Ludwig Wittgenstein

In brief

Ludwig Wittgenstein (1889 to 1951) is the rare philosopher who built two systems, each of which reshaped a discipline, and who came to believe the second overturned the first. In the early work, the Tractatus Logico-Philosophicus (1921), he argued that language works by picturing states of affairs in the world: a meaningful sentence is a logical picture of a possible fact. From this he drew a severe conclusion. Anything that cannot be pictured, including ethics, the meaning of life, and the propositions of philosophy itself, cannot be meaningfully said. It can at most be shown. The book ends with its famous last line: whereof one cannot speak, thereof one must be silent.

The late work, gathered in Philosophical Investigations (published in 1953, two years after his death), tears down the picture theory. Meaning, the later Wittgenstein argued, is not a matter of words standing for things or picturing facts. The meaning of a word is its use in the ordinary human activities he called "language games," activities embedded in shared "forms of life." From this reorientation flow his most discussed arguments: that following a rule is a practice grounded in a community and not in a private mental act, and that a wholly private language, one whose words refer to sensations only the speaker can know, is impossible. Philosophy, on both views, is a kind of confusion produced by language idling. The two Wittgensteins disagreed about almost everything except that.

The life

Wittgenstein was born in Vienna in 1889 into one of the wealthiest families in the Austro-Hungarian Empire; his father Karl was a steel magnate, and the household was a center of Viennese cultural life, with Brahms and Mahler among its visitors. It was also marked by tragedy: three of Ludwig's four brothers died by suicide, and the fourth, Paul, became a concert pianist who lost his right arm in the First World War. Ludwig trained first as an engineer, studying aeronautics at Manchester, where work on the mathematics of propellers led him to the foundations of mathematics and logic. In 1911 he went to Cambridge to study with Bertrand Russell, who quickly judged him a genius and, within two years, came to feel the student had surpassed the teacher.

Wittgenstein wrote much of the Tractatus while serving in the Austrian army during the First World War, finishing it as a prisoner of war in Italy in 1918. He believed he had solved the problems of philosophy, and so he left the field. Through the 1920s he gave away his enormous inherited fortune, worked as a village schoolteacher in rural Austria, designed a spare modernist house in Vienna for his sister, and briefly considered becoming a monk. He was drawn back partly by conversations with members of the Vienna Circle, the logical positivists who read the Tractatus as their manifesto, and partly by the young Cambridge mathematician Frank Ramsey, whose criticisms he took seriously.

He returned to Cambridge in 1929 and began, slowly and against his own earlier convictions, to dismantle the picture theory. He later credited the economist Piero Sraffa with a decisive jolt: pressed by Wittgenstein to state the logical form of a proposition, Sraffa is said to have made a dismissive Neapolitan gesture with his fingertips and asked what the logical form of that was. Whatever the exact prompt, Wittgenstein came to see that the rigid, picturing account of language could not survive contact with the sprawling, context-bound ways people actually speak. He held the chair in philosophy at Cambridge from 1939, served as a hospital porter and lab assistant during the Second World War rather than sit out the emergency, resigned his professorship in 1947 to write, and died of prostate cancer in Cambridge in 1951. His last recorded words: tell them I have had a wonderful life. Philosophical Investigations, the work he could never bring himself to publish, appeared in 1953.

The full treatment

The problem both phases answer

Wittgenstein's lifelong subject was the relation between language and the world, and the way that relation goes wrong. His guiding conviction, held in both phases though pursued by opposite methods, was that most philosophical problems are not deep truths waiting to be discovered but confusions produced when language is wrenched out of its ordinary working. "Philosophy," he wrote in the Investigations, "is a battle against the bewitchment of our intelligence by means of language." The task is therapeutic: to dissolve the problem, not to solve it. What changed between the two books was his account of how language works, and therefore of how it misleads.

The picture theory of the Tractatus

The early Wittgenstein held that the world is the totality of facts, not of things, and that a proposition is meaningful when it is a logical picture of a possible fact. Just as a scale model of a car crash can represent the collision because its parts stand in the same relations as the parts of the real event, a sentence represents a state of affairs because it shares a logical structure with what it depicts. The elements of the sentence correspond to objects; their arrangement mirrors a possible arrangement of the world. A proposition is true if the fact it pictures obtains, false if it does not, and it is meaningful either way, because it lays out a possibility that can be checked against reality.

This yields a hard boundary. Only propositions that picture possible facts, in effect the propositions of natural science, say anything at all. Everything else falls outside the sayable. Logic and mathematics do not picture facts; they are tautologies, saying nothing about the world. Ethics and aesthetics concern value, which is not a fact in the world, so they cannot be put into words. And the propositions of the Tractatus itself are, by its own standard, nonsense: they try to say what can only be shown, namely the logical form that language and world share. Wittgenstein embraced this openly. His reader, he wrote, must recognize his propositions as nonsense once he has used them, and then throw away the ladder after climbing it. What cannot be said includes the very things he thought mattered most. Hence the closing injunction to silence, which was not a dismissal of ethics and the mystical but a way of protecting them from the corruption of bad talk.

The turn to use

The later Wittgenstein came to think the picture theory rested on a seductive mistake: the idea that every word must have a meaning by standing for some object, and every sentence must work by picturing. He opens the Investigations by quoting Augustine describing how he learned language as a child, by adults pointing at things and naming them. That picture, Wittgenstein argues, fits some words (proper names, perhaps) and is hopeless for most. What does "and" point at, or "hello," or "ouch"? Instead he offers a different image: think of a word as a tool, and its meaning as what you do with it. "For a large class of cases," he wrote, "the meaning of a word is its use in the language."

He introduces the term "language game" for the countless distinct activities in which words function: giving orders, describing, joking, thanking, cursing, praying, calculating, translating, guessing riddles. Each has its own rules, its own point, and there is no single essence they all share. To ask for the meaning of a word apart from any such activity, he suggests, is like asking what a chess piece means apart from the game of chess. This connects to his idea of "family resemblance." Ask what all games have in common and you will find no single feature, only a web of overlapping similarities, like the resemblances among members of a family. Many of our everyday concepts are like that, held together by overlap rather than by a shared definition. Language games are in turn woven into "forms of life," the shared practices and reactions that make the games possible and give them their sense.

The rule-following considerations

If meaning is use, and use is following the rules of a practice, then everything turns on what it is to follow a rule. Here Wittgenstein pressed a disquieting question. Suppose you have learned to continue the series 2, 4, 6, 8 and you write 10. What makes 10 the correct next step rather than, say, some deviant continuation? Any finite stretch of behavior is compatible with infinitely many rules. Whatever you point to, a mental image, a formula, a feeling of "now I can go on," can itself be interpreted in more than one way, so it cannot by itself fix the one correct continuation. Wittgenstein's response is that rule-following is not the private application of an interpretation at all. It is a practice, a custom, a habit trained into us and sustained by a community that agrees, in deed rather than in opinion, on how to go on. "To obey a rule," he wrote, "cannot be a private matter." There is no fact about your inner life that constitutes meaning addition rather than some deviant function; there is only the shared practice within which the question of correctness gets its sense.

The private language argument

From the rule-following considerations Wittgenstein draws his most famous single argument, running roughly from section 243 of the Investigations. Could there be a language whose words refer to inner sensations that only the speaker can know, and that in principle no one else could understand? Imagine keeping a diary in which you write the sign "S" every day you have a certain private sensation, a sign with no public definition and no outward criterion. Wittgenstein argues that "S" could never acquire a meaning. To use it correctly you would have to reidentify the same sensation on later days, but with nothing public to check against, there is no difference between correctly applying "S" and merely believing you have applied it correctly. "Whatever is going to seem right to me is right," he wrote, "and that only means that here we can't talk about right." Where no distinction between correct and incorrect use can get a grip, there is no rule, and so no meaning. His companion image is the beetle in a box: if everyone has a box, and calls whatever is in it a "beetle," but no one can look into anyone else's box, then the thing in the box drops out of the language altogether. What the word does is fixed by its public use, not by the private object it seems to name. The target is a whole Cartesian tradition, from Descartes onward, on which the mind is a private inner theater known first and best from within.

Lineage

Wittgenstein descends most directly from the logicist project of Gottlob Frege and Bertrand Russell, who had tried to reduce mathematics to logic and to expose the true logical form beneath surface grammar. Frege's distinction between the sense of an expression and its reference (see sense-and-reference) set the questions the young Wittgenstein worked on, and Russell's theory of descriptions modeled the ambition to dissolve philosophical puzzles by analyzing language. Behind them stands Immanuel Kant, whose Critique of Pure Reason tried to draw the limits of what thought can coherently claim; the Tractatus performs a parallel operation on language, marking the boundary of the sayable from the inside. The Socratic thread is also real: like Socrates, Wittgenstein takes definitional questions ("what is knowledge?", "what is a game?") as the engine of confusion, though he ends by rejecting the assumption that they have essence-revealing answers. The later philosophy fed directly into the ordinary language school at Oxford (Gilbert Ryle, J. L. Austin) and, through many hands, into the philosophy of mind, of mathematics, and of language for the rest of the century.

The strongest case for it

The enduring power of the later Wittgenstein is that he changed what a philosophical problem looks like. Before him, the natural move when facing a puzzle about meaning, mind, or knowledge was to posit a hidden mechanism: an inner object the word names, a mental act that grasps a rule, a private sensation that grounds a word. Wittgenstein showed, patiently and by example, how many of these mechanisms do no work, because the phenomenon they were invoked to explain is already fully accounted for by public practice. His treatment of sensation language reframed the philosophy of mind: it made vivid that "pain" is not learned by inspecting a private object but by being drawn into shared reactions and expressions, which is why we can be wrong about others but rarely doubt them in ordinary life. The rule-following considerations exposed a genuine gap that no amount of inner furniture fills, forcing later philosophers either to embrace the communitarian answer or to say precisely why they reject it. And the diagnostic method, treating philosophical theses as symptoms of linguistic confusion to be dissolved rather than as claims to be proved, remains a live and disciplined alternative to system-building. Even the early Tractatus, though he repudiated it, gave the Vienna Circle and analytic philosophy a model of rigor and a lasting worry about the limits of sense.

The strongest case against it

The objections are substantial and come from admirers as much as opponents.

The most influential is Saul Kripke's, in Wittgenstein on Rules and Private Language (1982). Kripke reconstructed the rule-following passages as a radical skeptical paradox: there is no fact, in my past behavior or my mind, that determines whether I meant addition or some deviant "quaddition" by "plus," and therefore no fact about what any word means. His "skeptical solution" is that meaning-talk is licensed not by facts but by a community's assertion conditions. Many scholars, including P. M. S. Hacker and Gordon Baker, argued that this "Kripkenstein" is closer to Kripke than to Wittgenstein, who they say never accepted the skeptical premise. The dispute itself is a mark against the texts: if careful readers cannot agree whether Wittgenstein even held the community view, the argument may be less determinate than its influence suggests.

A second line, pressed by Ernest Gellner in Words and Things (1959), charged the whole ordinary language movement with quietism and conservatism: by treating every established practice as beyond criticism ("this language game is played") and philosophy as leaving everything as it is, Wittgenstein risks turning philosophy into the mere description of usage, incapable of saying that a practice is confused or that ordinary talk itself embeds error. Science, after all, routinely overturns ordinary ways of speaking.

Third, philosophers of mind and language in the tradition of Jerry Fodor and Noam Chomsky reject the anti-theoretical stance outright. Chomsky's demonstration that linguistic competence rests on internalized computational structure, and Fodor's defense of a "language of thought," revive exactly the inner mechanisms Wittgenstein tried to banish, and they claim explanatory successes (in syntax, in acquisition) that pure appeal to public use cannot match. If the mind really does compute over inner representations, the private-language argument does not obviously touch it.

Finally, critics note that the private language argument, for all its fame, is stated so compressed that decades of debate have not settled what its premises even are, and that its conclusion, if fully general, sits uneasily with the plain fact that we do seem to know our own sensations more directly than anyone else's.

Where it stands now

Wittgenstein is, by most measures, the most influential philosopher of the twentieth century, and one of the most contested. The Tractatus remains a landmark of early analytic philosophy and a permanent reference point for questions about the limits of language. The Investigations reoriented the philosophy of mind and language, gave ordinary language philosophy its charter, and seeded fields as far apart as the anthropology of practice and the interpretation of scientific communities. The private language argument is still taught as a central result, even by those who think it fails, and the rule-following considerations remain a live problem that any serious theory of meaning must answer. The community-based reading is no longer dominant in the way it once was; naturalistic and computational programs have reclaimed much ground, and even sympathetic readers now argue over what Wittgenstein actually meant. But that is the shape of an idea that set the terms of debate. Philosophers still divide into rough camps by how they answer the questions he posed, which is the surest sign that the questions were the right ones.

Test yourself

Pick a word you are confident you understand: "game," "pain," or "know." Now try to state a definition that covers every correct use and excludes every incorrect one, without leaning on further words you would have the same trouble defining. If you cannot, notice that you still use the word without error every day. That gap, between what you can define and what you can do, is the whole of the later Wittgenstein. The meaning was never in the definition; it was in the doing.