It has been said that Anglo-American philosophy of the 20th century is a series of footnotes to the writings of Ludwig Wittgenstein. Who was Ludwig Wittgenstein?
He was born in 1889 to parents of Jewish descent; his mother was a Roman Catholic, his father Protestant. He was educated at home, a prosperous one where Brahms was a frequent visitor. He studied engineering and, in 1908, was absorbed by the mathematical problems of designing a jet reaction propeller. This was in England, where, after meeting Bertrand Russell, G. E. Moore, Whitehead, and Keynes, he turned to philosophy - the philosophy of mathematics.
When his father died in 1912, he gave away his inheritance. In World War I he fought on the eastern front for the Austrian Army; when he was captured by the Italians in 1918, he had a completed draft of his first great philosophical work in his rucksack. This was his ''Tractatus Logico-Philosophicus,'' a key work in the school of logical positivism. He had a devil of a time getting it published.
Thinking he had solved the major philosophical problems of his time, Wittgenstein became a schoolmaster in Germany after the war. In 1926, he designed and built a house for his sister. In 1929 he got his PhD at Cambridge. From 1930 until 1947, when he quit in disgust over the profession of professor, he was a fellow of Trinity College. There he conducted his lectures - without notes - in his rooms. A student recalls, ''He thought before the class.'' The lectures were published in the form of notebooks and his ''Investigations.'' Throughout his career as a teacher of philosophy he suffered periods of aridity, not unlike those that trouble artists. He spent his last years living for periods of months at a time in extreme isolation.
Finally, von Wright notes, Ludwig Wittgenstein was an expert whistler, known to perform whole symphonic movements by heart.
G. H. von Wright has written, ''His life was a constant journey, and doubt was the moving force within him. He never looked back on his earlier positions, and when he did so it was usually to repudiate them.''
Complicated, then, as the man was, it comes as a surprise to learn that in the beautiful collection of general remarks published under the title ''Culture and Value,'' Wittgenstein appears as a master of lucidity, simplicity, and concreteness. While his philosophical works are difficult to understand, even for his students and admirers (and not a few enemies), these passages culled from the manuscript material left unpublished at his death have a classic polish. They make this enigmatic and troubled man seem approachable, knowable, and charming. This fierce enemy of pretense wrote: ''Everything ritualistic ... must be strictly avoided, because it immediately turns rotten.
''Of course a kiss is a ritual too and it isn't rotten, but ritual is permissible only to the extent that it is as genuine as a kiss.''
That gaiety is followed directly by solemnity: ''It is a great temptation to try to make the spirit explicit.''
The lectures he gave in his Cambridge rooms were scenes of great tension, severe thought, and personal harshness - but of grace as well. Von Wright wrote that the memoirs written by students (such as Malcolm), while indispensable, fail to capture the beauty of Wittgenstein's conversation. Readers of ''Culture and Value'' who linger over its precious pages will come to know that beauty. The voice is, after a while, unmistakable.
''Genius is talent in which character makes itself heard,'' wrote the philosopher, whose initial pride (remember, he considered his first work to be final) gradually yields to something far more spiritual. As he wrote in 1937, ''The ediface of your pride has to be dismantled. And that is terribly hard work.''
It is, I think, as a writer that Wittgenstein will be most treasured. Out of his immense self-knowledge, in 1948, a year after quitting Cambridge, he wrote: ''When he was old Charlemagne tried to learn to write, but without success: and similarly someone may fail when he tries to acquire a manner of thinking. He never becomes fluent in it.'' It is said that, although sometimes in great pain in his last years, he was not unhappy. In 1950 he wrote, ''Life can educate one to a belief in God.'' Toward the very end there was a burst of creativity.