Wittgenstein, Ludwig

Ludwig Wittgenstein
Photographed by Ben Richards in Swansea, Wales in 1947
Born	April 26, 1889(1889-04-26) Vienna, Austria-Hungary
Died	April 29, 1951(1951-04-29) (aged 62) Cambridge, United Kingdom
Cause of death	Prostate cancer
Resting place	Ascension Parish Burial Ground, Cambridge Coordinates: 52°13′03″N 0°06′00″E / 52.2176°N 0.1001°E / 52.2176; 0.1001
Education	PhD (Cantab)
Alma mater	Berlin Technische Hochschule; Victoria University of Manchester; University of Cambridge
Occupation	Philosopher, schoolteacher, soldier, gardener
Known for	Private language argument, language-game, family resemblance, picture theory of language
Notable works	Tractatus Logico-Philosophicus (1921) Philosophical Investigations (1953)
Parents	Karl Wittgenstein and Leopoldine Kalmus
Relatives	Paul Wittgenstein (brother), Margaret Stonborough-Wittgenstein (sister)
Website
The Cambridge Wittgenstein archive

Ludwig Josef Johann Wittgenstein (26 April 1889 – 29 April 1951) was an Austrian-born philosopher who held the professorship in philosophy at the University of Cambridge from 1939 until 1947.^[1]

Described by Bertrand Russell as "the most perfect example I have known of genius as traditionally conceived, passionate, profound, intense, and dominating," Wittgenstein inspired two of the century's principal philosophical movements, logical positivism and ordinary language philosophy, though in his lifetime he published just one book review, one article, a children's dictionary, and the 75-page Tractatus Logico-Philosophicus (1921)—25,000 words of philosophical writing published when he was alive, and three million unpublished. Professional philosophers have ranked his posthumously published Philosophical Investigations (1953) as the most important book of 20th-century philosophy.^[2]

Born into one of Austria-Hungary's wealthiest families in Vienna at the turn of the century, he gave away his massive inheritance, and subsequently worked as a teacher and gardener, serving on the front-lines during the First World War and being commended by the Austrian army for his courage and sang-froid. He was homosexual, as was at least one of his brothers, three of whom committed suicide, with Wittgenstein and the remaining brother contemplating it too. Those who knew him described him as tortured and domineering: Richard Rorty writes that he took out his intense self-loathing on everyone he met. He grew angry when any of his students wanted to pursue philosophy, and famously embraced the wife of philosopher G.E. Moore when he learned she was working in a jam factory—doing something useful, in Wittgenstein's eyes.^[3]

His work is usually divided between his early period, exemplified by the Tractatus, and his later period, articulated in the Investigations. The early Wittgenstein was concerned with the relationship between propositions and the world, and saw the aim of philosophy as correcting misconceptions about language through logical abstraction. The later Wittgenstein rejected many of the conclusions of the Tractatus, and provided a detailed account of the many possible uses of ordinary language, calling language a series of interchangeable language-games in which the meaning of words is derived from their public use. Despite these differences, similarities between the early and later periods include a conception of philosophy as a kind of therapy, a concern for ethical and religious issues, and a literary style often described as poetic. Terry Eagleton called him the philosopher of poets and composers, playwrights and novelists.^[4]

[edit] Background

[edit] The Wittgensteins

Karl Wittgenstein was one of the richest men in Austro-Hungary.^[5]

According to a family tree prepared in Jerusalem after the Second World War, Wittgenstein's paternal great-grandfather was Moses Meier, a Jewish land agent who lived with his wife, Brendel Simon, in Bad Laasphe in the Principality of Wittgenstein, Westphalia.^[6] In July 1808 there was a Napoleonic decree that Jews must adopt an inheritable family surname, and so Meier's son, also Moses, took the name of his employers, the Sayn-Wittgensteins, and became Moses Meier Wittgenstein.^[7] His son, Hermann Christian Wittgenstein—who took the middle name "Christian" to distance himself from his Jewish background—married Fanny Figdor, also Jewish, who converted to Protestantism just before they married, and the couple went on to found a successful business trading in wool in Leipzig, far from their Jewish origins.^[8] Ludwig's grandmother, Fanny Figdor, was a first cousin of the famous violinist Joseph Joachim.^[9] They had 11 children—all forbidden by Hermann to marry Jews—among them Wittgenstein's father, Karl, who by the late 1880s was one of the richest men in the Austro-Hungarian empire, with a fortune in iron and steel.^[5] Thanks to Karl, the Wittgensteins became the Austrian equivalents of the Krupps or Rothschilds; as a result of his decision in 1898 to transfer all his investments overseas, the family was shielded from the hyperinflation that hit Austria after World War I.^[10]

[edit] Early life

Ludwig's sister Margaret, painted by Gustav Klimt for her wedding portrait in 1905.

Wittgenstein was born to Karl and his wife, Leopoldine Kalmus—Jewish on her father's side and Roman Catholic on her mother's—at 8:30 in the evening on 26 April 1889 in the Palais Wittgenstein at Alleegasse 16, now the Argentinierstrasse, near the Karlskirche.^[11] Karl and Poldi, as she was known, had nine children in all. There were four girls: Hermine, Margaret (Gretl)—who was analysed by Sigmund Freud in the early 1930s—Helene, and a fourth daughter who died as a baby; and five boys: Johannes (Hans), Kurt, Rudolf (Rudi), and Paul, who became a concert pianist despite losing an arm in the war, and for whom Maurice Ravel wrote his Piano Concerto for the Left Hand. Ludwig was the youngest of the family.^[12]

The children were baptized as Catholics, and raised in an exceptionally intense environment. The family sat at the center of Vienna's cultural life, with Bruno Walter describing life at Palais Wittgenstein as an "all-pervading atmosphere of humanity and culture."^[13] Karl was a leading patron of the arts, commissioning works by Auguste Rodin and financing the city's exhibition hall and art gallery, the Secession Building. Gustav Klimt painted Wittgenstein's sister for her wedding portrait, and Johannes Brahms and Gustav Mahler gave regular concerts in the family's numerous music rooms, though Alexander Waugh writes that the firstborn, Hermine, was so nervous of Brahms that, when once invited to sit with him at dinner, she spent most of the evening vomiting in one of the bathrooms.^[14]

[edit] Brothers' suicides

From left, Helene, Rudi, Hermine, Ludwig (the baby), Gretl, Paul, Hans, and Kurt, around 1890.

Karl's aim was to turn his sons into captains of industry. Ray Monk writes that they were not sent to school lest they acquire bad habits, but were educated at home to prepare them for work in Karl's business empire.^[15] Instead, three of them committed suicide, Paul became a concert pianist, and Wittgenstein a philosopher after a brief period as an engineer.^[16] The Irish psychiatrist Michael Fitzgerald argues that Karl was a harsh perfectionist who lacked empathy, and that Wittgenstein's mother was anxious and insecure, unable to stand up to her husband.^[17]

Whatever the reason, the family had a strong streak of depression running through it, or what Anthony Gottlieb called bad temper and extreme nervous tension. He tells a story about Paul practicing one day on one of the family's seven grand pianos. He leapt up and shouted at Wittgenstein in the next room: "I cannot play when you are in the house, as I feel your skepticism seeping towards me from under the door!"^[18] Fitzgerald and the Swedish psychiatrist Christopher Gillberg argue that Wittgenstein showed several features of high-functioning autism; German psychiatrist Sula Wolff suggests he suffered from schizoid personality disorder.^[17]

Ludwig (bottom-right), Paul, and their sisters, late 1890s.

The eldest brother, Hans, may also have suffered from autism. Alexander Waugh writes that the boy's first word was "Oedipus". At the age of four, Waugh writes, Hans could identify the Doppler effect in a passing siren as a quarter-tone drop in pitch, and at five started crying "Wrong! Wrong!" when two brass bands in a carnival played the same tune in different keys. He was hailed as a musical genius, and was probably gay; he died in mysterious circumstances in May 1902, when he ran away to America then disappeared from a boat in Chesapeake Bay, likely a suicide.^[19]

Exactly a year later, aged 22 and studying chemistry at the Berlin Academy, his brother Rudi walked into a bar on the Brandenburgstrasse, asked the pianist to play Thomas Koschat's "Verlassen, verlassen, verlassen bin ich," then mixed himself a drink of milk and potassium cyanide, dying in agony. He left several suicide notes, one to his parents that said he was grieving over the death of a friend, and another that referred to his "perverted disposition." It was reported at the time that he had sought advice from the Scientific-Humanitarian Committee, an organization that was campaigning against Paragraph 175 of the German Criminal Code, which from 1871 until 1969 forbade homosexual sex. His father forbade the family from ever mentioning his name again.^[20]

Kurt did become a company director briefly, but shot himself on 27 October 1918 at the end of the First World War, when the Austrian troops he was commanding refused to obey his orders and deserted en masse.^[21] Gottlieb writes that Hermine had said Kurt seemed to carry "the germ of disgust for life within himself." Paul also considered suicide, as did Wittgenstein.^[18] He told a friend, David Pinsent, that when Bertrand Russell first encouraged him in his philosophy in January 1912, it had ended nine years of loneliness and wanting to die, though Russell was so worried about his state of mind that he predicted Wittgenstein would kill himself by February 1914.^[22]

[edit] 1903–1906: Realschule in Linz

[edit] School years

The Realschule in Linz.

After the deaths of Hans and Rudi, Karl relented, and allowed Paul and Wittgenstein to be sent to school. Alexander Waugh writes that it was too late for Wittgenstein to pass his exams for the more academic Gymnasium in Wiener Neustadt; he failed his entrance exam and only barely managed after extra tuition to pass the exam for the more technically oriented K.u.k. Realschule in Linz, a small state school with 300 pupils, and according to Brian McGuinness a stronghold of German nationalism.^[23] In 1903, when he was 13, he began three years of schooling there, lodging nearby in term time with the family of a Dr Srigl, a master at the local gymnasium, the family giving him the nickname Luki.^[24]

Historian Brigitte Hamann writes that he stood out from the other boys and was bullied; he spoke an unusually pure form of High German with a stutter, dressed elegantly, and was sensitive and unsociable.^[25] His first impressions of the school, recorded in fragmentary form in a notebook, indicate there may have been an early romantic relationship with Dr. Stigl's son, Pepi, who died in August 1914: "Mist! [Rubbish!] Relation to the Jews. Relation to Pepi. Love and pride. Knocking hat off. Break with P. Suffering in class."^[24]

According to Waugh, Wittgenstein was a misfit at the school, insisting the other children address him with the formal German "Sie", and was often absent.^[23] The other boys made fun of him, singing after him: "Wittgenstein wandelt wehmütig widriger Winde wegen Wienwärts" ("Wittgenstein wends his woeful windy way Vienna-wards").^[26] In his leaving certificate, he received a top mark only once, in religious studies; a 2 for conduct and English, 3 for French, geography, history, mathematics and physics, and 4 for German, chemistry, geometry and freehand drawing. He had particular difficulty with spelling and failed his written German exam because of it. He wrote in 1931: "My bad spelling in youth, up to the age of about 18 or 19, is connected with the whole of the rest of my character (my weakness in study)."^[24]

[edit] Jewish background and Hitler

There is much debate about the extent to which Wittgenstein and his siblings saw themselves as Jews, and the issue has arisen in particular regarding Wittgenstein's schooldays, because Adolf Hitler was at the same school for part of the same time.^[27] Laurence Goldstein argues it is "overwhelmingly probable" the boys met each other: that Hitler, vicious and aggressive, would have hated and envied Wittgenstein, a "stammering, precocious, precious, aristocratic upstart ..."^[28] Other commentators have dismissed as irresponsible and uninformed any suggestion that Wittgenstein's wealth and unusual personality may have fed Hitler's antisemitism, in part because there is no indication that Hitler would have seen Wittgenstein as Jewish.^[29]

Adolf Hitler (top right) at the Realschule in Linz. There have been claims that the boy on the bottom left is Wittgenstein, though the photograph seems to have been taken before Wittgenstein's time.^[30]

Vienna was at that time one of the most antisemitic cities in Europe, and any hint of a Jewish heritage had the potential to weigh heavily on a family. Certainly the Wittgenstein children were aware of their ancestry. Paul had created a family tree showing their descent from the Chief Rabbi Samson Wertheimer (1678–1724), the banker Samuel Oppenheimer (1678–1724), and the composers Giacomo Meyerbeer (1791–1864) and Felix Mendelssohn (1809–1847). There was nevertheless a streak of antisemitism among them. Wittgenstein famously compared the Jewish people to a Beule (boil or tumour) on Austrian society.^[31] His grandfather, Hermann Christian Wittgenstein, himself a Jew, had refused to allow his children to marry other Jews, and Wittgenstein's father had said that "in matters of honour one does not consult a Jew." McGuinness argues that Wittgenstein saw himself as completely German^[27]—Ray Monk writes that when Wittgenstein and Paul wanted to join a gym in Vienna that was restricted to those of Aryan origin, Wittgenstein was willing to lie about his background, whereas Paul was not.^[26]

Wittgenstein and Hitler were born just six days apart, though Hitler had been held back a year, while Wittgenstein was moved forward by one, so they ended up two grades apart at the Realschule.^[32] Monk estimates they were both at the school during the 1904–1905 school year, but says there is no evidence they had anything to do with each other.^[33] Hitler referred in Mein Kampf to a Jewish boy at the school, but there were 17 Jews there at the time: "At the Realschule I knew one Jewish boy. We were all on our guard in our relations with him, but only because his reticence and certain actions of his warned us to be discreet. Beyond that my companions and myself formed no particular opinion in regard to him."^[34] Several commentators have argued that a school photograph of Hitler (see above right; Hitler is on the top right) may show Wittgenstein in the lower left corner,^[30] but Hamann says the photograph stems from 1900 or 1901, before Wittgenstein's time.^[35]

[edit] Loss of faith

Arthur Schopenhauer (1788–1860): Wittgenstein turned to his work when he realized he had lost his faith.

It was while he was at the Realschule that he decided he had lost his faith in God, or rather had had none to begin with, and that he could not believe any of the things a Christian was supposed to believe. He nevertheless clung to the importance of the idea of confession, something he engaged in several times throughout his life, where he confessed to friends and family that he had lied, or had said or done something that meant he had not been true to himself. He wrote in his diaries about having made a major confession to his oldest sister, Hermine, while he was at the Realschule; Monk writes that it may have been about his loss of faith. He also discussed it with Gretl, his other sister, who directed him to Arthur Schopenhauer's The World as Will and Representation. Schopenhauer's idealism is a version of Immanuel Kant's: that the world of the senses is mere appearance, and the ethical will the only reality, a view that Wittgenstein adopted until he abandoned it when he began to study Gottlob Frege and logic, just before he went to Cambridge, though Monk writes he returned to it in the Tractatus, where his views on idealism and realism collided.^[36]

[edit] Influence of Otto Weininger

Otto Weininger (1880–1903): Wittgenstein was greatly influenced by his suicide.

During Wittgenstein's first term at the Realschule, on 3 October 1903, the Viennese philosopher Otto Weininger rented the room in the house at Schwarzspanierstrasse 15, Vienna, that Beethoven had died in, and shot himself. His book Geschlecht und Charakter (Sex and Character) had been published to mostly terrible reviews a few months earlier, but it had received a great review from August Strindberg; that and his suicide turned Weininger into a cult figure, and someone Wittgenstein came to admire. Monk writes that Wittgenstein was ashamed that he had not also killed himself, seeing Weininger's suicide as an ethical deed in a rotten world—a world that Weininger saw composed of superficial anarchy and a materialist interpretation of history, where there are no great philosophers or artists, and where genius is a form of madness—and recommended to everyone that they read Weininger's book.^[37]

Weininger—who like Wittgenstein was gay and had Jewish roots—argued that the concepts male and female exist only as Platonic forms, and that the essence of woman is sexual. Whereas men are basically rational, women operate only at the level of their emotions and sexual organs; Jews are similar, saturated with femininity, with no sense of right and wrong, and no soul. Wittgenstein saw in this argument the answers to issues he had been struggling with. Weininger argues that man must choose between his masculine and feminine sides, consciousness and unconsciousness, Platonic love and sexuality. Love and sexual desire stand in contradiction, and the love between a woman and a man is therefore doomed to misery or immorality. The only life worth living is the spiritual one—to live as a woman or a Jew means one has no right to live at all; the choice is genius or death. Monk writes that Wittgenstein's thoughts of suicide, which receded to some extent only when Russell began to admire his work in 1912, suggest he had embraced Weininger's bleak outlook.^[37]

[edit] 1906–1913: University

[edit] Engineering at Berlin and Manchester

The old Technische Hochschule in Charlottenburg, Berlin.

He began his studies in mechanical engineering at the Technische Hochscule in Charlottenburg, Berlin, on 23 October 1906, lodging with the family of a professor there, Dr Jolles. He attended for three semesters, and was awarded a diploma on 5 May 1908, after developing an interest in aeronautics.^[38]

He arrived at the Victoria University of Manchester in the spring of 1908 to do his doctorate, full of plans for aeronautical projects, including designing and flying his own plane. He conducted research into the behavior of kites in the upper atmosphere, experimenting at a meteorological observation site near Glossop, and living nearby at the Grouse Inn, a pub on Chunal Road, Derbyshire, where he was one of only two guests, along with a Mr. Rimmer.^[39] He also worked on the design of a propeller with small jet engines on the end of its blades, something he patented in 1911 and which earned him a research studentship from the university in the autumn of 1908.^[40]

Witttgenstein stayed at the Grouse Inn in 1908 while he conducted research near Glossop, writing to Hermine that he loved the isolation, but was less enamored of the toilet facilities.^[39]

It was around this time that he became interested in the foundations of mathematics, particularly after reading Bertrand Russell's The Principles of Mathematics (1903), and Gottlob Frege's Grundgesetze der Arithmetik, vol. 1 (1893) and vol. 2 (1903).^[41] Wittgenstein's sister Hermine said he became obsessed with mathematics as a result, and was anyway losing interest in aeronautics. He decided instead that he needed to study philosophy, describing himself as in a "constant, indescribable, almost pathological state of agitation."^[40] In the summer of 1911 he decided to visit Frege at the University of Jena to show him some philosophy he had written, and to ask whether it was worth pursuing; the work did not survive, perhaps because, as he said, Frege wiped the floor with him.^[42] He wrote:

I was shown into Frege's study. Frege was a small, neat man with a pointed beard who bounced around the room as he talked. He absolutely wiped the floor with me, and I felt very depressed; but at the end he said "You must come again," so I cheered up. I had several discussions with him after that. Frege would never talk about anything but logic and mathematics, if I started on some other subject, he would say something polite and then plunge back into logic and mathematics.^[43]

[edit] Arrival at Cambridge

Wittgenstein wanted to study with Frege, but Frege suggested he attend the University of Cambridge to study under Russell, so on 18 October 1911 Wittgenstein arrived unannounced at Russell's rooms in Trinity College.^[44] Russell was having tea with C.K. Ogden, when:

... an unknown German appeared, speaking very little English but refusing to speak German. He turned out to be a man who had learned engineering at Charlottenburg, but during this course had acquired, by himself, a passion for the philosophy of mathematics & has now come to Cambridge on purpose to hear me.^[42]

Bertrand Russell in 1893.

He was soon not only attending Russell's lectures, but dominating them. The lectures were poorly attended and Russell often found himself lecturing only to C.D. Broad, E.H. Neville, and H.T.J. Norton, so he was quite pleased at first when Wittgenstein turned up, though less so as the weeks wore on.^[42] Wittgenstein started following him after lectures back to his rooms to discuss more philosophy, until it was time for the evening meal in Hall. Russell grew irritated; he wrote to his lover Lady Ottoline Morrell: "My German friend threatens to be an infliction."^[45]

Russell revised his opinion, and in fact came to be overpowered by Wittgenstein's forceful personality. He wrote in November 1911 that he had at first thought Wittgenstein might be a crank, but soon decided he was a genius: "Some of his early views made the decision difficult. He maintained, for example, at one time that all existential propositions are meaningless. This was in a lecture room, and I invited him to consider the proposition: 'There is no hippopotamus in this room at present.' When he refused to believe this, I looked under all the desks without finding one; but he remained unconvinced."^[45] Three months after Wittgenstein's arrival he told Morrell: "I love him & feel he will solve the problems I am too old to solve ... He is the young man one hopes for."^[46] The role-reversal between him and Wittgenstein was such that he wrote in 1916, after Wittgenstein had criticized his own work: "His criticism, 'tho I don't think he realized it at the time, was an event of first-rate importance in my life, and affected everything I have done since. I saw that he was right, and I saw that I could not hope ever again to do fundamental work in philosophy."^[47]

[edit] Moral Sciences Club and Apostles

In 1912 Wittgenstein joined the Cambridge Moral Sciences Club, an influential discussion group for philosophy dons and students, delivering his first paper there on 29 November that year, a four-minute talk defining philosophy as "all those primitive propositions which are assumed as true without proof by the various sciences."^[48] From that point on he dominated the society, to the point where special starred meetings had to be organized which dons were not to attend, though everyone knew the arrangement was directed only at Wittgenstein. He had to stop attending entirely in the 1930s after complaints that he gave no one else a chance to speak.^[49]

The club became legendary within philosophy because of a meeting on 25 October 1946 at Richard Braithwaite's rooms in King's, where Karl Popper, another Viennese philosopher, had been invited as the guest speaker. Popper's paper was "Are there philosophical problems?", in which he struck up a position against Wittgenstein's, contending that problems in philosophy are real, not just linguistic puzzles as Wittgenstein argued. Accounts vary as to what happened next, but Wittgenstein was apparently infuriated and started waving a hot poker at Popper, demanding that Popper give him an example of a moral rule. Popper offered one—"Not to threaten visiting speakers with pokers"—at which point Russell had to tell Wittgenstein to put the poker down and Wittgenstein stormed out. It was the only time the philosophers, three of the most eminent in the world, were ever in the same room together.^[50] The minutes record that the meeting was "charged to an unusual degree with a spirit of controversy."^[51]

John Maynard Keynes also invited him to join the Cambridge Apostles, an elite secret society formed in 1820, which both Russell and Moore had joined as students, but Wittgenstein did not enjoy it and attended infrequently. Russell had been worried that Wittgenstein, with his literal-mindedness, would not appreciate the group's humour or the fact that the members were in love with each other.^[52] Lytton Strachey wrote to Keynes on 17 May 1912 about an Apostles meeting where Wittgenstein was present, calling him Herr Sinckel-Winckel: "Oliver and Herr Sinckel-Winckel hard at it on universals and particulars. The latter oh! so bright—but quelle souffrance! Oh God! God! "If A loves B"—"There may be a common quality"—"Not analysable that way at all, but the complexes have certain qualities." How shall I manage to slink off to bed?"^[53]

[edit] Relationship with David Pinsent

It was Russell who introduced Wittgenstein to David Hume Pinsent (1891–1918) in the summer of 1912. A mathematics undergraduate and descendant of David Hume, Pinsent became what Wittgenstein called his first and only friend,^[54] and is widely regarded as the first of three or four men Wittgenstein fell in love with—followed by Francis Skinner in 1930, Ben Richards in the late 1940s, and to a lesser extent Keith Kirk in 1940—though Pinsent and Kirk did not respond in kind.^[55]

The men worked together on experiments in the psychology laboratory about the role of rhythm in the appreciation of music, and Wittgenstein delivered a paper about it to the British Psychological Association in Cambridge in 1912. They also travelled together, including to Iceland in September 1912—the expenses paid by Wittgenstein's father, including first-class travel, and new clothes and spending money for Pinsent—and later to Norway. Pinsent's diaries have provided researchers with a wealth of material about Wittgenstein's personality, and what comes across strongly is how sensitive and nervous he was, attuned to the tiniest slight or change in mood from Pinsent, with Pinsent regularly writing that Wittgenstein was in a huff about something.^[56] He wrote about shopping for furniture with Wittgenstein in Cambridge when the latter was given rooms in Trinity; most of what they found in the stores was not frugal enough for Wittgenstein's taste: "I went and helped him interview a lot of furniture at various shops ... It was rather amusing: he is terribly fastidious and we led the shopman a frightful dance, Vittgenstein [sic] ejaculating "No—Beastly!" to 90 percent of what he shewed us!"^[53]

He wrote in May 1912 that Wittgenstein had just begun to study philosophy: "[h]e expresses the most naive surprise that all the philosophers he once worshipped in ignorance are after all stupid and dishonest and make disgusting mistakes!"^[53] The last time they saw each other was at Birmingham train station on 8 October 1913, when they said goodbye before Wittgenstein left to live in Norway. Despite the physical distance that had grown between them because of the war—Pinsent's last letter to Wittgenstein was dated 14 September 1916—when Pinsent died in a plane crash in May 1918, Wittgenstein was distraught to the point of being suicidal, and three years later dedicated the Tractatus to him.^[53]

[edit] 1913–1920: World War I and the Tractatus

[Books By This Author

• Tractatus Logico-Philosophicus
• Tractatus Logico-Philosophicus