Wittgenstein has been considered by many to be the greatest philosopher of the 20th Century. I think not. I am not sure that he was even a good philosopher, and one of the principal effects of his influence has been the largely sterile shambles to which 20th Century philosophy was reduced. This effect was not unlike what he actually wanted, since there was for him in fact little for philosophy to do except to undo the damage that philosophy had done by existing in the first place.
Wittgenstein crossed paths with the Friesian School in two minor but noteworthy ways. He was actually a relative of Friedrich A. Hayek. They happened to meet on a train station platform while both were serving in the Austrian Army in World War I. They did not know each other but seemed so familiar that they assumed they must be related. They were, in fact, cousins (Wittgenstein's maternal grandmother was the sister of Hayek's maternal great-grandfather). Wittgenstein's eldest sister (Hermine) was the contemporary and friend, as well as second cousin (like Ludwig), of Hayek's mother. The Wittgenstein family was wealthy, and 
there is a handsome painting of Wittgenstein's sister Margaret Stonborough-Wittgenstein by Gustav Klimt [shown; note]. Hayek did not have very much to do with them at the height of their fortunes, but after the war he heard about Ludwig occasionally through his mother, until he began encountering him at Cambridge. Wittgenstein himself gave up his share of the family inheritance, since he was not very interested in money and preferred to live simply.
There was not, of course, much in the way of a philosophical connection between Wittgenstein and Hayek -- only in their very last conversation, in 1949, did they begin to find some common political ground after Wittgenstein was shaken and disillusioned by the behavior of the Russians occupying Vienna. [See Hayek's "Remembering My Cousin Ludwig Wittgenstein (1889-1951)" in The Fortunes of Liberalism, Essays on Austrian Economics and the Ideal of Freedom, The Collected Works of F.A. Hayek, Volume IV, The University of Chicago Press, 1992, pp. 176-181].
There was not much of a philosophical connection either, between Wittgenstein and Karl Popper, but there was a famous and characteristic encounter between them, when Popper was invited to give a talk at the Cambridge "Moral Sciences Club" in 1946 (as recounted in his Unended Quest, An Intellectual Autobiography, Open Court, 1985, pp. 122-124). The talk rapidly turned into an argument between the two, with Wittgenstein making his characteristic claim that there are no philosophical problems, just confusions about language. Any number of problems that Popper cited were rejected, and finally, when Popper turned to problems of moral justification, Wittgenstein asked for an example of a moral rule. Since Wittgenstein had happened to pick up a poker from the fireplace and was waving it around while making his points (was this, as analytic philosophers like to say, "hand waving"?), the example Popper offered was, "Not to threaten visiting lecturers with pokers!" Wittgenstein then threw down the poker and stormed out of the room, slamming the door (the rumor quickly spread that they had even come to blows). After Popper finished his talk, R.B. Braithwaite approached him, with apologies, or perhaps congratulations, that Popper was "the only man who managed to interrupt Wittgenstein in the way in which Wittgenstein interrupted everyone else." Hayek, as it happens, had earlier seen Wittgenstein wielding the poker while correcting another speaker at Cambridge. His concerned impression was that the furious, indignant, and "rampant" philosopher was not quite sane. Hayek's description has led some to infer that he was at Popper's talk, but he wasn't. Wittgenstein's behavior seems to have been quite customary, and one of his students also later said that slamming the door didn't necessarily mean he was even angry. He just slammed doors all the time.
This example is revealing of a significant feature of Wittgenstein's life: It displays few of the customary features, in this case civilities (in general publications), that now are considered necessary and proper for an academic career. The trajectory began conventionally enough. Wittgenstein traveled to study in Britain as an engineering student. But, when his interests turned more to pure mathematics, and then to logic and the foundations of mathematics, he gave up engineering and went to study with Bertrand Russell instead. When World War I broke out, he returned to Austria to serve, as noted, in the Army. While on duty he wrote a book. When the War was over, he sent the manuscript to Russell, who decided that it would do as a doctoral dissertation. Considering the circumstances, this was perhaps not so extraordinary. Then Russell saw to it that the book was published -- as the Logisch-philosophische Abhandlung (1921, in German) and the Tractatus Logico-philosophicus (1922, in English). This became the only thing actually published by Wittgenstein in his entire lifetime. Since today a publication of nothing but one's dissertation, through the influence of a celebrated mentor, does not sound like (and could not possibly be) much of a career, it would not be surprising that Wittgenstein had no interest in a career, did not return to Britain, and instead busied himself with relatively humble tasks in Austria, including becoming an ordinary school teacher. What is surprising is the turn things took later.
The Tractatus is the essence of the "early" Wittgenstein. He apparently figured that it was all he ever needed to say in philosophy, until later he began changing his mind. The "later" Wittgenstein then leaves the Tractatus in an awkward position. It became a very popular work, the foundation of Wittgenstein's influence, and was still being read by many as his last word, even after he had long rejected it, since his newer ideas were not on the public record until after his death. The book is, indeed, one of the saddest monuments of modern philosophy, and perhaps one of the formative influences on one of the most miserable schools of modern philosophy, Logical Positivism. The fundamental principle for both was scientism, the notion that science encompasses all knowledge and can solve all "real" problems. The way the Tractatus expresses it is that the only meaningful statements are those made by science: "The totality of true propositions is the whole of natural science..." (Tractatus, translated by D.F. Pears & B.F. McGuinness, Routledge & Kegan Paul, 1961 & 1972, §4.11). The details that go with this, like Wittgenstein's logical atomism (i.e. that there are fundamental "atomic" statements that picture "atomic" facts in the world), or the development of truth tables, are by comparison of relatively minor importance. Thus, propositions of metaphysics, ethics, or religion are, strictly speaking, meaningless: "Philosophy is not one of the natural sciences" (§4.111). This became the inspiration and the lifeblood of the Positivists.
Wittgenstein himself, however, realized that there was a little problem with this. Were the propositions of the Tractatus itself statements made by science? Well, no. So they must be meaningless. Rather than trying to weasel out of this inconsistency, Wittgenstein decided to accept it and stated, "My propositions serve as elucidations in the following way: anyone who understands me eventually recognizes them as nonsensical..." (§6.54). This started another baleful tradition in modern philosophy, the approach of "edifying" or "therapeutic" philosophy, which denies that it really possesses knowledge or certainty, but nevertheless expects everyone to act as though it did possess knowledge and certainty -- or denies that philosophy does anything significant, or should exist, but nevertheless expects others to accept this school of philosophy as existing and significant, indeed decisive (the "end of philosophy"). So the Tractatus was like a ladder which, "He must, so to speak, throw away" (§6.54) once used to scale the heights. But what is at the heights?
The Positivists were not so eager to pronounce their own statements nonsense, though they were hopelessly caught in the same kind of inconsistencies, but it was a major part of the long appeal of the Tractatus that it made this admission. As Popper soon would say (in a long footnote to The Open Society and Its Enemies), if the Tractatus is useful and important nonsense, then why can't other kinds of nonsense, like metaphysics, be useful and important too? Indeed. Wittgenstein seemed to leave the door half-open to this by implying that there was, after all, other important stuff in life besides science, and that the value of the world cannot be in the world: "The sense of the world must lie outside the world....in it no value exists..." (§6.41). And while, "What we cannot speak about we must pass over in silence" (§7), it nevertheless looks like there is something there that one can be in touch with, somehow. To some this seemed like a positive endorsement of mysticism. Indeed, Wittgenstein actually says, "Feeling the world as a limited whole -- it is this that is mystical" (§6.45). Others thought that Wittgenstein might have had someone like Schopenhauer in mind, with things like the Will, art, and music expressing things that science and language could not. Since Wittgenstein rather liked music, a philosopher of music like Schopenhauer could have been appealing.
A distinctive feature of the Tractatus, apart from its doctrine, was simply its manner. The book consists of aphoristic, even Delphic, statements with little argument or exposition. This would seem to be a reversion to an earlier, pre-Parmenidean era of philosophy,
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(Matthew 7:28) And it came to pass, when Jesus had ended these sayings, the people were astonished at his doctrine: (7:29) For he taught them as one having authority, and not as the scribes. |
Wittgenstein had returned to philosophy in 1929. He was hired at Cambridge, of course, simply on the basis of his reputation as a genius, entirely based on the impression of the Tractatus and the influence of people like Russell. His career for the next twenty years, while conducted consistently on the assumption of that genius, nevertheless provided none of what now would be considered the indispensable evidence of it, i.e. publications. Wittgenstein told others what was what, and to an extraordinary degree people, whether they really believed that that was what really was what, actually accepted that it must nevertheless be important. It is hard to know what would be made of him now if his papers had been lost (or, in some fit of misosophy, he had destroyed them).
Whether or not Wittgenstein deserved this respect and privileged treatment, it must be cold comfort for those who tend to respect him most, when they are caught in (and have even helped create) a "publish-or-perish" academic system that would have had no place whatsoever for so unproductive, uncollegial, and domineering a person as Ludwig Wittgenstein. Indeed, Wittgenstein's detour into ordinary life during the 1920's, with nothing at all written beyond his dissertation, would now kill a career in academic philosophy more thoroughly than anything else. To be sure, the change in academia is due in great measure to the flood of subsidized philosophy degrees, and philosophy departments, created by post-World War II prosperity and the government-directed expansion of even esoteric or useless academic disciplines. The result has been bureaucracy and conformity, both deadly elements to eccentric and erratic characters like Wittgenstein. This has still got to be one of the most striking features of Wittgenstein's life as a philosopher: The whole "system" is now rigged against his kind.
After Wittgenstein's death, his papers were prepared for publication. First out were the Philosophical Investigations (Philosophische Untersuchungen, 1953), followed by Remarks on the Foundations of Mathematics (1956), The Blue and Brown Books (1958), and Notebooks 1914-1916 (1961). The Investigations revealed to the world the new "later" Wittgenstein. The scientism was gone, and the standard was now "ordinary language." Philosophy was still something that was basically superfluously troubled with unnecessary concerns over imaginary issues. Language was no longer something to represent a world of facts but a self-contained activity that determines itself. Languages, Wittgenstein famously decided, are "games"; and playing the particular language game is to engage in a certain "form of life." The rules of the language game are not determined by the nature of the world, but by the training provided by the corrections and example of other speakers. One cannot simply determine the truth for oneself, because it is not external reality, but the interaction with others that determines the correct statements. The role of this interaction rules out either a "private language" or an absolute truth independent of the standards of a linguistic community. Meaning, indeed, is just usage, and there are no independent senses which are to be matched up with reality to determine truth or falsehood. The theory of language is just a kind of human "natural history," describing one form of human behavior. [note]
This theory suffers from paradoxes very similar to those of the Tractatus. Does the Philosophical Investigations consist of ordinary language statements? Well, no. It consists of Wittgenstein's own, rather esoteric philosophical theory. The very feature of calling languages "games" is contrary to the usage of ordinary language -- a natural language, or even an artificial one, is not a game, even though games can be played with a language. What linguistic community has trained Wittgenstein in the standards that are expressed in the Philosophical Investigations? Well, none. Wittgenstein has made it all up himself, like any other original and creative philosopher. But it all is then, unfortunately, a private language. What is it that founds the truth of Wittgenstein's theory? Well, it is the matters of fact about language. But the foundation is then not just usage (certainly not Wittgenstein's unusual and original usage), but the meaning and reference of the theory, which Wittgenstein has figured out and discovered for himself. Thus, Wittgenstein's own discomfort, even hostility, towards others who disagree with him, his own solitary reflections and unique genius, all are falsifying counterexamples to his own theory. He cannot be a unique truth-finding genius on the basis of his own principles. The disagreement of others should be "training" him in the norms of the language of the community, and his solitary reflections are missing a "form of life" context in which alone meaningful statements can be generated.
The later Wittgenstein, however, can never acknowledge these paradoxes as could the Wittgenstein of the Tractatus. Wittgenstein himself can only be, and can be the only, prophetic and supernatural exception to his own arguments about meaning, linguistic community, and private language. The only refuge for subsequent Wittgensteinians, or those who have borrowed this nihilistic mode (e.g. Richard Rorty), is to disclaim any interest in knowledge, certainty, or truth, in favor of the "edifying" and "therapeutic" approach, whereby everyone is supposed to be dissuaded from caring about such things. The only compelling reasons, however, why one should be so dissuaded can only be in the form of reductio ad absurdum arguments against the theories of meaning and truth which the "therapists" oppose. If such arguments are successful, however, one would think that, given the forms of logic, this would have established the truth of whatever principles the "therapists" have that are contradicted by the objectionable principles of those other theories of meaning and truth. If their principles can thus be established, one would then have to ask why the paradoxes and incoherence of their theory does not then count as a reductio ad absurdum in turn?
In truth, they just don't care. They are happy to use logic against philosophers who take logic seriously, but they are not bound by any criteria of meaning or truth themselves, since they actually reject, for reasons that cannot be held up to logical rigor, any such criteria. Nevertheless, their reductio ad absurdum critique is bound to be taken seriously by the conscientious, even if its failure, or a logical turnabout, will effect no persuasion or enlightenment on its originators. Wittgenstein's arguments, like those of Protagoras, Pyrrho, or Hume, therefore enter into the mix of serious philosophy, even when we know that they will be productive of no positive results and represent no truly credible theory. Thus, it was once seriously put to me that Wittgenstein's entire linguistic philosophy was vindicated by no more than his paradox of "rule following." This is the sort of thing, then, that can be usefully addressed, despite the supremely paradoxical and incoherent nature of the theory it was (paradoxically) presumed to establish.
Wittgenstein's paradox of rule following is thoroughly addressed by Jerrold Katz in The Metaphysics of Meaning ("Wittgenstein on Rule Following," pp. 135-162). Wittgenstein says:
This was our paradox: no course of action could be determined by a rule, because every course of action can be made out to accord with the rule. The answer was: if everything can be made out to accord with the rule, then it can also be made out to conflict with it. And so there would be neither accord nor conflict here.... What this shews is that there is a way of grasping a rule which is not an interpretation, but which is exhibited in what we call "obeying the rule" and "going against it" in actual cases. [Philosophical Investigations, translated by G.E.M. Anscombe, Prentice Hall, 1958, §201, p. 81]
The point has two parts. The latter one is that following a rule is different from understanding it or talking about it. This is certainly true and is easily demonstrated when speakers of natural languages use the rules of those languages without even being aware of what they are, or claim that they follow rules of elevated usage ("Whom do you trust?") even when they actually persist in following common usage ("Who do you trust?"). This side of the matter is still somewhat paradoxical but already a familiar suggestion even in Plato. The former part of the point, however, is that there is no fact of the matter that would determine whether a rule is properly applied as we understand it. In other words, explicit, conscious application cannot do, because the truth of the matter cannot be determined, what implicit, tacit application can. This claim is the heart of a reductio ad absurdum, destructive paradox but rests on other arguments, arguments against essences and for the underdetermination of interpretation. "Essences" are rejected by Wittgenstein in favor of his nominalistic "family resemblance" theory, and the underdetermination of interpretation is promoted as revealing the determination of truth by linguistic usage rather than by objective reference. Such arguments are now the bread and butter of non-cognitive, deconstructive, and nihilistic philosophy. They are, however, simply false. In grammar it is altogether common to determine whether a course of action, an instance of usage, is to be "made out to accord with the rule" or not.
The principle of the underdetermination of interpretation may now be said to be a truth of hermeneutics. However, there is a profound difference between a relative and an absolute degree of underdetermination. If there are limits on ambiguity, then objective reference can be sufficient for interpretation. Also, Wittgenstein's argument unfortunately proves too much, for if there is nothing in objects to determine particular interpretations, then it is not clear how the speaker of a language is supposed to be aware of what is being corrected when he is (linguistically) corrected by another speaker who is training him in proper usage. Usage of what, about what? To correct a speaker, we must be able to recognize when usage is in accord with the linguistic rule or not. The statements made, and their external context, must, by Wittgenstein's theory, be subject to the same ambiguity and underdetermination as the original reference of the statements. This can be seen in training a dog. Unless the dog is rewarded or punished immediately for a particular behavior, it cannot know what the reward or punishment is about, and will merely become confused and upset. In Wittgenstein's world, where real objects and behavior cannot be denoted in the traditional sense, everyone would be in the situation of the dog who has lost the association of the moment.
Similarly, there is an element of truth in the "family resemblance" theory, which is that words cannot be unambiguously defined by clear and specific attributes, but that usage represents a train of associations which pass through one similarity after another. This reveals no hard core of meaning, an essence -- the sense that makes the thing what it is. The proper answer to this is "yes and no." There are such associations, and there are also clear attributes and definitions. Part of progress in mathematics, science, and philosophy is to propose or clarify such definitions. This issue in modern linguistics is wisely discussed by Steven Pinker in his Words and Rules, The Ingredients of Language [Basic Books, 1999]. Pinker points out that the brain uses rote memory (where recall is quick) for the fuzzy "resemblance" associations, but likes to simplify its task with clear rules in areas where the demands of rote memory would be prohibitive (with the recall delayed slightly by the application of the rule). His classic, paradigmatic example of the difference is the contrast between irregular and regular verbs. Irregular verbs betray all the stigmata of family resemblances, but regular verbs obey rules whose clarity and application are the falsifying counterexample to Wittgenstein's thesis.
Ironically, the Positivists, and perhaps even the Wittgenstein of the Tractatus, condemned natural language for its ambiguities and looked forward to artificial languages where words would have only one clear-cut meaning. This was impossible, since the metaphorical applications that people spontaneously originate would immediately begin changing any such meanings. In rejecting the Tractatus and Positivism, however, Wittgenstein merely went to the opposite extreme, where there are no unambiguous meanings whatsoever. This is part of the mystery of the appeal of Wittgenstein, why it was so difficult for 20th Century philosophy to recognize that both extremes hold an element of truth, even while that promoted by the later Wittgenstein makes nonsense of a great deal of what mathematics, science, and philosophy try to do in clarifying concepts and principles. As with Wittgenstein himself, it is hard not to conclude that a lot of people in philosophy actually don't like philosophy all that much, or at least don't expect to get all that much out of it.
Curiously, part of Wittgenstein's argument against essences and for the underdetermination of interpretation uses an example from mathematics.
What really comes before our mind when we understand a word? -- isn't it something like a picture? Can't it be a picture?Well, suppose that a picture does come before your mind when you hear the word "cube", say the drawing of a cube. In what sense can this picture fit or fail to fit the use of the word "cube"? -- Perhaps you say: "It's quite simple; -- if that picture occurs to me and I point to a triangular prism for instance, and say it is a cube, then this use of the word doesn't fit the picture." -- But doesn't it fit? I have purposely so chosen the example that it is quit easy to imagine a method of projection according to which the picture does fit after all.
The picture of the cube did indeed suggest a certain use to us, but it was possible for me to use it differently. [ibid., §139, p. 54]
This 
entire passage begs the question, for it is not by means of a "picture" (a theory carried over from the Tractatus) that anything is understood. Only the very crudest Empiricism would have it so. This gives Wittgenstein's demonstration no more force that Locke's refutation of "innate ideas" by way of his own definition of "ideas" as images. A "triangular prism" may be the projection of a cube, but then every "drawing of a cube" is a projection of a cube. In fact, nothing drawn on a flat surface can be a cube, which is a three dimensional object. We tend to identify a drawing like the one at right as a cube because we in fact see things by means of two dimensional projections, onto the retina.
No such drawing or projection has anything to do with the meaning of "cube," which is not and cannot be defined by means of drawings. Wittgenstein's argument only demonstrates that meanings are not pictures.
Katz (pp. 139-141) realizes that the ambiguity and underdetermination that Wittgenstein sees in an "essentialistic" view of meaning is due to his confusion between the abstract nature of actual meaning and the concrete nature of the images, etc. through which Wittgenstein chooses to construe "essentialism." Since a concrete object cannot be defined as an individual by even an infinite number of abstract predicates, it is not surprising, as I have heard in one version of Wittgenstein's rule following argument, that it is impossible to specify all the rules to explain a particular usage of a word. Well, yes, but then that is not necessary. The full specificity of any usage is, in the best Aristotelian terms, accidental.
Wittgenstein's popularity may be explained by the skepticism and nihilism that still reign in modern philosophy, even sometimes in awkward conjunction with scientism. Perhaps it is natural enough, for people who can't think of anything new to explain the nature of knowledge, to retreat into views that it cannot be explained and that knowledge in the traditional sense simply doesn't exist (or only exists, in some form, in science). This attitude, interestingly, does not seem to exist in science itself, where problems and mysteries are taken as challenges, rather than as discouragements, and where most expect someone eventually to propose theories to deal with them. This sanguine expectation is rather rare in philosophy, where the demands on the imagination are relatively greater and where not much new in the way of observational data can be said to have been produced. Philosophers often seem in a surprising hurry to end philosophy, not just because they think they have discovered the truth, but because the enterprise is to be shown as flawed, futile, or mistaken.
Wittgenstein, on the other hand, acted more like a traditional philosopher than one would expect from his theory. He seems to have expected treatment like a solitary creative genius, and he was so treated. He gave up philosophy at one point because he had said everything, but then he came back and had considerably more to say. He proposed a theory that meaning only existed in relation to the usage of a linguistic community, but then he always went his own way, kept his own counsel, and was often in positive conflict with those who disagreed. In all this, as in so much of life, it seems wiser to note what he did, not what he said.
The Getty Center Museum contains a 
portrait with the name Wittgenstein: Leonilla, Princess of Sayn-Wittgenstein-Sayn by Franz Xaver Winterhalter (1843). I have not seen any explanation of the connection of "Sayn-Wittgenstein-Sayn" to Ludwig Wittgenstein's family, but the Princes of Sayn-Wittgenstein seem to have been from an old Rhineland family. There is some information on the Web about Sayn Palace, rebuilt by Prince Ludwig Adolph Friedrich and Leonilla.
In linguistics, the idea that language, rather than reality, determines truth is associated with Edward Sapir and Benjamin Lee Whorf. Their idea was mainly that grammar provides the structure which is attributed to the world. Languages do have significantly different systems of grammar, and Whorf was fascinated with the grammar of isolated languages like Hopi. However, the burden of meaning about the nature of the world in languages is largely carried by vocabulary. Grammar doesn't prevent statements about reality with the relevant vocabulary. Since vocabulary is easily borrowed from one language to another (as from Greek and Latin into English, or from Arabic and Persian into Turkish, or from Chinese into Korean, Vietnamese, and Japanese), it becomes difficult to argue that something about a particular language determines the nature of the world.
Indeed, the difference between grammar and vocabulary creates an important ambiguity in Wittgenstein's idea of language. Since vocabulary can be borrowed, or coined, and any proposition can be expressed as an affirmative or negative, a natural language is a very flexible instrument that radically underdetermines truth. A "language" that determines truth, as part of a language "game" and a "form of life," thus means a particular vocabulary and the particular paradigm (in Kuhn's terms) that a certain community, using the vocabulary, endorses. This is the sense in which Wittgenstein ends up himself with a private language, since it is his own, and not anyone else's, vocabulary and paradigm that he uses.