Ludwig Josef Johann Wittgenstein (26 April 1889 – 29 April
1951) was an Austrian-British philosopher who worked
primarily in the areas of logic, philosophy of mathematics, philosophy of mind, and philosophy of language.
Described by his mentor and colleague Bertrand Russell as "the most perfect example I have ever
known of genius as traditionally conceived, passionate, profound,
intense, and dominating,"
Wittgenstein is considered by many to be the greatest philosopher of
the 20th century.
Instrumental in inspiring two of the century's principal philosophical
movements, logical positivism and ordinary language philosophy,
he is considered one of the most important figures in analytic philosophy. According to an end of the century
poll, professional philosophers rank both his Tractatus Logico-Philosophicus
(1921) and Philosophical Investigations
(1953) among the top five most important books in twentieth-century
philosophy, the latter standing out as "the one crossover masterpiece in
twentieth-century philosophy, appealing across diverse specializations
and philosophical orientations."
Wittgenstein's influence has been felt in nearly every field of the humanities
and social sciences, yet there are widely
diverging interpretations of his thought.
Wittgenstein's thought is usually divided between his "early" period,
exemplified by the Tractatus, the only philosophy book he
published in his lifetime, and his "later" period, best articulated in
the Investigations. The early Wittgenstein was concerned with the
relationship between propositions and the world, and saw the aim of
philosophy as an attempt to describe that relationship and correct
misconceptions about language. The later Wittgenstein was stridently
anti-systematic in his approach and emphasized philosophy as a kind of
"therapy," and rejected many of the conclusions of the Tractatus.
The later Wittgenstein provided a detailed account of the many possible
uses of ordinary language, calling language a
series of interchangeable "language
games" in which the meanings of words are derived not from any
inherent logical structure, but from their public usage (the so-called
"meaning is use" argument); thus there can be no private language.