoken about must be passed over in silence. Believing he had solved the problems of philosophy, Wittgenstein gave the subject up and worked as a village schoolteacher in Lower Austria.

In 1922 the physicist and philosopher Moritz Schlick took up a chair in Vienna, and a discussion group formed around him that included the economist and social reformer Otto Neurath, the mathematician Hans Hahn and, from 1926, the German logician Rudolf Carnap. The young Kurt Gödel attended, and in 1931 published his incompleteness theorems, which showed that no consistent formal system rich enough for arithmetic can prove all arithmetical truths. A sister group gathered in Berlin around Hans Reichenbach, and the Lwów–Warsaw school in Poland, whose best-known member was Alfred Tarski, developed logic and the theory of truth in parallel.

The Circle read the Tractatus closely and drew from it, and from the physics of Albert Einstein, a programme known as logical positivism or logical empiricism. Its centre was the verification principle: a statement is meaningful only if it is either true by definition, as in logic and mathematics, or capable in principle of being checked by experience. Statements about the Absolute, the soul or the nothing were therefore neither true nor false but meaningless. In 1929 the group published a manifesto, The Scientific Conception of the World, which tied this scientific outlook to the social-democratic politics of interwar "Red Vienna". Carnap's Logical Construction of the World (1928) tried to show how all knowledge could be built up from elementary experiences.

The English philosopher A. J. Ayer visited Vienna and spread the doctrine in Language, Truth and Logic (1936), a brisk book that also argued that moral judgements merely express feelings of approval or disapproval. The movement's own critics noted that the verification principle itself seemed to be neither a definition nor an empirical claim, and versions of it grew steadily weaker. The political setting proved fatal. In 1936 Schlick was shot dead on a staircase of the university by a former student, a killing that some in the city's press excused in antisemitic terms, and after the annexation of Austria in 1938 the Circle was gone. Carnap went to Chicago, Reichenbach to Los Angeles, Neurath to the Netherlands and then England, and Gödel to Princeton. Their emigration, along with that of many other refugees from the Holocaust, shifted the centre of gravity of the tradition to America.

Karl Popper, a Viennese schoolteacher on the edge of the Circle, rejected its central idea. In Logik der Forschung (1934) he argued that no number of observations can verify a universal law, since the next observation might always contradict it, but that a single counter-example can refute one. What marks a theory as scientific is therefore falsifiability: it must forbid something, and so risk being proved wrong. Einstein's general relativity, which predicted a precise bending of starlight confirmed during the 1919 eclipse, was his model of a bold, risky theory. Psychoanalysis and the Marxism of his youth, which seemed able to explain any outcome, were his examples of theories that could not fail and so told us nothing.

Popper spent the war in New Zealand, where he wrote The Open Society and Its Enemies (1945), an attack on Plato, Hegel and Marx as intellectual ancestors of totalitarianism and a defence of piecemeal, testable reform. He then taught at the London School of Economics. The philosophy of science he helped found was later reshaped by Thomas Kuhn's Structure of Scientific Revolutions (1962), which described science as long periods of normal work within a paradigm broken by revolutions, and by Imre Lakatos and Paul Feyerabend.

Wittgenstein returned to Cambridge in 1929, became professor in 1939, and came to reject much of the Tractatus. The notes he worked on until his death in 1951 were published as the Philosophical Investigations in 1953. Language, he now argued, does not have one essence, such as picturing facts. It is a collection of activities, which he called language games, woven into human life: giving orders, telling jokes, describing objects, praying. The meaning of a word is in most cases its use in such a practice. The many things called games share no single feature, only a network of overlapping similarities, which he called family resemblances. His private language argument suggested that words for sensations such as pain cannot get their meaning from a purely inner act of naming, which challenged the picture of the mind inherited from Descartes. Philosophical problems arise, he wrote, when language goes on holiday, and the philosopher's task is to cure such confusions, not to build theories.

A related movement flourished in Oxford after the Second World War. Gilbert Ryle's The Concept of Mind (1949) mocked the Cartesian view of the mind as a ghost in the machine and argued that talk of minds is talk of how people behave and are disposed to behave. J. L. Austin studied the fine distinctions of everyday speech and, in lectures published as How to Do Things with Words (1962), pointed out that many utterances, such as "I promise" or "I name this ship", do not describe anything but perform an act. P. F. Strawson challenged Russell's theory of descriptions in On Referring (1950) and later revived metaphysics as the description of the basic structure of our thought. Paul Grice explained how speakers communicate more than they literally say, through what he called implicature. Ordinary language philosophy faded by the 1970s, but its ideas about speech acts and meaning passed into linguistics.

The leading American figure of mid-century was W. V. O. Quine of Harvard, near Boston, who had met the Vienna Circle in 1932–33 and admired Carnap. In Two Dogmas of Empiricism (1951) he attacked the positivists' distinction between analytic truths, true by meaning alone, and synthetic truths, true because of the world. He argued that no sentence is immune from revision: our beliefs face experience as a whole, like a web, and even logic could in principle be changed to accommodate surprising data. Philosophy for Quine was continuous with science, not a separate discipline above it, and in Word and Object (1960) he argued that translation between languages is always underdetermined by the evidence.

Quine's influence helped revive questions the positivists had dismissed. In lectures given at Princeton in 1970 and published as Naming and Necessity (1980), Saul Kripke argued that proper names refer directly, not through descriptions, and that some truths, such as that water is H2O, are necessary even though they were discovered by experience. David Lewis defended the view that other possible worlds are as real as our own. Hilary Putnam argued that meaning depends partly on the environment, so that the word "water" would mean something different on a planet where an identical-looking liquid had a different chemistry. Edmund Gettier's three-page paper of 1963 showed that a justified true belief can still fall short of knowledge, setting epistemology a puzzle it has argued about ever since. By the 1970s analytic philosophy had become less a method of dissolving problems than a broad enterprise of constructing theories about language, knowledge, metaphysics and value.

Few subjects changed more than the study of mind. After Ryle's behaviourism, U. T. Place in 1956 and J. J. C. Smart in 1959, both working in Australia, proposed that mental states simply are brain states, as lightning simply is electrical discharge. Putnam and others replied that the same mental state, such as pain, might be realised in very different physical systems, and proposed functionalism: a mental state is defined by what it does, its causes and effects, not by what it is made of. That view fitted the computer age opened by Alan Turing, whose paper of 1950 asked whether machines can think and proposed an imitation test to decide it.

Critics argued that something was being left out. Thomas Nagel's essay What Is It Like to Be a Bat? (1974) held that the subjective character of experience escapes physical description. John Searle's Chinese room argument (1980) imagined a person who follows rules for manipulating Chinese symbols without understanding a word, and concluded that running a program is not enough for understanding. Frank Jackson imagined a scientist who knows every physical fact about colour but has never seen red. In the 1990s David Chalmers named the hard problem of consciousness, why any physical process is accompanied by experience at all, while Daniel Dennett and Paul and Patricia Churchland argued that the problem would dissolve as neuroscience advanced. Since the 2020s large language models have given these old thought experiments a new and practical urgency.

Logical positivism had left little room for ethics, and in the 1950s it was common to say that political philosophy was dead. Its revival came from several directions. In Modern Moral Philosophy (1958) Elizabeth Anscombe, Wittgenstein's student and translator, attacked the moral theories of her day and urged a return to the ethics of virtue. She, Philippa Foot, Iris Murdoch and Mary Midgley, who had studied together at Oxford during the war, did much to bring character and human nature back into ethics; Foot also devised the trolley problem in 1967. Peter Singer's Famine, Affluence, and Morality (1972) argued that people in rich countries are obliged to give much more to relieve distant suffering, and his Animal Liberation (1975) helped start a social movement.

The decisive book was A Theory of Justice (1971) by John Rawls of Harvard. Rawls revived the social contract of Locke, Rousseau and Kant as a thought experiment. Imagine choosing the basic rules of society from behind a veil of ignorance, not knowing whether you will be rich or poor, talented or not, of which race, sex or religion. Rational people in this original position, he argued, would choose two principles: equal basic liberties for all, and a rule that social and economic inequalities are permitted only if they benefit the least advantaged, the difference principle. The book was a reply to the utilitarianism of John Stuart Mill, which Rawls thought could justify sacrificing some people for the greater total good.

A Theory of Justice provoked a generation of debate. Robert Nozick's Anarchy, State, and Utopia (1974) defended a minimal state and argued that taxation for redistribution violates rights of ownership. Communitarians such as Michael Sandel, Alasdair MacIntyre and Michael Walzer objected that Rawls's chooser was an abstract self stripped of the communities that give people their identities. Amartya Sen and Martha Nussbaum developed the capabilities approach, which measures justice by what people are actually able to do and be. Rawls himself, in Political Liberalism (1993), asked how citizens divided by deep religious and moral disagreement can still share a fair political order.

Feminist philosophers had long worked largely outside the analytic mainstream, drawing on Mary Wollstonecraft, Simone de Beauvoir and the women's movement. From the 1980s a group of philosophers began to use the tools of analytic philosophy for feminist ends, and in doing so changed those tools. Susan Moller Okin's Justice, Gender, and the Family (1989) pointed out that Rawls and his critics had largely taken the family for granted, though it distributes work, money and power unequally, and argued that a just society must include just households.

Others turned the methods of philosophy of language and epistemology on gender itself. Rae Langton, drawing on Austin's theory of speech acts, argued that pornography could be understood as an act that subordinates women and silences their speech, not merely as speech about them. Sally Haslanger proposed defining gender and race as positions in social hierarchies, not natural kinds, and asked what concepts of them people ought to adopt for the purposes of justice. Miranda Fricker's Epistemic Injustice (2007) identified the wrong done to someone when they are disbelieved because of prejudice about who they are. The Jamaican-born philosopher Charles Mills, in The Racial Contract (1997), argued in a similar spirit that the social contract tradition had always contained an unspoken agreement among white people to exclude others. Work on oppression, testimony and the social construction of categories is now part of the analytic mainstream.

The tradition that once tried to abolish metaphysics now houses a flourishing metaphysics of possibility, causation, time and persons. Its centres are no longer only Oxford, Cambridge and Harvard but universities across North America, Europe, Australia, Latin America and Asia. Specialised fields have multiplied: the philosophy of physics, biology and cognitive science, formal epistemology using probability theory, and applied ethics in medicine, technology and the environment. Experimental philosophers test the intuitions on which arguments rely by surveying ordinary people, and conceptual engineers ask not only what our concepts mean but how they should be improved. Effective altruism, which grew from Singer's arguments and from Oxford philosophers in the 2010s, has carried analytic ethics into charitable giving and policy. The ethics and philosophy of artificial intelligence have become a major field in their own right.

The once sharp boundary with continental philosophy has also softened, as analytic philosophers have turned to Husserl, Heidegger and Hegel, and to traditions such as Chinese, Indian and African philosophy, with the same expectation of clear argument that Frege brought to arithmetic. For the wider sequence of eras this tradition belongs to, see the history of philosophy overview.