The ''Tractatus Logico-Philosophicus'' (widely abbreviated and
cited as TLP) is the only book-length philosophical work by the Austrian
philosopher
Philosophy ('love of wisdom' in Ancient Greek) is a systematic study of general and fundamental questions concerning topics like existence, reason, knowledge, Value (ethics and social sciences), value, mind, and language. It is a rational an ...
Ludwig Wittgenstein
Ludwig Josef Johann Wittgenstein ( ; ; 26 April 1889 – 29 April 1951) was an Austrian philosopher who worked primarily in logic, the philosophy of mathematics, the philosophy of mind, and the philosophy of language.
From 1929 to 1947, Witt ...
that was published during his lifetime. The project had a broad goal: to identify the relationship between language and reality, and to define the limits of science. Wittgenstein wrote the notes for the ''Tractatus'' while he was a soldier during
World War I
World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting to ...
and completed it during a military leave in the summer of 1918. It was originally published in German in 1921 as ''Logisch-Philosophische Abhandlung'' (Logical-Philosophical Treatise). In 1922 it was published together with an English translation and a Latin title, which was suggested by
G. E. Moore
George Edward Moore (4 November 1873 – 24 October 1958) was an English philosopher, who with Bertrand Russell, Ludwig Wittgenstein and earlier Gottlob Frege was among the initiators of analytic philosophy. He and Russell began de-emphasizing ...
as homage to
Baruch Spinoza's ''
Tractatus Theologico-Politicus'' (1670).
The ''Tractatus'' is written in an austere and succinct literary style, containing almost no arguments as such, but consists of 525 declarative statements altogether, which are hierarchically numbered.
The ''Tractatus'' is recognized by philosophers as one of the most significant philosophical works of the twentieth century and was influential chiefly amongst the
logical positivist philosophers of the
Vienna Circle, such as
Rudolf Carnap
Rudolf Carnap (; ; 18 May 1891 – 14 September 1970) was a German-language philosopher who was active in Europe before 1935 and in the United States thereafter. He was a major member of the Vienna Circle and an advocate of logical positivism.
...
and
Friedrich Waismann and
Bertrand Russell
Bertrand Arthur William Russell, 3rd Earl Russell, (18 May 1872 – 2 February 1970) was a British philosopher, logician, mathematician, and public intellectual. He had influence on mathematics, logic, set theory, and various areas of analytic ...
's article "The Philosophy of Logical Atomism".
Wittgenstein's later works, notably the posthumously published ''
Philosophical Investigations
''Philosophical Investigations'' () is a work by the philosopher Ludwig Wittgenstein, published posthumously in 1953.
''Philosophical Investigations'' is divided into two parts, consisting of what Wittgenstein calls, in the preface, ''Bemer ...
'', criticised many of his ideas in the ''Tractatus''. There is, however, a common thread in Wittgenstein's thinking, in spite of those criticisms of the ''Tractatus'' in later writings. Indeed, the contrast between 'early' and 'late' Wittgenstein has been countered by such scholars as Pears (1987) and Hilmy (1987). For example, a relevant, yet neglected aspect of continuity in Wittgenstein's thought concerns 'meaning' as 'use'. Connecting his early and later writings on 'meaning as use' is his appeal to direct consequences of a term or phrase, reflected, for example, in his speaking of language as a 'calculus'. These passages are crucial to Wittgenstein's view of 'meaning as use', though they have been widely neglected in scholarly literature. The centrality and importance of these passages are corroborated and augmented by renewed examination of Wittgenstein's ''
Nachlaß'', as is done in "From Tractatus to Later Writings and Back – New Implications from the ''Nachlass''" (de Queiroz 2023).
Description and context
The ''Tractatus'' employs an austere and succinct literary style. The work contains almost no arguments as such, but rather consists of declarative statements, or passages, that are meant to be self-evident. The statements are hierarchically numbered, with seven basic propositions at the primary level (numbered 1–7), with each sub-level being a comment on or elaboration of the statement at the next higher level (e.g., 1, 1.1, 1.11, 1.12, 1.13). In all, the Tractatus comprises 525 numbered statements.
When
Bertrand Russell
Bertrand Arthur William Russell, 3rd Earl Russell, (18 May 1872 – 2 February 1970) was a British philosopher, logician, mathematician, and public intellectual. He had influence on mathematics, logic, set theory, and various areas of analytic ...
suggested to Wittgenstein that he ought to provide arguments and not merely state what he thinks, Wittgenstein replied that this would spoil the book's beauty and would be like touching a flower with muddy hands.
The ''Tractatus'' is recognized by philosophers as a significant philosophical work of the twentieth century and was influential chiefly amongst the
logical positivist philosophers of the
Vienna Circle, such as
Rudolf Carnap
Rudolf Carnap (; ; 18 May 1891 – 14 September 1970) was a German-language philosopher who was active in Europe before 1935 and in the United States thereafter. He was a major member of the Vienna Circle and an advocate of logical positivism.
...
and
Friedrich Waismann. Bertrand Russell's article "The Philosophy of Logical Atomism" is presented as a working out of ideas that he had learned from Wittgenstein.
The English translation of the Tractatus was published with an introduction by Bertrand Russell. Wittgenstein was unimpressed by Russell's introduction, considering it superficial and a misunderstanding of his work.
Main theses

There are seven main
proposition
A proposition is a statement that can be either true or false. It is a central concept in the philosophy of language, semantics, logic, and related fields. Propositions are the object s denoted by declarative sentences; for example, "The sky ...
s in the text. These are:
# The world is everything that is the case.
# What is the case (a fact) is the existence of states of affairs.
# A logical picture of facts is a thought.
# A thought is a proposition with a sense.
# A proposition is a truth-function of elementary propositions. (An elementary proposition is a truth-function of itself.)
# The general form of a proposition is the general form of a
truth function, which is: